Merge branch 'next' of https://github.com/gnss-sdr/gnss-sdr into next

README.md

@@ -578,7 +578,7 @@ $ sudo port install doxygen +docs
 You also might need to activate a Python installation. The list of installed versions can be retrieved with:
 
 ~~~~~~
-$ port select list python
+$ port select --list python
 ~~~~~~
 
 and you can activate a certain version by typing:

cmake/Modules/SetupPython.cmake

@@ -100,6 +100,13 @@ else()
             gnsssdr_python_check_module("mako >= ${GNSSSDR_MAKO_MIN_VERSION}" mako "mako.__version__ >= '${GNSSSDR_MAKO_MIN_VERSION}'" MAKO_FOUND)
             gnsssdr_python_check_module("six - python 2 and 3 compatibility library" six "True" SIX_FOUND)
         endif()
+        if(NOT MAKO_FOUND OR NOT SIX_FOUND)
+            unset(PYTHON_EXECUTABLE)
+            find_package(PythonInterp ${GNSSSDR_PYTHON_MIN_VERSION})
+            gnsssdr_python_check_module("python >= ${GNSSSDR_PYTHON_MIN_VERSION}" sys "sys.version.split()[0] >= '${GNSSSDR_PYTHON_MIN_VERSION}'" PYTHON_MIN_VER_FOUND)
+            gnsssdr_python_check_module("mako >= ${GNSSSDR_MAKO_MIN_VERSION}" mako "mako.__version__ >= '${GNSSSDR_MAKO_MIN_VERSION}'" MAKO_FOUND)
+            gnsssdr_python_check_module("six - python 2 and 3 compatibility library" six "True" SIX_FOUND)
+        endif()
     endif()
 endif()
 

src/algorithms/acquisition/adapters/beidou_b1i_pcps_acquisition.cc

@@ -123,7 +123,7 @@ BeidouB1iPcpsAcquisition::BeidouB1iPcpsAcquisition(
     threshold_ = 0.0;
     doppler_step_ = 0;
     gnss_synchro_ = nullptr;
-    channel_fsm_ = nullptr;
+    
     if (in_streams_ > 1)
         {
             LOG(ERROR) << "This implementation only supports one input stream";

src/algorithms/acquisition/adapters/beidou_b1i_pcps_acquisition.h

@@ -102,7 +102,7 @@ public:
     /*!
       * \brief Set channel fsm associated to this acquisition instance
       */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm) override
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm) override
     {
         channel_fsm_ = channel_fsm;
         acquisition_->set_channel_fsm(channel_fsm);
@@ -173,7 +173,7 @@ private:
     bool bit_transition_flag_;
     bool use_CFAR_algorithm_flag_;
     uint32_t channel_;
-    std::shared_ptr<ChannelFsm> channel_fsm_;
+    std::weak_ptr<ChannelFsm> channel_fsm_;
     float threshold_;
     uint32_t doppler_max_;
     uint32_t doppler_step_;

src/algorithms/acquisition/adapters/beidou_b3i_pcps_acquisition.cc

@@ -121,7 +121,7 @@ BeidouB3iPcpsAcquisition::BeidouB3iPcpsAcquisition(
     threshold_ = 0.0;
     doppler_step_ = 0;
     gnss_synchro_ = nullptr;
-    channel_fsm_ = nullptr;
+    
     if (in_streams_ > 1)
         {
             LOG(ERROR) << "This implementation only supports one input stream";

src/algorithms/acquisition/adapters/beidou_b3i_pcps_acquisition.h

@@ -101,7 +101,7 @@ public:
     /*!
       * \brief Set channel fsm associated to this acquisition instance
       */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm) override
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm) override
     {
         channel_fsm_ = channel_fsm;
         acquisition_->set_channel_fsm(channel_fsm);
@@ -172,7 +172,7 @@ private:
     bool bit_transition_flag_;
     bool use_CFAR_algorithm_flag_;
     unsigned int channel_;
-    std::shared_ptr<ChannelFsm> channel_fsm_;
+    std::weak_ptr<ChannelFsm> channel_fsm_;
     float threshold_;
     unsigned int doppler_max_;
     unsigned int doppler_step_;

src/algorithms/acquisition/adapters/galileo_e1_pcps_8ms_ambiguous_acquisition.cc

@@ -110,7 +110,7 @@ GalileoE1Pcps8msAmbiguousAcquisition::GalileoE1Pcps8msAmbiguousAcquisition(
     threshold_ = 0.0;
     doppler_step_ = 0;
     gnss_synchro_ = nullptr;
-    channel_fsm_ = nullptr;
+    
     if (in_streams_ > 1)
         {
             LOG(ERROR) << "This implementation only supports one input stream";

src/algorithms/acquisition/adapters/galileo_e1_pcps_8ms_ambiguous_acquisition.h

@@ -96,7 +96,7 @@ public:
     /*!
       * \brief Set channel fsm associated to this acquisition instance
       */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm) override
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm) override
     {
         channel_fsm_ = channel_fsm;
         acquisition_cc_->set_channel_fsm(channel_fsm);
@@ -156,7 +156,7 @@ private:
     unsigned int vector_length_;
     unsigned int code_length_;
     unsigned int channel_;
-    std::shared_ptr<ChannelFsm> channel_fsm_;
+    std::weak_ptr<ChannelFsm> channel_fsm_;
     float threshold_;
     unsigned int doppler_max_;
     unsigned int doppler_step_;

src/algorithms/acquisition/adapters/galileo_e1_pcps_ambiguous_acquisition.cc

@@ -154,7 +154,7 @@ GalileoE1PcpsAmbiguousAcquisition::GalileoE1PcpsAmbiguousAcquisition(
     threshold_ = 0.0;
     doppler_step_ = 0;
     gnss_synchro_ = nullptr;
-    channel_fsm_ = nullptr;
+    
     if (in_streams_ > 1)
         {
             LOG(ERROR) << "This implementation only supports one input stream";

src/algorithms/acquisition/adapters/galileo_e1_pcps_ambiguous_acquisition.h

@@ -100,7 +100,7 @@ public:
     /*!
       * \brief Set channel fsm associated to this acquisition instance
       */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm) override
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm) override
     {
         channel_fsm_ = channel_fsm;
         acquisition_->set_channel_fsm(channel_fsm);
@@ -171,7 +171,7 @@ private:
     bool use_CFAR_algorithm_flag_;
     bool acquire_pilot_;
     unsigned int channel_;
-    std::shared_ptr<ChannelFsm> channel_fsm_;
+    std::weak_ptr<ChannelFsm> channel_fsm_;
     float threshold_;
     unsigned int doppler_max_;
     unsigned int doppler_step_;

src/algorithms/acquisition/adapters/galileo_e1_pcps_ambiguous_acquisition_fpga.cc

@@ -44,6 +44,13 @@
 #include <complex>  // for complex
 #include <cstring>  // for memcpy
 
+// the following flags are FPGA-specific and they are using arrange the values of the fft of the local code in the way the FPGA
+// expects. This arrangement is done in the initialisation to avoid consuming unnecessary clock cycles during tracking.
+#define QUANT_BITS_LOCAL_CODE 16
+#define SELECT_LSBits 0x0000FFFF         // Select the 10 LSbits out of a 20-bit word
+#define SELECT_MSBbits 0xFFFF0000        // Select the 10 MSbits out of a 20-bit word
+#define SELECT_ALL_CODE_BITS 0xFFFFFFFF  // Select a 20 bit word
+#define SHL_CODE_BITS 65536              // shift left by 10 bits
 
 GalileoE1PcpsAmbiguousAcquisitionFpga::GalileoE1PcpsAmbiguousAcquisitionFpga(
     ConfigurationInterface* configuration,
@@ -67,7 +74,7 @@ GalileoE1PcpsAmbiguousAcquisitionFpga::GalileoE1PcpsAmbiguousAcquisitionFpga(
     acq_parameters.repeat_satellite = configuration_->property(role + ".repeat_satellite", false);
     DLOG(INFO) << role << " satellite repeat = " << acq_parameters.repeat_satellite;
 
-    float downsampling_factor = configuration_->property(role + ".downsampling_factor", 4.0);
+    uint32_t downsampling_factor = configuration_->property(role + ".downsampling_factor", 4);
     acq_parameters.downsampling_factor = downsampling_factor;
 
     fs_in = fs_in / downsampling_factor;
@@ -97,15 +104,16 @@ GalileoE1PcpsAmbiguousAcquisitionFpga::GalileoE1PcpsAmbiguousAcquisitionFpga(
     acq_parameters.device_name = device_name;
     acq_parameters.samples_per_ms = nsamples_total / sampled_ms;
     acq_parameters.samples_per_code = nsamples_total;
-    acq_parameters.excludelimit = static_cast<uint32_t>(std::round(static_cast<double>(fs_in) / GALILEO_E1_CODE_CHIP_RATE_HZ));
+    acq_parameters.excludelimit = static_cast<unsigned int>(1 + ceil((1.0 / GALILEO_E1_CODE_CHIP_RATE_HZ) * static_cast<float>(fs_in)));
 
     // compute all the GALILEO E1 PRN Codes (this is done only once in the class constructor in order to avoid re-computing the PRN codes every time
     // a channel is assigned)
     auto* fft_if = new gr::fft::fft_complex(nsamples_total, true);  // Direct FFT
     auto* code = new std::complex<float>[nsamples_total];           // buffer for the local code
     auto* fft_codes_padded = static_cast<gr_complex*>(volk_gnsssdr_malloc(nsamples_total * sizeof(gr_complex), volk_gnsssdr_get_alignment()));
-    d_all_fft_codes_ = new lv_16sc_t[nsamples_total * GALILEO_E1_NUMBER_OF_CODES];  // memory containing all the possible fft codes for PRN 0 to 32
+    d_all_fft_codes_ = new uint32_t[(nsamples_total * GALILEO_E1_NUMBER_OF_CODES)];  // memory containing all the possible fft codes for PRN 0 to 32
-    float max;                                                                      // temporary maxima search
+    float max;                                                                       // temporary maxima search
+    int32_t tmp, tmp2, local_code, fft_data;
 
     for (uint32_t PRN = 1; PRN <= GALILEO_E1_NUMBER_OF_CODES; PRN++)
         {
@@ -153,24 +161,33 @@ GalileoE1PcpsAmbiguousAcquisitionFpga::GalileoE1PcpsAmbiguousAcquisitionFpga(
                             max = std::abs(fft_codes_padded[i].imag());
                         }
                 }
-            for (uint32_t i = 0; i < nsamples_total; i++)  // map the FFT to the dynamic range of the fixed point values an copy to buffer containing all FFTs
+            // map the FFT to the dynamic range of the fixed point values an copy to buffer containing all FFTs
+            // and package codes in a format that is ready to be written to the FPGA
+            for (uint32_t i = 0; i < nsamples_total; i++)
                 {
-                    d_all_fft_codes_[i + nsamples_total * (PRN - 1)] = lv_16sc_t(static_cast<int32_t>(floor(fft_codes_padded[i].real() * (pow(2, 9) - 1) / max)),
+                    tmp = static_cast<int32_t>(floor(fft_codes_padded[i].real() * (pow(2, QUANT_BITS_LOCAL_CODE - 1) - 1) / max));
-                        static_cast<int32_t>(floor(fft_codes_padded[i].imag() * (pow(2, 9) - 1) / max)));
+                    tmp2 = static_cast<int32_t>(floor(fft_codes_padded[i].imag() * (pow(2, QUANT_BITS_LOCAL_CODE - 1) - 1) / max));
+                    local_code = (tmp & SELECT_LSBits) | ((tmp2 * SHL_CODE_BITS) & SELECT_MSBbits);  // put together the real part and the imaginary part
+                    fft_data = local_code & SELECT_ALL_CODE_BITS;
+                    d_all_fft_codes_[i + (nsamples_total * (PRN - 1))] = fft_data;
                 }
         }
 
     acq_parameters.all_fft_codes = d_all_fft_codes_;
 
+    acq_parameters.num_doppler_bins_step2 = configuration_->property(role + ".second_nbins", 4);
+    acq_parameters.doppler_step2 = configuration_->property(role + ".second_doppler_step", 125.0);
+    acq_parameters.make_2_steps = configuration_->property(role + ".make_two_steps", false);
+    acq_parameters.max_num_acqs = configuration_->property(role + ".max_num_acqs", 2);
     // reference for the FPGA FFT-IFFT attenuation factor
-    acq_parameters.total_block_exp = configuration_->property(role + ".total_block_exp", 14);
+    acq_parameters.total_block_exp = configuration_->property(role + ".total_block_exp", 13);
 
     acquisition_fpga_ = pcps_make_acquisition_fpga(acq_parameters);
 
     channel_ = 0;
     doppler_step_ = 0;
     gnss_synchro_ = nullptr;
-    channel_fsm_ = nullptr;
+
     // temporary buffers that we can delete
     delete[] code;
     delete fft_if;

src/algorithms/acquisition/adapters/galileo_e1_pcps_ambiguous_acquisition_fpga.h

@@ -99,7 +99,7 @@ public:
     /*!
       * \brief Set channel fsm associated to this acquisition instance
       */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm) override
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm) override
     {
         channel_fsm_ = channel_fsm;
         acquisition_fpga_->set_channel_fsm(channel_fsm);
@@ -157,7 +157,7 @@ private:
     pcps_acquisition_fpga_sptr acquisition_fpga_;
     bool acquire_pilot_;
     uint32_t channel_;
-    std::shared_ptr<ChannelFsm> channel_fsm_;
+    std::weak_ptr<ChannelFsm> channel_fsm_;
     uint32_t doppler_max_;
     uint32_t doppler_step_;
     std::string dump_filename_;
@@ -166,7 +166,7 @@ private:
     unsigned int in_streams_;
     unsigned int out_streams_;
 
-    lv_16sc_t* d_all_fft_codes_;  // memory that contains all the code ffts
+    uint32_t* d_all_fft_codes_;  // memory that contains all the code ffts
 };
 
 #endif /* GNSS_SDR_GALILEO_E1_PCPS_AMBIGUOUS_ACQUISITION_FPGA_H_ */

src/algorithms/acquisition/adapters/galileo_e1_pcps_cccwsr_ambiguous_acquisition.cc

@@ -111,7 +111,7 @@ GalileoE1PcpsCccwsrAmbiguousAcquisition::GalileoE1PcpsCccwsrAmbiguousAcquisition
     threshold_ = 0.0;
     doppler_step_ = 0;
     gnss_synchro_ = nullptr;
-    channel_fsm_ = nullptr;
+    
     if (in_streams_ > 1)
         {
             LOG(ERROR) << "This implementation only supports one input stream";

src/algorithms/acquisition/adapters/galileo_e1_pcps_cccwsr_ambiguous_acquisition.h

@@ -96,7 +96,7 @@ public:
     /*!
       * \brief Set channel fsm associated to this acquisition instance
       */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm) override
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm) override
     {
         channel_fsm_ = channel_fsm;
         acquisition_cc_->set_channel_fsm(channel_fsm);
@@ -155,7 +155,7 @@ private:
     unsigned int code_length_;
     //unsigned int satellite_;
     unsigned int channel_;
-    std::shared_ptr<ChannelFsm> channel_fsm_;
+    std::weak_ptr<ChannelFsm> channel_fsm_;
     float threshold_;
     unsigned int doppler_max_;
     unsigned int doppler_step_;

src/algorithms/acquisition/adapters/galileo_e1_pcps_quicksync_ambiguous_acquisition.cc

@@ -144,7 +144,7 @@ GalileoE1PcpsQuickSyncAmbiguousAcquisition::GalileoE1PcpsQuickSyncAmbiguousAcqui
     threshold_ = 0.0;
     doppler_step_ = 0;
     gnss_synchro_ = nullptr;
-    channel_fsm_ = nullptr;
+    
     if (in_streams_ > 1)
         {
             LOG(ERROR) << "This implementation only supports one input stream";

src/algorithms/acquisition/adapters/galileo_e1_pcps_quicksync_ambiguous_acquisition.h

@@ -97,7 +97,7 @@ public:
     /*!
       * \brief Set channel fsm associated to this acquisition instance
       */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm) override
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm) override
     {
         channel_fsm_ = channel_fsm;
         acquisition_cc_->set_channel_fsm(channel_fsm);
@@ -159,7 +159,7 @@ private:
     unsigned int code_length_;
     bool bit_transition_flag_;
     unsigned int channel_;
-    std::shared_ptr<ChannelFsm> channel_fsm_;
+    std::weak_ptr<ChannelFsm> channel_fsm_;
     float threshold_;
     unsigned int doppler_max_;
     unsigned int doppler_step_;

src/algorithms/acquisition/adapters/galileo_e1_pcps_tong_ambiguous_acquisition.cc

@@ -114,7 +114,7 @@ GalileoE1PcpsTongAmbiguousAcquisition::GalileoE1PcpsTongAmbiguousAcquisition(
     threshold_ = 0.0;
     doppler_step_ = 0;
     gnss_synchro_ = nullptr;
-    channel_fsm_ = nullptr;
+    
     if (in_streams_ > 1)
         {
             LOG(ERROR) << "This implementation only supports one input stream";

src/algorithms/acquisition/adapters/galileo_e1_pcps_tong_ambiguous_acquisition.h

@@ -96,7 +96,7 @@ public:
     /*!
       * \brief Set channel fsm associated to this acquisition instance
       */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm) override
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm) override
     {
         channel_fsm_ = channel_fsm;
         acquisition_cc_->set_channel_fsm(channel_fsm);
@@ -157,7 +157,7 @@ private:
     unsigned int vector_length_;
     unsigned int code_length_;
     unsigned int channel_;
-    std::shared_ptr<ChannelFsm> channel_fsm_;
+    std::weak_ptr<ChannelFsm> channel_fsm_;
     float threshold_;
     unsigned int doppler_max_;
     unsigned int doppler_step_;

src/algorithms/acquisition/adapters/galileo_e5a_noncoherent_iq_acquisition_caf.cc

@@ -119,7 +119,7 @@ GalileoE5aNoncoherentIQAcquisitionCaf::GalileoE5aNoncoherentIQAcquisitionCaf(
     threshold_ = 0.0;
     doppler_step_ = 0;
     gnss_synchro_ = nullptr;
-    channel_fsm_ = nullptr;
+    
     if (in_streams_ > 1)
         {
             LOG(ERROR) << "This implementation only supports one input stream";

src/algorithms/acquisition/adapters/galileo_e5a_noncoherent_iq_acquisition_caf.h

@@ -97,7 +97,7 @@ public:
     /*!
       * \brief Set channel fsm associated to this acquisition instance
       */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm) override
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm) override
     {
         channel_fsm_ = channel_fsm;
         acquisition_cc_->set_channel_fsm(channel_fsm);
@@ -160,7 +160,7 @@ private:
     unsigned int code_length_;
     bool bit_transition_flag_;
     unsigned int channel_;
-    std::shared_ptr<ChannelFsm> channel_fsm_;
+    std::weak_ptr<ChannelFsm> channel_fsm_;
     float threshold_;
     unsigned int doppler_max_;
     unsigned int doppler_step_;

src/algorithms/acquisition/adapters/galileo_e5a_pcps_acquisition.cc

@@ -152,7 +152,7 @@ GalileoE5aPcpsAcquisition::GalileoE5aPcpsAcquisition(ConfigurationInterface* con
     threshold_ = 0.0;
     doppler_step_ = 0;
     gnss_synchro_ = nullptr;
-    channel_fsm_ = nullptr;
+    
     if (in_streams_ > 1)
         {
             LOG(ERROR) << "This implementation only supports one input stream";

src/algorithms/acquisition/adapters/galileo_e5a_pcps_acquisition.h

@@ -88,7 +88,7 @@ public:
     /*!
       * \brief Set channel fsm associated to this acquisition instance
       */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm) override
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm) override
     {
         channel_fsm_ = channel_fsm;
         acquisition_->set_channel_fsm(channel_fsm);
@@ -169,7 +169,7 @@ private:
     unsigned int vector_length_;
     unsigned int code_length_;
     unsigned int channel_;
-    std::shared_ptr<ChannelFsm> channel_fsm_;
+    std::weak_ptr<ChannelFsm> channel_fsm_;
     unsigned int doppler_max_;
     unsigned int doppler_step_;
     unsigned int sampled_ms_;

src/algorithms/acquisition/adapters/galileo_e5a_pcps_acquisition_fpga.cc

@@ -44,6 +44,13 @@
 #include <complex>  // for complex
 #include <cstring>  // for strcpy, memcpy
 
+// the following flags are FPGA-specific and they are using arrange the values of the fft of the local code in the way the FPGA
+// expects. This arrangement is done in the initialisation to avoid consuming unnecessary clock cycles during tracking.
+#define QUANT_BITS_LOCAL_CODE 16
+#define SELECT_LSBits 0x0000FFFF         // Select the 10 LSbits out of a 20-bit word
+#define SELECT_MSBbits 0xFFFF0000        // Select the 10 MSbits out of a 20-bit word
+#define SELECT_ALL_CODE_BITS 0xFFFFFFFF  // Select a 20 bit word
+#define SHL_CODE_BITS 65536              // shift left by 10 bits
 
 GalileoE5aPcpsAcquisitionFpga::GalileoE5aPcpsAcquisitionFpga(ConfigurationInterface* configuration,
     const std::string& role,
@@ -64,7 +71,7 @@ GalileoE5aPcpsAcquisitionFpga::GalileoE5aPcpsAcquisitionFpga(ConfigurationInterf
     acq_parameters.repeat_satellite = configuration_->property(role + ".repeat_satellite", false);
     DLOG(INFO) << role << " satellite repeat = " << acq_parameters.repeat_satellite;
 
-    float downsampling_factor = configuration_->property(role + ".downsampling_factor", 1.0);
+    uint32_t downsampling_factor = configuration_->property(role + ".downsampling_factor", 1);
     acq_parameters.downsampling_factor = downsampling_factor;
     fs_in = fs_in / downsampling_factor;
 
@@ -98,15 +105,17 @@ GalileoE5aPcpsAcquisitionFpga::GalileoE5aPcpsAcquisitionFpga(ConfigurationInterf
     acq_parameters.samples_per_ms = nsamples_total / sampled_ms;
     acq_parameters.samples_per_code = nsamples_total;
 
-    acq_parameters.excludelimit = static_cast<uint32_t>(ceil((1.0 / GALILEO_E5A_CODE_CHIP_RATE_HZ) * static_cast<float>(acq_parameters.fs_in)));
+    acq_parameters.excludelimit = static_cast<unsigned int>(1 + ceil((1.0 / GALILEO_E5A_CODE_CHIP_RATE_HZ) * static_cast<float>(fs_in)));
 
     // compute all the GALILEO E5 PRN Codes (this is done only once in the class constructor in order to avoid re-computing the PRN codes every time
     // a channel is assigned)
     auto* fft_if = new gr::fft::fft_complex(nsamples_total, true);  // Direct FFT
     auto* code = new std::complex<float>[nsamples_total];           // buffer for the local code
     auto* fft_codes_padded = static_cast<gr_complex*>(volk_gnsssdr_malloc(nsamples_total * sizeof(gr_complex), volk_gnsssdr_get_alignment()));
-    d_all_fft_codes_ = new lv_16sc_t[nsamples_total * GALILEO_E5A_NUMBER_OF_CODES];  // memory containing all the possible fft codes for PRN 0 to 32
+    d_all_fft_codes_ = new uint32_t[(nsamples_total * GALILEO_E5A_NUMBER_OF_CODES)];  // memory containing all the possible fft codes for PRN 0 to 32
-    float max;                                                                       // temporary maxima search
+
+    float max;  // temporary maxima search
+    int32_t tmp, tmp2, local_code, fft_data;
 
     for (uint32_t PRN = 1; PRN <= GALILEO_E5A_NUMBER_OF_CODES; PRN++)
         {
@@ -154,24 +163,33 @@ GalileoE5aPcpsAcquisitionFpga::GalileoE5aPcpsAcquisitionFpga(ConfigurationInterf
                             max = std::abs(fft_codes_padded[i].imag());
                         }
                 }
-            for (uint32_t i = 0; i < nsamples_total; i++)  // map the FFT to the dynamic range of the fixed point values an copy to buffer containing all FFTs
+            // map the FFT to the dynamic range of the fixed point values an copy to buffer containing all FFTs
+            // and package codes in a format that is ready to be written to the FPGA
+            for (uint32_t i = 0; i < nsamples_total; i++)
                 {
-                    d_all_fft_codes_[i + nsamples_total * (PRN - 1)] = lv_16sc_t(static_cast<int32_t>(floor(fft_codes_padded[i].real() * (pow(2, 9) - 1) / max)),
+                    tmp = static_cast<int32_t>(floor(fft_codes_padded[i].real() * (pow(2, QUANT_BITS_LOCAL_CODE - 1) - 1) / max));
-                        static_cast<int32_t>(floor(fft_codes_padded[i].imag() * (pow(2, 9) - 1) / max)));
+                    tmp2 = static_cast<int32_t>(floor(fft_codes_padded[i].imag() * (pow(2, QUANT_BITS_LOCAL_CODE - 1) - 1) / max));
+                    local_code = (tmp & SELECT_LSBits) | ((tmp2 * SHL_CODE_BITS) & SELECT_MSBbits);  // put together the real part and the imaginary part
+                    fft_data = local_code & SELECT_ALL_CODE_BITS;
+                    d_all_fft_codes_[i + (nsamples_total * (PRN - 1))] = fft_data;
                 }
         }
 
     acq_parameters.all_fft_codes = d_all_fft_codes_;
 
     // reference for the FPGA FFT-IFFT attenuation factor
-    acq_parameters.total_block_exp = configuration_->property(role + ".total_block_exp", 14);
+    acq_parameters.total_block_exp = configuration_->property(role + ".total_block_exp", 13);
 
+    acq_parameters.num_doppler_bins_step2 = configuration_->property(role + ".second_nbins", 4);
+    acq_parameters.doppler_step2 = configuration_->property(role + ".second_doppler_step", 125.0);
+    acq_parameters.make_2_steps = configuration_->property(role + ".make_two_steps", false);
+    acq_parameters.max_num_acqs = configuration_->property(role + ".max_num_acqs", 2);
     acquisition_fpga_ = pcps_make_acquisition_fpga(acq_parameters);
 
     channel_ = 0;
     doppler_step_ = 0;
     gnss_synchro_ = nullptr;
-    channel_fsm_ = nullptr;
+
     // temporary buffers that we can delete
     delete[] code;
     delete fft_if;

src/algorithms/acquisition/adapters/galileo_e5a_pcps_acquisition_fpga.h

@@ -101,7 +101,7 @@ public:
     /*!
       * \brief Set channel fsm associated to this acquisition instance
       */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm) override
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm) override
     {
         channel_fsm_ = channel_fsm;
         acquisition_fpga_->set_channel_fsm(channel_fsm);
@@ -176,7 +176,7 @@ private:
     bool acq_iq_;
 
     uint32_t channel_;
-    std::shared_ptr<ChannelFsm> channel_fsm_;
+    std::weak_ptr<ChannelFsm> channel_fsm_;
     uint32_t doppler_max_;
     uint32_t doppler_step_;
     unsigned int in_streams_;
@@ -184,7 +184,7 @@ private:
 
     Gnss_Synchro* gnss_synchro_;
 
-    lv_16sc_t* d_all_fft_codes_;  // memory that contains all the code ffts
+    uint32_t* d_all_fft_codes_;  // memory that contains all the code ffts
 };
 
 #endif /* GNSS_SDR_GALILEO_E5A_PCPS_ACQUISITION_FPGA_H_ */

src/algorithms/acquisition/adapters/glonass_l1_ca_pcps_acquisition.cc

@@ -125,7 +125,7 @@ GlonassL1CaPcpsAcquisition::GlonassL1CaPcpsAcquisition(
     threshold_ = 0.0;
     doppler_step_ = 0;
     gnss_synchro_ = nullptr;
-    channel_fsm_ = nullptr;
+    
     if (in_streams_ > 1)
         {
             LOG(ERROR) << "This implementation only supports one input stream";

src/algorithms/acquisition/adapters/glonass_l1_ca_pcps_acquisition.h

@@ -98,7 +98,7 @@ public:
     /*!
       * \brief Set channel fsm associated to this acquisition instance
       */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm) override
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm) override
     {
         channel_fsm_ = channel_fsm;
         acquisition_->set_channel_fsm(channel_fsm);
@@ -162,7 +162,7 @@ private:
     bool bit_transition_flag_;
     bool use_CFAR_algorithm_flag_;
     unsigned int channel_;
-    std::shared_ptr<ChannelFsm> channel_fsm_;
+    std::weak_ptr<ChannelFsm> channel_fsm_;
     float threshold_;
     unsigned int doppler_max_;
     unsigned int doppler_step_;

src/algorithms/acquisition/adapters/glonass_l2_ca_pcps_acquisition.cc

@@ -124,7 +124,7 @@ GlonassL2CaPcpsAcquisition::GlonassL2CaPcpsAcquisition(
     threshold_ = 0.0;
     doppler_step_ = 0;
     gnss_synchro_ = nullptr;
-    channel_fsm_ = nullptr;
+    
     if (in_streams_ > 1)
         {
             LOG(ERROR) << "This implementation only supports one input stream";

src/algorithms/acquisition/adapters/glonass_l2_ca_pcps_acquisition.h

@@ -98,7 +98,7 @@ public:
     /*!
       * \brief Set channel fsm associated to this acquisition instance
       */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm) override
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm) override
     {
         channel_fsm_ = channel_fsm;
         acquisition_->set_channel_fsm(channel_fsm);
@@ -162,7 +162,7 @@ private:
     bool bit_transition_flag_;
     bool use_CFAR_algorithm_flag_;
     unsigned int channel_;
-    std::shared_ptr<ChannelFsm> channel_fsm_;
+    std::weak_ptr<ChannelFsm> channel_fsm_;
     float threshold_;
     unsigned int doppler_max_;
     unsigned int doppler_step_;

src/algorithms/acquisition/adapters/gps_l1_ca_pcps_acquisition.cc

@@ -147,7 +147,7 @@ GpsL1CaPcpsAcquisition::GpsL1CaPcpsAcquisition(
     threshold_ = 0.0;
     doppler_step_ = 0;
     gnss_synchro_ = nullptr;
-    channel_fsm_ = nullptr;
+    
     if (in_streams_ > 1)
         {
             LOG(ERROR) << "This implementation only supports one input stream";

src/algorithms/acquisition/adapters/gps_l1_ca_pcps_acquisition.h

@@ -104,7 +104,7 @@ public:
     /*!
       * \brief Set channel fsm associated to this acquisition instance
       */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm) override
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm) override
     {
         channel_fsm_ = channel_fsm;
         acquisition_->set_channel_fsm(channel_fsm);
@@ -174,7 +174,7 @@ private:
     bool bit_transition_flag_;
     bool use_CFAR_algorithm_flag_;
     unsigned int channel_;
-    std::shared_ptr<ChannelFsm> channel_fsm_;
+    std::weak_ptr<ChannelFsm> channel_fsm_;
     float threshold_;
     unsigned int doppler_max_;
     unsigned int doppler_step_;

src/algorithms/acquisition/adapters/gps_l1_ca_pcps_acquisition_fine_doppler.cc

@@ -97,7 +97,7 @@ GpsL1CaPcpsAcquisitionFineDoppler::GpsL1CaPcpsAcquisitionFineDoppler(
     threshold_ = 0.0;
     doppler_step_ = 0;
     gnss_synchro_ = nullptr;
-    channel_fsm_ = nullptr;
+    
     if (in_streams_ > 1)
         {
             LOG(ERROR) << "This implementation only supports one input stream";

src/algorithms/acquisition/adapters/gps_l1_ca_pcps_acquisition_fine_doppler.h

@@ -97,7 +97,7 @@ public:
     /*!
       * \brief Set channel fsm associated to this acquisition instance
       */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm) override
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm) override
     {
         channel_fsm_ = channel_fsm;
         acquisition_cc_->set_channel_fsm(channel_fsm);
@@ -152,7 +152,7 @@ private:
     std::string item_type_;
     unsigned int vector_length_;
     unsigned int channel_;
-    std::shared_ptr<ChannelFsm> channel_fsm_;
+    std::weak_ptr<ChannelFsm> channel_fsm_;
     float threshold_;
     int doppler_max_;
     unsigned int doppler_step_;

src/algorithms/acquisition/adapters/gps_l1_ca_pcps_acquisition_fpga.cc

@@ -47,9 +47,15 @@
 #include <complex>  // for complex
 #include <cstring>  // for memcpy
 
-
 #define NUM_PRNs 32
 
+// the following flags are FPGA-specific and they are using arrange the values of the fft of the local code in the way the FPGA
+// expects. This arrangement is done in the initialisation to avoid consuming unnecessary clock cycles during tracking.
+#define QUANT_BITS_LOCAL_CODE 16
+#define SELECT_LSBits 0x0000FFFF         // Select the 10 LSbits out of a 20-bit word
+#define SELECT_MSBbits 0xFFFF0000        // Select the 10 MSbits out of a 20-bit word
+#define SELECT_ALL_CODE_BITS 0xFFFFFFFF  // Select a 20 bit word
+#define SHL_CODE_BITS 65536              // shift left by 10 bits
 
 GpsL1CaPcpsAcquisitionFpga::GpsL1CaPcpsAcquisitionFpga(
     ConfigurationInterface* configuration,
@@ -71,9 +77,8 @@ GpsL1CaPcpsAcquisitionFpga::GpsL1CaPcpsAcquisitionFpga(
     acq_parameters.repeat_satellite = configuration_->property(role + ".repeat_satellite", false);
     DLOG(INFO) << role << " satellite repeat = " << acq_parameters.repeat_satellite;
 
-    float downsampling_factor = configuration_->property(role + ".downsampling_factor", 4.0);
+    uint32_t downsampling_factor = configuration_->property(role + ".downsampling_factor", 4);
     acq_parameters.downsampling_factor = downsampling_factor;
-
     fs_in = fs_in / downsampling_factor;
 
     acq_parameters.fs_in = fs_in;
@@ -94,7 +99,7 @@ GpsL1CaPcpsAcquisitionFpga::GpsL1CaPcpsAcquisitionFpga(
     acq_parameters.device_name = device_name;
     acq_parameters.samples_per_ms = nsamples_total / sampled_ms;
     acq_parameters.samples_per_code = nsamples_total;
-    acq_parameters.excludelimit = static_cast<uint32_t>(std::round(static_cast<double>(fs_in) / GPS_L1_CA_CODE_RATE_HZ));
+    acq_parameters.excludelimit = static_cast<unsigned int>(1 + ceil(GPS_L1_CA_CHIP_PERIOD * static_cast<float>(fs_in)));
 
     // compute all the GPS L1 PRN Codes (this is done only once upon the class constructor in order to avoid re-computing the PRN codes every time
     // a channel is assigned)
@@ -102,8 +107,10 @@ GpsL1CaPcpsAcquisitionFpga::GpsL1CaPcpsAcquisitionFpga(
     // allocate memory to compute all the PRNs and compute all the possible codes
     auto* code = new std::complex<float>[nsamples_total];  // buffer for the local code
     auto* fft_codes_padded = static_cast<gr_complex*>(volk_gnsssdr_malloc(nsamples_total * sizeof(gr_complex), volk_gnsssdr_get_alignment()));
-    d_all_fft_codes_ = new lv_16sc_t[nsamples_total * NUM_PRNs];  // memory containing all the possible fft codes for PRN 0 to 32
+    d_all_fft_codes_ = new uint32_t[(nsamples_total * NUM_PRNs)];  // memory containing all the possible fft codes for PRN 0 to 32
-    float max;                                                    // temporary maxima search
+    float max;
+    int32_t tmp, tmp2, local_code, fft_data;
+    // temporary maxima search
     for (uint32_t PRN = 1; PRN <= NUM_PRNs; PRN++)
         {
             gps_l1_ca_code_gen_complex_sampled(code, PRN, fs_in, 0);  // generate PRN code
@@ -135,10 +142,15 @@ GpsL1CaPcpsAcquisitionFpga::GpsL1CaPcpsAcquisitionFpga(
                             max = std::abs(fft_codes_padded[i].imag());
                         }
                 }
-            for (uint32_t i = 0; i < nsamples_total; i++)  // map the FFT to the dynamic range of the fixed point values an copy to buffer containing all FFTs
+            // map the FFT to the dynamic range of the fixed point values an copy to buffer containing all FFTs
+            // and package codes in a format that is ready to be written to the FPGA
+            for (uint32_t i = 0; i < nsamples_total; i++)
                 {
-                    d_all_fft_codes_[i + nsamples_total * (PRN - 1)] = lv_16sc_t(static_cast<int32_t>(floor(fft_codes_padded[i].real() * (pow(2, 9) - 1) / max)),
+                    tmp = static_cast<int32_t>(floor(fft_codes_padded[i].real() * (pow(2, QUANT_BITS_LOCAL_CODE - 1) - 1) / max));
-                        static_cast<int32_t>(floor(fft_codes_padded[i].imag() * (pow(2, 9) - 1) / max)));
+                    tmp2 = static_cast<int32_t>(floor(fft_codes_padded[i].imag() * (pow(2, QUANT_BITS_LOCAL_CODE - 1) - 1) / max));
+                    local_code = (tmp & SELECT_LSBits) | ((tmp2 * SHL_CODE_BITS) & SELECT_MSBbits);  // put together the real part and the imaginary part
+                    fft_data = local_code & SELECT_ALL_CODE_BITS;
+                    d_all_fft_codes_[i + (nsamples_total * (PRN - 1))] = fft_data;
                 }
         }
 
@@ -146,14 +158,18 @@ GpsL1CaPcpsAcquisitionFpga::GpsL1CaPcpsAcquisitionFpga(
     acq_parameters.all_fft_codes = d_all_fft_codes_;
 
     // reference for the FPGA FFT-IFFT attenuation factor
-    acq_parameters.total_block_exp = configuration_->property(role + ".total_block_exp", 14);
+    acq_parameters.total_block_exp = configuration_->property(role + ".total_block_exp", 10);
 
+    acq_parameters.num_doppler_bins_step2 = configuration_->property(role + ".second_nbins", 4);
+    acq_parameters.doppler_step2 = configuration_->property(role + ".second_doppler_step", 125.0);
+    acq_parameters.make_2_steps = configuration_->property(role + ".make_two_steps", false);
+    acq_parameters.max_num_acqs = configuration_->property(role + ".max_num_acqs", 2);
     acquisition_fpga_ = pcps_make_acquisition_fpga(acq_parameters);
 
     channel_ = 0;
     doppler_step_ = 0;
     gnss_synchro_ = nullptr;
-    channel_fsm_ = nullptr;
+    
     // temporary buffers that we can delete
     delete[] code;
     delete fft_if;

src/algorithms/acquisition/adapters/gps_l1_ca_pcps_acquisition_fpga.h

@@ -35,6 +35,7 @@
 #ifndef GNSS_SDR_GPS_L1_CA_PCPS_ACQUISITION_FPGA_H_
 #define GNSS_SDR_GPS_L1_CA_PCPS_ACQUISITION_FPGA_H_
 
+
 #include "channel_fsm.h"
 #include "pcps_acquisition_fpga.h"
 #include <gnuradio/runtime_types.h>  // for basic_block_sptr, top_block_sptr
@@ -100,9 +101,9 @@ public:
     }
 
     /*!
-      * \brief Set channel fsm associated to this acquisition instance
+     * \brief Set channel fsm associated to this acquisition instance
-      */
+     */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm) override
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm) override
     {
         channel_fsm_ = channel_fsm;
         acquisition_fpga_->set_channel_fsm(channel_fsm);
@@ -159,14 +160,14 @@ private:
     ConfigurationInterface* configuration_;
     pcps_acquisition_fpga_sptr acquisition_fpga_;
     uint32_t channel_;
-    std::shared_ptr<ChannelFsm> channel_fsm_;
+    std::weak_ptr<ChannelFsm> channel_fsm_;
     uint32_t doppler_max_;
     uint32_t doppler_step_;
     Gnss_Synchro* gnss_synchro_;
     std::string role_;
     unsigned int in_streams_;
     unsigned int out_streams_;
-    lv_16sc_t* d_all_fft_codes_;  // memory that contains all the code ffts
+    uint32_t* d_all_fft_codes_;  // memory that contains all the code ffts
 };
 
 #endif /* GNSS_SDR_GPS_L1_CA_PCPS_ACQUISITION_FPGA_H_ */

src/algorithms/acquisition/adapters/gps_l1_ca_pcps_assisted_acquisition.cc

@@ -89,7 +89,7 @@ GpsL1CaPcpsAssistedAcquisition::GpsL1CaPcpsAssistedAcquisition(
     threshold_ = 0.0;
     doppler_step_ = 0;
     gnss_synchro_ = nullptr;
-    channel_fsm_ = nullptr;
+    
     if (in_streams_ > 1)
         {
             LOG(ERROR) << "This implementation only supports one input stream";

src/algorithms/acquisition/adapters/gps_l1_ca_pcps_assisted_acquisition.h

@@ -97,7 +97,7 @@ public:
     /*!
       * \brief Set channel fsm associated to this acquisition instance
       */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm) override
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm) override
     {
         channel_fsm_ = channel_fsm;
         acquisition_cc_->set_channel_fsm(channel_fsm);
@@ -149,7 +149,7 @@ private:
     unsigned int vector_length_;
     //unsigned int satellite_;
     unsigned int channel_;
-    std::shared_ptr<ChannelFsm> channel_fsm_;
+    std::weak_ptr<ChannelFsm> channel_fsm_;
     float threshold_;
     int doppler_max_;
     unsigned int doppler_step_;

src/algorithms/acquisition/adapters/gps_l1_ca_pcps_opencl_acquisition.cc

@@ -105,7 +105,7 @@ GpsL1CaPcpsOpenClAcquisition::GpsL1CaPcpsOpenClAcquisition(
     threshold_ = 0.0;
     doppler_step_ = 0;
     gnss_synchro_ = nullptr;
-    channel_fsm_ = nullptr;
+    
     if (in_streams_ > 1)
         {
             LOG(ERROR) << "This implementation only supports one input stream";

src/algorithms/acquisition/adapters/gps_l1_ca_pcps_opencl_acquisition.h

@@ -96,7 +96,7 @@ public:
     /*!
       * \brief Set channel fsm associated to this acquisition instance
       */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm) override
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm) override
     {
         channel_fsm_ = channel_fsm;
         acquisition_cc_->set_channel_fsm(channel_fsm);
@@ -154,7 +154,7 @@ private:
     unsigned int code_length_;
     bool bit_transition_flag_;
     unsigned int channel_;
-    std::shared_ptr<ChannelFsm> channel_fsm_;
+    std::weak_ptr<ChannelFsm> channel_fsm_;
     float threshold_;
     unsigned int doppler_max_;
     unsigned int doppler_step_;

src/algorithms/acquisition/adapters/gps_l1_ca_pcps_quicksync_acquisition.cc

@@ -137,7 +137,7 @@ GpsL1CaPcpsQuickSyncAcquisition::GpsL1CaPcpsQuickSyncAcquisition(
     threshold_ = 0.0;
     doppler_step_ = 0;
     gnss_synchro_ = nullptr;
-    channel_fsm_ = nullptr;
+    
     if (in_streams_ > 1)
         {
             LOG(ERROR) << "This implementation only supports one input stream";

src/algorithms/acquisition/adapters/gps_l1_ca_pcps_quicksync_acquisition.h

@@ -98,7 +98,7 @@ public:
     /*!
       * \brief Set channel fsm associated to this acquisition instance
       */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm) override
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm) override
     {
         channel_fsm_ = channel_fsm;
         acquisition_cc_->set_channel_fsm(channel_fsm);
@@ -160,7 +160,7 @@ private:
     unsigned int code_length_;
     bool bit_transition_flag_;
     unsigned int channel_;
-    std::shared_ptr<ChannelFsm> channel_fsm_;
+    std::weak_ptr<ChannelFsm> channel_fsm_;
     float threshold_;
     unsigned int doppler_max_;
     unsigned int doppler_step_;

src/algorithms/acquisition/adapters/gps_l1_ca_pcps_tong_acquisition.cc

@@ -99,7 +99,7 @@ GpsL1CaPcpsTongAcquisition::GpsL1CaPcpsTongAcquisition(
     threshold_ = 0.0;
     doppler_step_ = 0;
     gnss_synchro_ = nullptr;
-    channel_fsm_ = nullptr;
+    
     if (in_streams_ > 1)
         {
             LOG(ERROR) << "This implementation only supports one input stream";

src/algorithms/acquisition/adapters/gps_l1_ca_pcps_tong_acquisition.h

@@ -97,7 +97,7 @@ public:
     /*!
       * \brief Set channel fsm associated to this acquisition instance
       */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm) override
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm) override
     {
         channel_fsm_ = channel_fsm;
         acquisition_cc_->set_channel_fsm(channel_fsm);
@@ -158,7 +158,7 @@ private:
     unsigned int vector_length_;
     unsigned int code_length_;
     unsigned int channel_;
-    std::shared_ptr<ChannelFsm> channel_fsm_;
+    std::weak_ptr<ChannelFsm> channel_fsm_;
     float threshold_;
     unsigned int doppler_max_;
     unsigned int doppler_step_;

src/algorithms/acquisition/adapters/gps_l2_m_pcps_acquisition.cc

@@ -151,7 +151,7 @@ GpsL2MPcpsAcquisition::GpsL2MPcpsAcquisition(
     threshold_ = 0.0;
     doppler_step_ = 0;
     gnss_synchro_ = nullptr;
-    channel_fsm_ = nullptr;
+    
     num_codes_ = acq_parameters_.sampled_ms / acq_parameters_.ms_per_code;
     if (in_streams_ > 1)
         {

src/algorithms/acquisition/adapters/gps_l2_m_pcps_acquisition.h

@@ -101,7 +101,7 @@ public:
     /*!
       * \brief Set channel fsm associated to this acquisition instance
       */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm) override
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm) override
     {
         channel_fsm_ = channel_fsm;
         acquisition_->set_channel_fsm(channel_fsm);
@@ -171,7 +171,7 @@ private:
     bool bit_transition_flag_;
     bool use_CFAR_algorithm_flag_;
     unsigned int channel_;
-    std::shared_ptr<ChannelFsm> channel_fsm_;
+    std::weak_ptr<ChannelFsm> channel_fsm_;
     float threshold_;
     unsigned int doppler_max_;
     unsigned int doppler_step_;

src/algorithms/acquisition/adapters/gps_l2_m_pcps_acquisition_fpga.cc

@@ -47,7 +47,11 @@
 #include <cstring>  // for memcpy
 
 #define NUM_PRNs 32
-
+#define QUANT_BITS_LOCAL_CODE 16
+#define SELECT_LSBits 0x0000FFFF         // Select the 10 LSbits out of a 20-bit word
+#define SELECT_MSBbits 0xFFFF0000        // Select the 10 MSbits out of a 20-bit word
+#define SELECT_ALL_CODE_BITS 0xFFFFFFFF  // Select a 20 bit word
+#define SHL_CODE_BITS 65536              // shift left by 10 bits
 
 GpsL2MPcpsAcquisitionFpga::GpsL2MPcpsAcquisitionFpga(
     ConfigurationInterface* configuration,
@@ -102,8 +106,11 @@ GpsL2MPcpsAcquisitionFpga::GpsL2MPcpsAcquisitionFpga(
     // allocate memory to compute all the PRNs and compute all the possible codes
     auto* code = new std::complex<float>[nsamples_total];  // buffer for the local code
     auto* fft_codes_padded = static_cast<gr_complex*>(volk_gnsssdr_malloc(nsamples_total * sizeof(gr_complex), volk_gnsssdr_get_alignment()));
-    d_all_fft_codes_ = new lv_16sc_t[nsamples_total * NUM_PRNs];  // memory containing all the possible fft codes for PRN 0 to 32
+    //d_all_fft_codes_ = new lv_16sc_t[nsamples_total * NUM_PRNs];  // memory containing all the possible fft codes for PRN 0 to 32
-    float max;                                                    // temporary maxima search
+    d_all_fft_codes_ = new uint32_t[(nsamples_total * NUM_PRNs)];  // memory containing all the possible fft codes for PRN 0 to 32
+    float max;                                                     // temporary maxima search
+    int32_t tmp, tmp2, local_code, fft_data;
+
     for (unsigned int PRN = 1; PRN <= NUM_PRNs; PRN++)
         {
             gps_l2c_m_code_gen_complex_sampled(code, PRN, fs_in_);
@@ -127,10 +134,18 @@ GpsL2MPcpsAcquisitionFpga::GpsL2MPcpsAcquisitionFpga(
                             max = std::abs(fft_codes_padded[i].imag());
                         }
                 }
-            for (unsigned int i = 0; i < nsamples_total; i++)  // map the FFT to the dynamic range of the fixed point values an copy to buffer containing all FFTs
+            // map the FFT to the dynamic range of the fixed point values an copy to buffer containing all FFTs
+            // and package codes in a format that is ready to be written to the FPGA
+            for (uint32_t i = 0; i < nsamples_total; i++)
                 {
-                    d_all_fft_codes_[i + nsamples_total * (PRN - 1)] = lv_16sc_t(static_cast<int>(floor(fft_codes_padded[i].real() * (pow(2, 7) - 1) / max)),
+                    tmp = static_cast<int32_t>(floor(fft_codes_padded[i].real() * (pow(2, QUANT_BITS_LOCAL_CODE - 1) - 1) / max));
-                        static_cast<int>(floor(fft_codes_padded[i].imag() * (pow(2, 7) - 1) / max)));
+                    tmp2 = static_cast<int32_t>(floor(fft_codes_padded[i].imag() * (pow(2, QUANT_BITS_LOCAL_CODE - 1) - 1) / max));
+                    local_code = (tmp & SELECT_LSBits) | ((tmp2 * SHL_CODE_BITS) & SELECT_MSBbits);  // put together the real part and the imaginary part
+                    fft_data = local_code & SELECT_ALL_CODE_BITS;
+                    d_all_fft_codes_[i + (nsamples_total * (PRN - 1))] = fft_data;
+
+                    // d_all_fft_codes_[i + nsamples_total * (PRN - 1)] = lv_16sc_t(static_cast<int32_t>(floor(fft_codes_padded[i].real() * (pow(2, QUANT_BITS_LOCAL_CODE - 1) - 1) / max)),
+                    // static_cast<int32_t>(floor(fft_codes_padded[i].imag() * (pow(2, QUANT_BITS_LOCAL_CODE - 1) - 1) / max)));
                 }
         }
 
@@ -146,7 +161,7 @@ GpsL2MPcpsAcquisitionFpga::GpsL2MPcpsAcquisitionFpga(
     channel_ = 0;
     doppler_step_ = 0;
     gnss_synchro_ = nullptr;
-    channel_fsm_ = nullptr;
+    
 
     threshold_ = 0.0;
 }

src/algorithms/acquisition/adapters/gps_l2_m_pcps_acquisition_fpga.h

@@ -100,7 +100,7 @@ public:
     /*!
       * \brief Set channel fsm associated to this acquisition instance
       */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm) override
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm) override
     {
         channel_fsm_ = channel_fsm;
         acquisition_fpga_->set_channel_fsm(channel_fsm);
@@ -158,7 +158,7 @@ private:
     pcps_acquisition_fpga_sptr acquisition_fpga_;
     std::string item_type_;
     unsigned int channel_;
-    std::shared_ptr<ChannelFsm> channel_fsm_;
+    std::weak_ptr<ChannelFsm> channel_fsm_;
     float threshold_;
     unsigned int doppler_max_;
     unsigned int doppler_step_;
@@ -169,7 +169,7 @@ private:
     unsigned int in_streams_;
     unsigned int out_streams_;
 
-    lv_16sc_t* d_all_fft_codes_;  // memory that contains all the code ffts
+    uint32_t* d_all_fft_codes_;  // memory that contains all the code ffts
 
     //float calculate_threshold(float pfa);
 };

src/algorithms/acquisition/adapters/gps_l5i_pcps_acquisition.cc

@@ -147,7 +147,7 @@ GpsL5iPcpsAcquisition::GpsL5iPcpsAcquisition(
     threshold_ = 0.0;
     doppler_step_ = 0;
     gnss_synchro_ = nullptr;
-    channel_fsm_ = nullptr;
+    
     if (in_streams_ > 1)
         {
             LOG(ERROR) << "This implementation only supports one input stream";

src/algorithms/acquisition/adapters/gps_l5i_pcps_acquisition.h

@@ -101,7 +101,7 @@ public:
     /*!
       * \brief Set channel fsm associated to this acquisition instance
       */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm) override
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm) override
     {
         channel_fsm_ = channel_fsm;
         acquisition_->set_channel_fsm(channel_fsm);
@@ -170,7 +170,7 @@ private:
     bool bit_transition_flag_;
     bool use_CFAR_algorithm_flag_;
     unsigned int channel_;
-    std::shared_ptr<ChannelFsm> channel_fsm_;
+    std::weak_ptr<ChannelFsm> channel_fsm_;
     float threshold_;
     unsigned int doppler_max_;
     unsigned int doppler_step_;

src/algorithms/acquisition/adapters/gps_l5i_pcps_acquisition_fpga.cc

@@ -49,6 +49,14 @@
 
 #define NUM_PRNs 32
 
+// the following flags are FPGA-specific and they are using arrange the values of the fft of the local code in the way the FPGA
+// expects. This arrangement is done in the initialisation to avoid consuming unnecessary clock cycles during tracking.
+#define QUANT_BITS_LOCAL_CODE 16
+#define SELECT_LSBits 0x0000FFFF         // Select the 10 LSbits out of a 20-bit word
+#define SELECT_MSBbits 0xFFFF0000        // Select the 10 MSbits out of a 20-bit word
+#define SELECT_ALL_CODE_BITS 0xFFFFFFFF  // Select a 20 bit word
+#define SHL_CODE_BITS 65536              // shift left by 10 bits
+
 
 GpsL5iPcpsAcquisitionFpga::GpsL5iPcpsAcquisitionFpga(
     ConfigurationInterface* configuration,
@@ -70,7 +78,7 @@ GpsL5iPcpsAcquisitionFpga::GpsL5iPcpsAcquisitionFpga(
     acq_parameters.repeat_satellite = configuration_->property(role + ".repeat_satellite", false);
     DLOG(INFO) << role << " satellite repeat = " << acq_parameters.repeat_satellite;
 
-    float downsampling_factor = configuration_->property(role + ".downsampling_factor", 1.0);
+    uint32_t downsampling_factor = configuration_->property(role + ".downsampling_factor", 1);
     acq_parameters.downsampling_factor = downsampling_factor;
 
     fs_in = fs_in / downsampling_factor;
@@ -96,16 +104,18 @@ GpsL5iPcpsAcquisitionFpga::GpsL5iPcpsAcquisitionFpga(
     acq_parameters.samples_per_ms = nsamples_total / sampled_ms;
     acq_parameters.samples_per_code = nsamples_total;
 
-    acq_parameters.excludelimit = static_cast<uint32_t>(ceil((1.0 / GPS_L5I_CODE_RATE_HZ) * static_cast<float>(acq_parameters.fs_in)));
+    acq_parameters.excludelimit = static_cast<unsigned int>(1 + ceil((1.0 / GPS_L5I_CODE_RATE_HZ) * static_cast<float>(fs_in)));
 
     // compute all the GPS L5 PRN Codes (this is done only once upon the class constructor in order to avoid re-computing the PRN codes every time
     // a channel is assigned)
     auto* fft_if = new gr::fft::fft_complex(nsamples_total, true);  // Direct FFT
     auto* code = new gr_complex[nsamples_total];
     auto* fft_codes_padded = static_cast<gr_complex*>(volk_gnsssdr_malloc(nsamples_total * sizeof(gr_complex), volk_gnsssdr_get_alignment()));
-    d_all_fft_codes_ = new lv_16sc_t[nsamples_total * NUM_PRNs];  // memory containing all the possible fft codes for PRN 0 to 32
+    d_all_fft_codes_ = new uint32_t[(nsamples_total * NUM_PRNs)];  // memory containing all the possible fft codes for PRN 0 to 32
 
     float max;  // temporary maxima search
+    int32_t tmp, tmp2, local_code, fft_data;
+
     for (uint32_t PRN = 1; PRN <= NUM_PRNs; PRN++)
         {
             gps_l5i_code_gen_complex_sampled(code, PRN, fs_in);
@@ -136,24 +146,33 @@ GpsL5iPcpsAcquisitionFpga::GpsL5iPcpsAcquisitionFpga(
                             max = std::abs(fft_codes_padded[i].imag());
                         }
                 }
-            for (uint32_t i = 0; i < nsamples_total; i++)  // map the FFT to the dynamic range of the fixed point values an copy to buffer containing all FFTs
+            // map the FFT to the dynamic range of the fixed point values an copy to buffer containing all FFTs
+            // and package codes in a format that is ready to be written to the FPGA
+            for (uint32_t i = 0; i < nsamples_total; i++)
                 {
-                    d_all_fft_codes_[i + nsamples_total * (PRN - 1)] = lv_16sc_t(static_cast<int32_t>(floor(fft_codes_padded[i].real() * (pow(2, 9) - 1) / max)),
+                    tmp = static_cast<int32_t>(floor(fft_codes_padded[i].real() * (pow(2, QUANT_BITS_LOCAL_CODE - 1) - 1) / max));
-                        static_cast<int32_t>(floor(fft_codes_padded[i].imag() * (pow(2, 9) - 1) / max)));
+                    tmp2 = static_cast<int32_t>(floor(fft_codes_padded[i].imag() * (pow(2, QUANT_BITS_LOCAL_CODE - 1) - 1) / max));
+                    local_code = (tmp & SELECT_LSBits) | ((tmp2 * SHL_CODE_BITS) & SELECT_MSBbits);  // put together the real part and the imaginary part
+                    fft_data = local_code & SELECT_ALL_CODE_BITS;
+                    d_all_fft_codes_[i + (nsamples_total * (PRN - 1))] = fft_data;
                 }
         }
 
     acq_parameters.all_fft_codes = d_all_fft_codes_;
 
     // reference for the FPGA FFT-IFFT attenuation factor
-    acq_parameters.total_block_exp = configuration_->property(role + ".total_block_exp", 14);
+    acq_parameters.total_block_exp = configuration_->property(role + ".total_block_exp", 13);
 
+    acq_parameters.num_doppler_bins_step2 = configuration_->property(role + ".second_nbins", 4);
+    acq_parameters.doppler_step2 = configuration_->property(role + ".second_doppler_step", 125.0);
+    acq_parameters.make_2_steps = configuration_->property(role + ".make_two_steps", false);
+    acq_parameters.max_num_acqs = configuration_->property(role + ".max_num_acqs", 2);
     acquisition_fpga_ = pcps_make_acquisition_fpga(acq_parameters);
 
     channel_ = 0;
     doppler_step_ = 0;
     gnss_synchro_ = nullptr;
-    channel_fsm_ = nullptr;
+
     // temporary buffers that we can delete
     delete[] code;
     delete fft_if;

src/algorithms/acquisition/adapters/gps_l5i_pcps_acquisition_fpga.h

@@ -101,11 +101,12 @@ public:
     /*!
       * \brief Set channel fsm associated to this acquisition instance
       */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm) override
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm) override
     {
         channel_fsm_ = channel_fsm;
         acquisition_fpga_->set_channel_fsm(channel_fsm);
     }
+
     /*!
      * \brief Set statistics threshold of PCPS algorithm
      */
@@ -158,7 +159,7 @@ private:
     pcps_acquisition_fpga_sptr acquisition_fpga_;
     std::string item_type_;
     uint32_t channel_;
-    std::shared_ptr<ChannelFsm> channel_fsm_;
+    std::weak_ptr<ChannelFsm> channel_fsm_;
     uint32_t doppler_max_;
     uint32_t doppler_step_;
     std::string dump_filename_;
@@ -167,7 +168,7 @@ private:
     unsigned int in_streams_;
     unsigned int out_streams_;
 
-    lv_16sc_t* d_all_fft_codes_;  // memory that contains all the code ffts
+    uint32_t* d_all_fft_codes_;  // memory that contains all the code ffts
 
     float calculate_threshold(float pfa);
 };

src/algorithms/acquisition/gnuradio_blocks/galileo_e5a_noncoherent_iq_acquisition_caf_cc.h

@@ -100,7 +100,7 @@ private:
         int doppler_offset);
     float estimate_input_power(gr_complex* in);
 
-    std::shared_ptr<ChannelFsm> d_channel_fsm;
+    std::weak_ptr<ChannelFsm> d_channel_fsm;
     int64_t d_fs_in;
     int d_samples_per_ms;
     int d_sampled_ms;
@@ -216,7 +216,7 @@ public:
     /*!
       * \brief Set channel fsm associated to this acquisition instance
       */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm)
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm)
     {
         d_channel_fsm = channel_fsm;
     }

src/algorithms/acquisition/gnuradio_blocks/galileo_pcps_8ms_acquisition_cc.h

@@ -118,7 +118,7 @@ private:
     int32_t d_state;
     bool d_dump;
     uint32_t d_channel;
-    std::shared_ptr<ChannelFsm> d_channel_fsm;
+    std::weak_ptr<ChannelFsm> d_channel_fsm;
     std::string d_dump_filename;
 
 public:
@@ -186,7 +186,7 @@ public:
     /*!
       * \brief Set channel fsm associated to this acquisition instance
       */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm)
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm)
     {
         d_channel_fsm = channel_fsm;
     }

src/algorithms/acquisition/gnuradio_blocks/pcps_acquisition.cc

@@ -429,10 +429,11 @@ void pcps_acquisition::send_positive_acquisition()
                << ", magnitude " << d_mag
                << ", input signal power " << d_input_power;
     d_positive_acq = 1;
-    if (d_channel_fsm)
+
+    if (!d_channel_fsm.expired())
         {
             //the channel FSM is set, so, notify it directly the positive acquisition to minimize delays
-            d_channel_fsm->Event_valid_acquisition();
+            d_channel_fsm.lock()->Event_valid_acquisition();
         }
     else
         {

src/algorithms/acquisition/gnuradio_blocks/pcps_acquisition.h

@@ -124,7 +124,7 @@ private:
     int64_t d_old_freq;
     int32_t d_state;
     uint32_t d_channel;
-    std::shared_ptr<ChannelFsm> d_channel_fsm;
+    std::weak_ptr<ChannelFsm> d_channel_fsm;
     uint32_t d_doppler_step;
     float d_doppler_center_step_two;
     uint32_t d_num_noncoherent_integrations_counter;
@@ -213,7 +213,7 @@ public:
     /*!
       * \brief Set channel fsm associated to this acquisition instance
       */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm)
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm)
     {
         d_channel_fsm = channel_fsm;
     }

src/algorithms/acquisition/gnuradio_blocks/pcps_acquisition_fine_doppler_cc.h

@@ -122,7 +122,7 @@ private:
     int d_n_samples_in_buffer;
     bool d_dump;
     unsigned int d_channel;
-    std::shared_ptr<ChannelFsm> d_channel_fsm;
+    std::weak_ptr<ChannelFsm> d_channel_fsm;
 
     std::string d_dump_filename;
 
@@ -189,7 +189,7 @@ public:
     /*!
       * \brief Set channel fsm associated to this acquisition instance
       */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm)
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm)
     {
         d_channel_fsm = channel_fsm;
     }

src/algorithms/acquisition/gnuradio_blocks/pcps_acquisition_fpga.cc

@@ -34,6 +34,7 @@
 
 #include "pcps_acquisition_fpga.h"
 #include "gnss_synchro.h"
+//#include <boost/chrono.hpp>
 #include <glog/logging.h>
 #include <cmath>     // for ceil
 #include <iostream>  // for operator<<
@@ -42,7 +43,6 @@
 
 #define AQ_DOWNSAMPLING_DELAY 40  // delay due to the downsampling filter in the acquisition
 
-
 pcps_acquisition_fpga_sptr pcps_make_acquisition_fpga(pcpsconf_fpga_t conf_)
 {
     return pcps_acquisition_fpga_sptr(new pcps_acquisition_fpga(std::move(conf_)));
@@ -52,7 +52,7 @@ pcps_acquisition_fpga_sptr pcps_make_acquisition_fpga(pcpsconf_fpga_t conf_)
 pcps_acquisition_fpga::pcps_acquisition_fpga(pcpsconf_fpga_t conf_)
 {
     acq_parameters = std::move(conf_);
-    d_sample_counter = 0ULL;  // SAMPLE COUNTER
+    d_sample_counter = 0ULL;  // Sample Counter
     d_active = false;
     d_state = 0;
     d_fft_size = acq_parameters.samples_per_code;
@@ -71,16 +71,21 @@ pcps_acquisition_fpga::pcps_acquisition_fpga(pcpsconf_fpga_t conf_)
 
     d_total_block_exp = acq_parameters.total_block_exp;
 
+    d_make_2_steps = acq_parameters.make_2_steps;
+    d_num_doppler_bins_step2 = acq_parameters.num_doppler_bins_step2;
+    d_doppler_step2 = acq_parameters.doppler_step2;
+    d_doppler_center_step_two = 0.0;
+
+    d_doppler_max = acq_parameters.doppler_max;
+
+    d_max_num_acqs = acq_parameters.max_num_acqs;
+
     acquisition_fpga = std::make_shared<Fpga_Acquisition>(acq_parameters.device_name, acq_parameters.code_length, acq_parameters.doppler_max, d_fft_size,
         acq_parameters.fs_in, acq_parameters.sampled_ms, acq_parameters.select_queue_Fpga, acq_parameters.all_fft_codes, acq_parameters.excludelimit);
 }
 
 
-pcps_acquisition_fpga::~pcps_acquisition_fpga()
+pcps_acquisition_fpga::~pcps_acquisition_fpga() = default;
-{
-    acquisition_fpga->free();
-}
-
 
 void pcps_acquisition_fpga::set_local_code()
 {
@@ -100,9 +105,7 @@ void pcps_acquisition_fpga::init()
     d_mag = 0.0;
     d_input_power = 0.0;
 
-    d_num_doppler_bins = static_cast<uint32_t>(std::ceil(static_cast<double>(static_cast<int32_t>(acq_parameters.doppler_max) - static_cast<int32_t>(-acq_parameters.doppler_max)) / static_cast<double>(d_doppler_step))) + 1;
+    d_num_doppler_bins = static_cast<uint32_t>(std::ceil(static_cast<double>(static_cast<int32_t>(d_doppler_max) - static_cast<int32_t>(-d_doppler_max)) / static_cast<double>(d_doppler_step))) + 1;
-
-    acquisition_fpga->init();
 }
 
 
@@ -144,7 +147,7 @@ void pcps_acquisition_fpga::send_positive_acquisition()
                << ", input signal power " << d_input_power;
 
     //the channel FSM is set, so, notify it directly the positive acquisition to minimize delays
-    d_channel_fsm->Event_valid_acquisition();
+    d_channel_fsm.lock()->Event_valid_acquisition();
 }
 
 
@@ -163,65 +166,60 @@ void pcps_acquisition_fpga::send_negative_acquisition()
 
     if (acq_parameters.repeat_satellite == true)
         {
-            d_channel_fsm->Event_failed_acquisition_repeat();
+            d_channel_fsm.lock()->Event_failed_acquisition_repeat();
         }
     else
         {
-            d_channel_fsm->Event_failed_acquisition_no_repeat();
+            d_channel_fsm.lock()->Event_failed_acquisition_no_repeat();
         }
 }
 
-
+void pcps_acquisition_fpga::acquisition_core(uint32_t num_doppler_bins, uint32_t doppler_step, int32_t doppler_min)
-void pcps_acquisition_fpga::set_active(bool active)
 {
-    d_active = active;
-
-    // initialize acquisition algorithm
     uint32_t indext = 0U;
     float firstpeak = 0.0;
     float secondpeak = 0.0;
     uint32_t total_block_exp;
-
-    d_input_power = 0.0;
-    d_mag = 0.0;
-
-    int32_t doppler;
-
-    DLOG(INFO) << "Channel: " << d_channel
-               << " , doing acquisition of satellite: " << d_gnss_synchro->System << " " << d_gnss_synchro->PRN
-               << " ,sample stamp: " << d_sample_counter << ", threshold: "
-               << d_threshold << ", doppler_max: " << acq_parameters.doppler_max
-               << ", doppler_step: " << d_doppler_step
-               // no CFAR algorithm in the FPGA
-               << ", use_CFAR_algorithm_flag: false";
-
     uint64_t initial_sample;
-
+    int32_t doppler;
-    acquisition_fpga->configure_acquisition();
+    acquisition_fpga->set_doppler_sweep(num_doppler_bins, doppler_step, doppler_min);
-    acquisition_fpga->set_doppler_sweep(d_num_doppler_bins);
-    acquisition_fpga->write_local_code();
-    acquisition_fpga->set_block_exp(d_total_block_exp);
     acquisition_fpga->run_acquisition();
-    acquisition_fpga->read_acquisition_results(&indext, &firstpeak, &secondpeak, &initial_sample, &d_input_power, &d_doppler_index, &total_block_exp);
+    acquisition_fpga->read_acquisition_results(&indext,
+        &firstpeak,
+        &secondpeak,
+        &initial_sample,
+        &d_input_power,
+        &d_doppler_index,
+        &total_block_exp);
+
+    doppler = static_cast<int32_t>(doppler_min) + doppler_step * (d_doppler_index - 1);
 
     if (total_block_exp > d_total_block_exp)
         {
             // if the attenuation factor of the FPGA FFT-IFFT is smaller than the reference attenuation factor then we need to update the reference attenuation factor
             std::cout << "changing blk exp..... d_total_block_exp = " << d_total_block_exp << " total_block_exp = " << total_block_exp << " chan = " << d_channel << std::endl;
             d_total_block_exp = total_block_exp;
-        }
+            d_test_statistics = 0;
-
-    doppler = -static_cast<int32_t>(acq_parameters.doppler_max) + d_doppler_step * (d_doppler_index - 1);
-
-    if (secondpeak > 0)
-        {
-            d_test_statistics = firstpeak / secondpeak;
         }
     else
         {
-            d_test_statistics = 0.0;
+            if (secondpeak > 0)
+                {
+                    d_test_statistics = firstpeak / secondpeak;
+                }
+            else
+                {
+                    d_test_statistics = 0.0;
+                }
         }
 
+    // debug
+    //    if (d_test_statistics > d_threshold)
+    //        {
+    //            printf("firstpeak = %f, secondpeak = %f, test_statistics = %f reported block exp = %d PRN = %d inext = %d, initial_sample = %ld doppler = %d\n", firstpeak, secondpeak, d_test_statistics, (int)total_block_exp, (int)d_gnss_synchro->PRN, (int)indext, (long int)initial_sample, (int)doppler);
+    //            printf("doppler_min = %d doppler_step = %d num_doppler_bins = %d\n", (int)doppler_min, (int)doppler_step, (int)num_doppler_bins);
+    //        }
+
     d_gnss_synchro->Acq_doppler_hz = static_cast<double>(doppler);
     d_sample_counter = initial_sample;
 
@@ -230,7 +228,7 @@ void pcps_acquisition_fpga::set_active(bool active)
             if (d_downsampling_factor > 1)
                 {
                     d_gnss_synchro->Acq_delay_samples = static_cast<double>(d_downsampling_factor * (indext));
-                    d_gnss_synchro->Acq_samplestamp_samples = d_downsampling_factor * d_sample_counter - 44;  //33; //41; //+ 81*0.5; // delay due to the downsampling filter in the acquisition
+                    d_gnss_synchro->Acq_samplestamp_samples = d_downsampling_factor * static_cast<uint64_t>(d_sample_counter) - static_cast<uint64_t>(44);  //33; //41; //+ 81*0.5; // delay due to the downsampling filter in the acquisition
                 }
             else
                 {
@@ -243,18 +241,82 @@ void pcps_acquisition_fpga::set_active(bool active)
             d_gnss_synchro->Acq_delay_samples = static_cast<double>(indext);
             d_gnss_synchro->Acq_samplestamp_samples = d_sample_counter;  // delay due to the downsampling filter in the acquisition
         }
+}
 
-    if (d_test_statistics > d_threshold)
+
+void pcps_acquisition_fpga::set_active(bool active)
+{
+    d_active = active;
+
+    d_input_power = 0.0;
+
+    d_mag = 0.0;
+
+    DLOG(INFO) << "Channel: " << d_channel
+               << " , doing acquisition of satellite: " << d_gnss_synchro->System << " " << d_gnss_synchro->PRN
+               << " ,sample stamp: " << d_sample_counter << ", threshold: "
+               << d_threshold << ", doppler_max: " << d_doppler_max
+               << ", doppler_step: " << d_doppler_step
+               // no CFAR algorithm in the FPGA
+               << ", use_CFAR_algorithm_flag: false";
+
+    acquisition_fpga->open_device();
+    acquisition_fpga->configure_acquisition();
+    acquisition_fpga->write_local_code();
+    acquisition_fpga->set_block_exp(d_total_block_exp);
+
+    acquisition_core(d_num_doppler_bins, d_doppler_step, -d_doppler_max);
+    if (!d_make_2_steps)
         {
-            d_active = false;
+            acquisition_fpga->close_device();
-            send_positive_acquisition();
+            if (d_test_statistics > d_threshold)
-            d_state = 0;  // Positive acquisition
+                {
+                    d_active = false;
+                    send_positive_acquisition();
+                    d_state = 0;  // Positive acquisition
+                }
+            else
+                {
+                    d_state = 0;
+                    d_active = false;
+                    send_negative_acquisition();
+                }
         }
     else
         {
-            d_state = 0;
+            if (d_test_statistics > d_threshold)
-            d_active = false;
+                {
-            send_negative_acquisition();
+                    d_doppler_center_step_two = static_cast<float>(d_gnss_synchro->Acq_doppler_hz);
+
+                    uint32_t num_second_acq = 1;
+
+                    while (num_second_acq < d_max_num_acqs)
+                        {
+                            acquisition_core(d_num_doppler_bins_step2, d_doppler_step2, d_doppler_center_step_two - static_cast<float>(floor(d_num_doppler_bins_step2 / 2.0)) * d_doppler_step2);
+                            if (d_test_statistics > d_threshold)
+                                {
+                                    d_active = false;
+                                    send_positive_acquisition();
+                                    d_state = 0;  // Positive acquisition
+                                    break;
+                                }
+                            num_second_acq = num_second_acq + 1;
+                        }
+                    acquisition_fpga->close_device();
+                    if (d_test_statistics <= d_threshold)
+                        {
+                            d_state = 0;
+                            d_active = false;
+                            send_negative_acquisition();
+                        }
+                }
+            else
+                {
+                    acquisition_fpga->close_device();
+                    d_state = 0;
+                    d_active = false;
+                    send_negative_acquisition();
+                }
         }
 }
 
@@ -262,11 +324,7 @@ void pcps_acquisition_fpga::set_active(bool active)
 void pcps_acquisition_fpga::reset_acquisition(void)
 {
     // this function triggers a HW reset of the FPGA PL.
+    acquisition_fpga->open_device();
     acquisition_fpga->reset_acquisition();
-}
+    acquisition_fpga->close_device();
-
-
-void pcps_acquisition_fpga::read_fpga_total_scale_factor(uint32_t* total_scale_factor, uint32_t* fw_scale_factor)
-{
-    acquisition_fpga->read_fpga_total_scale_factor(total_scale_factor, fw_scale_factor);
 }

src/algorithms/acquisition/gnuradio_blocks/pcps_acquisition_fpga.h

@@ -62,11 +62,16 @@ typedef struct
     int32_t code_length;
     uint32_t select_queue_Fpga;
     std::string device_name;
-    lv_16sc_t* all_fft_codes;  // memory that contains all the code ffts
+    uint32_t* all_fft_codes; // pointer to memory that contains all the code ffts
-    float downsampling_factor;
+    //float downsampling_factor;
+    uint32_t downsampling_factor;
     uint32_t total_block_exp;
     uint32_t excludelimit;
+    bool make_2_steps;
+    uint32_t num_doppler_bins_step2;
+    float doppler_step2;
     bool repeat_satellite;
+    uint32_t max_num_acqs;
 } pcpsconf_fpga_t;
 
 class pcps_acquisition_fpga;
@@ -95,6 +100,8 @@ private:
 
     float first_vs_second_peak_statistic(uint32_t& indext, int32_t& doppler, uint32_t num_doppler_bins, int32_t doppler_max, int32_t doppler_step);
 
+    void acquisition_core(uint32_t num_doppler_bins, uint32_t doppler_step, int32_t doppler_max);
+
     pcpsconf_fpga_t acq_parameters;
     bool d_active;
     float d_threshold;
@@ -104,19 +111,27 @@ private:
     float d_test_statistics;
     int32_t d_state;
     uint32_t d_channel;
-    std::shared_ptr<ChannelFsm> d_channel_fsm;
+    std::weak_ptr<ChannelFsm> d_channel_fsm;
     uint32_t d_doppler_step;
+    uint32_t d_doppler_max;
     uint32_t d_fft_size;
     uint32_t d_num_doppler_bins;
     uint64_t d_sample_counter;
     Gnss_Synchro* d_gnss_synchro;
     std::shared_ptr<Fpga_Acquisition> acquisition_fpga;
 
-    float d_downsampling_factor;
+    //float d_downsampling_factor;
+    uint32_t d_downsampling_factor;
     uint32_t d_select_queue_Fpga;
 
     uint32_t d_total_block_exp;
 
+    bool d_make_2_steps;
+    uint32_t d_num_doppler_bins_step2;
+    float d_doppler_step2;
+    float d_doppler_center_step_two;
+    uint32_t d_max_num_acqs;
+
 public:
     ~pcps_acquisition_fpga();
 
@@ -172,11 +187,10 @@ public:
         d_channel = channel;
     }
 
-
     /*!
-      * \brief Set channel fsm associated to this acquisition instance
+     * \brief Set channel fsm associated to this acquisition instance
-      */
+     */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm)
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm)
     {
         d_channel_fsm = channel_fsm;
     }
@@ -197,7 +211,7 @@ public:
      */
     inline void set_doppler_max(uint32_t doppler_max)
     {
-        acq_parameters.doppler_max = doppler_max;
+        d_doppler_max = doppler_max;
         acquisition_fpga->set_doppler_max(doppler_max);
     }
 
@@ -215,11 +229,6 @@ public:
      * \brief This funciton triggers a HW reset of the FPGA PL.
      */
     void reset_acquisition(void);
-
-    /*!
-     * \brief This funciton is only used for the unit tests
-     */
-    void read_fpga_total_scale_factor(uint32_t* total_scale_factor, uint32_t* fw_scale_factor);
 };
 
 #endif /* GNSS_SDR_PCPS_ACQUISITION_FPGA_H_*/

src/algorithms/acquisition/gnuradio_blocks/pcps_assisted_acquisition_cc.h

@@ -138,7 +138,7 @@ private:
     int32_t d_well_count;
     bool d_dump;
     uint32_t d_channel;
-    std::shared_ptr<ChannelFsm> d_channel_fsm;
+    std::weak_ptr<ChannelFsm> d_channel_fsm;
     std::string d_dump_filename;
 
 public:
@@ -199,7 +199,7 @@ public:
     /*!
       * \brief Set channel fsm associated to this acquisition instance
       */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm)
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm)
     {
         d_channel_fsm = channel_fsm;
     }

src/algorithms/acquisition/gnuradio_blocks/pcps_cccwsr_acquisition_cc.h

@@ -117,7 +117,7 @@ private:
     int32_t d_state;
     bool d_dump;
     uint32_t d_channel;
-    std::shared_ptr<ChannelFsm> d_channel_fsm;
+    std::weak_ptr<ChannelFsm> d_channel_fsm;
     std::string d_dump_filename;
 
 public:
@@ -186,7 +186,7 @@ public:
     /*!
       * \brief Set channel fsm associated to this acquisition instance
       */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm)
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm)
     {
         d_channel_fsm = channel_fsm;
     }

src/algorithms/acquisition/gnuradio_blocks/pcps_opencl_acquisition_cc.h

@@ -162,7 +162,7 @@ private:
     cl::CommandQueue* d_cl_queue;
     clFFT_Plan d_cl_fft_plan;
     cl_int d_cl_fft_batch_size;
-    std::shared_ptr<ChannelFsm> d_channel_fsm;
+    std::weak_ptr<ChannelFsm> d_channel_fsm;
     int d_opencl;
 
 public:
@@ -230,7 +230,7 @@ public:
     /*!
       * \brief Set channel fsm associated to this acquisition instance
       */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm)
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm)
     {
         d_channel_fsm = channel_fsm;
     }

src/algorithms/acquisition/gnuradio_blocks/pcps_quicksync_acquisition_cc.h

@@ -151,7 +151,7 @@ private:
     int32_t d_state;
     bool d_dump;
     uint32_t d_channel;
-    std::shared_ptr<ChannelFsm> d_channel_fsm;
+    std::weak_ptr<ChannelFsm> d_channel_fsm;
     std::string d_dump_filename;
 
 public:
@@ -219,7 +219,7 @@ public:
     /*!
       * \brief Set channel fsm associated to this acquisition instance
       */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm)
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm)
     {
         d_channel_fsm = channel_fsm;
     }

src/algorithms/acquisition/gnuradio_blocks/pcps_tong_acquisition_cc.h

@@ -134,7 +134,7 @@ private:
     int32_t d_state;
     bool d_dump;
     uint32_t d_channel;
-    std::shared_ptr<ChannelFsm> d_channel_fsm;
+    std::weak_ptr<ChannelFsm> d_channel_fsm;
     std::string d_dump_filename;
 
 public:
@@ -202,7 +202,7 @@ public:
     /*!
       * \brief Set channel fsm associated to this acquisition instance
       */
-    inline void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm)
+    inline void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm)
     {
         d_channel_fsm = channel_fsm;
     }

src/algorithms/acquisition/libs/fpga_acquisition.cc

@@ -45,23 +45,21 @@
 
 
 // FPGA register parameters
-#define PAGE_SIZE 0x10000                     // default page size for the multicorrelator memory map
+#define PAGE_SIZE 0x10000                    // default page size for the multicorrelator memory map
-#define MAX_PHASE_STEP_RAD 0.999999999534339  // 1 - pow(2,-31);
+#define RESET_ACQUISITION 2                  // command to reset the multicorrelator
-#define RESET_ACQUISITION 2                   // command to reset the multicorrelator
+#define LAUNCH_ACQUISITION 1                 // command to launch the multicorrelator
-#define LAUNCH_ACQUISITION 1                  // command to launch the multicorrelator
+#define TEST_REG_SANITY_CHECK 0x55AA         // value to check the presence of the test register (to detect the hw)
-#define TEST_REG_SANITY_CHECK 0x55AA          // value to check the presence of the test register (to detect the hw)
+#define LOCAL_CODE_CLEAR_MEM 0x10000000      // command to clear the internal memory of the multicorrelator
-#define LOCAL_CODE_CLEAR_MEM 0x10000000       // command to clear the internal memory of the multicorrelator
+#define MEM_LOCAL_CODE_WR_ENABLE 0x0C000000  // command to enable the ENA and WR pins of the internal memory of the multicorrelator
-#define MEM_LOCAL_CODE_WR_ENABLE 0x0C000000   // command to enable the ENA and WR pins of the internal memory of the multicorrelator
+#define POW_2_2 4                            // 2^2 (used for the conversion of floating point numbers to integers)
-#define POW_2_2 4                             // 2^2 (used for the conversion of floating point numbers to integers)
+#define POW_2_31 2147483648                  // 2^31 (used for the conversion of floating point numbers to integers)
-#define POW_2_29 536870912                    // 2^29 (used for the conversion of floating point numbers to integers)
+#define ENABLE_INT_ON_RESET 2                // flag that causes the acquisition to trigger an interrupt when it is reset.
-#define SELECT_LSB 0x00FF                     // value to select the least significant byte
+
-#define SELECT_MSB 0XFF00                     // value to select the most significant byte
+#define SELECT_LSBits 0x0000FFFF         // Select the 10 LSbits out of a 20-bit word
-#define SELECT_16_BITS 0xFFFF                 // value to select 16 bits
+#define SELECT_MSBbits 0xFFFF0000        // Select the 10 MSbits out of a 20-bit word
-#define SHL_8_BITS 256                        // value used to shift a value 8 bits to the left
+#define SELECT_ALL_CODE_BITS 0xFFFFFFFF  // Select a 20 bit word
-#define SELECT_LSBits 0x000003FF              // Select the 10 LSbits out of a 20-bit word
+#define SHL_CODE_BITS 65536              // shift left by 10 bits
-#define SELECT_MSBbits 0x000FFC00             // Select the 10 MSbits out of a 20-bit word
+
-#define SELECT_ALL_CODE_BITS 0x000FFFFF       // Select a 20 bit word
-#define SHL_CODE_BITS 1024                    // shift left by 10 bits
 
 #ifndef TEMP_FAILURE_RETRY
 #define TEMP_FAILURE_RETRY(exp)              \
@@ -84,7 +82,8 @@ Fpga_Acquisition::Fpga_Acquisition(std::string device_name,
     int64_t fs_in,
     uint32_t sampled_ms __attribute__((unused)),
     uint32_t select_queue,
-    lv_16sc_t *all_fft_codes,
+    //lv_16sc_t *all_fft_codes,
+    uint32_t *all_fft_codes,
     uint32_t excludelimit)
 {
     uint32_t vector_length = nsamples_total;
@@ -102,12 +101,10 @@ Fpga_Acquisition::Fpga_Acquisition(std::string device_name,
     d_fd = 0;              // driver descriptor
     d_map_base = nullptr;  // driver memory map
     d_all_fft_codes = all_fft_codes;
-
-    Fpga_Acquisition::reset_acquisition();
     Fpga_Acquisition::open_device();
+    Fpga_Acquisition::reset_acquisition();
     Fpga_Acquisition::fpga_acquisition_test_register();
     Fpga_Acquisition::close_device();
-
     d_PRN = 0;
     DLOG(INFO) << "Acquisition FPGA class created";
 }
@@ -116,12 +113,6 @@ Fpga_Acquisition::Fpga_Acquisition(std::string device_name,
 Fpga_Acquisition::~Fpga_Acquisition() = default;
 
 
-bool Fpga_Acquisition::init()
-{
-    return true;
-}
-
-
 bool Fpga_Acquisition::set_local_code(uint32_t PRN)
 {
     // select the code with the chosen PRN
@@ -132,8 +123,12 @@ bool Fpga_Acquisition::set_local_code(uint32_t PRN)
 
 void Fpga_Acquisition::write_local_code()
 {
-    Fpga_Acquisition::fpga_configure_acquisition_local_code(
+    d_map_base[9] = LOCAL_CODE_CLEAR_MEM;
-        &d_all_fft_codes[d_nsamples_total * (d_PRN - 1)]);
+    // write local code
+    for (uint32_t k = 0; k < d_vector_length; k++)
+        {
+            d_map_base[6] = d_all_fft_codes[d_nsamples_total * (d_PRN - 1) + k];
+        }
 }
 
 
@@ -156,12 +151,6 @@ void Fpga_Acquisition::open_device()
 }
 
 
-bool Fpga_Acquisition::free()
-{
-    return true;
-}
-
-
 void Fpga_Acquisition::fpga_acquisition_test_register()
 {
     // sanity check : check test register
@@ -184,31 +173,11 @@ void Fpga_Acquisition::fpga_acquisition_test_register()
 }
 
 
-void Fpga_Acquisition::fpga_configure_acquisition_local_code(lv_16sc_t fft_local_code[])
-{
-    uint32_t local_code;
-    uint32_t k, tmp, tmp2;
-    uint32_t fft_data;
-
-    d_map_base[9] = LOCAL_CODE_CLEAR_MEM;
-    // write local code
-    for (k = 0; k < d_vector_length; k++)
-        {
-            tmp = fft_local_code[k].real();
-            tmp2 = fft_local_code[k].imag();
-
-            local_code = (tmp & SELECT_LSBits) | ((tmp2 * SHL_CODE_BITS) & SELECT_MSBbits);  // put together the real part and the imaginary part
-            fft_data = local_code & SELECT_ALL_CODE_BITS;
-            d_map_base[6] = fft_data;
-        }
-}
-
-
 void Fpga_Acquisition::run_acquisition(void)
 {
     // enable interrupts
     int32_t reenable = 1;
-    int32_t disable_int = 0;
+    //int32_t disable_int = 0;
     ssize_t nbytes = TEMP_FAILURE_RETRY(write(d_fd, reinterpret_cast<void *>(&reenable), sizeof(int32_t)));
     if (nbytes != sizeof(int32_t))
         {
@@ -228,11 +197,11 @@ void Fpga_Acquisition::run_acquisition(void)
             std::cout << "acquisition module Interrupt number " << irq_count << std::endl;
         }
 
-    nbytes = TEMP_FAILURE_RETRY(write(d_fd, reinterpret_cast<void *>(&disable_int), sizeof(int32_t)));
+    //    nbytes = TEMP_FAILURE_RETRY(write(d_fd, reinterpret_cast<void *>(&disable_int), sizeof(int32_t)));
-    if (nbytes != sizeof(int32_t))
+    //    if (nbytes != sizeof(int32_t))
-        {
+    //        {
-            std::cerr << "Error disabling interruptions in the FPGA." << std::endl;
+    //            std::cerr << "Error disabling interruptions in the FPGA." << std::endl;
-        }
+    //        }
 }
 
 
@@ -241,47 +210,30 @@ void Fpga_Acquisition::set_block_exp(uint32_t total_block_exp)
     d_map_base[11] = total_block_exp;
 }
 
-
+void Fpga_Acquisition::set_doppler_sweep(uint32_t num_sweeps, uint32_t doppler_step, int32_t doppler_min)
-void Fpga_Acquisition::set_doppler_sweep(uint32_t num_sweeps)
 {
     float phase_step_rad_real;
-    float phase_step_rad_int_temp;
     int32_t phase_step_rad_int;
-    auto doppler = static_cast<int32_t>(-d_doppler_max);
+
-    float phase_step_rad = GPS_TWO_PI * (doppler) / static_cast<float>(d_fs_in);
     // The doppler step can never be outside the range -pi to +pi, otherwise there would be aliasing
     // The FPGA expects phase_step_rad between -1 (-pi) to +1 (+pi)
-    // The FPGA also expects the phase to be negative since it produces cos(x) -j*sin(x)
+    phase_step_rad_real = 2.0 * (doppler_min) / static_cast<float>(d_fs_in);
-    phase_step_rad_real = phase_step_rad / (GPS_TWO_PI / 2);
+    phase_step_rad_int = static_cast<int32_t>(phase_step_rad_real * (POW_2_31));
-
-    // avoid saturation of the fixed point representation in the fpga
-    // (only the positive value can saturate due to the 2's complement representation)
-    if (phase_step_rad_real >= 1.0)
-        {
-            phase_step_rad_real = MAX_PHASE_STEP_RAD;
-        }
-    phase_step_rad_int_temp = phase_step_rad_real * POW_2_2;                          // * 2^2
-    phase_step_rad_int = static_cast<int32_t>(phase_step_rad_int_temp * (POW_2_29));  // * 2^29 (in total it makes x2^31 in two steps to avoid the warnings
     d_map_base[3] = phase_step_rad_int;
 
     // repeat the calculation with the doppler step
-    doppler = static_cast<int32_t>(d_doppler_step);
+    phase_step_rad_real = 2.0 * (doppler_step) / static_cast<float>(d_fs_in);
-    phase_step_rad = GPS_TWO_PI * (doppler) / static_cast<float>(d_fs_in);
+    phase_step_rad_int = static_cast<int32_t>(phase_step_rad_real * (POW_2_31));  // * 2^29 (in total it makes x2^31 in two steps to avoid the warnings
-    phase_step_rad_real = phase_step_rad / (GPS_TWO_PI / 2);
-    if (phase_step_rad_real >= 1.0)
-        {
-            phase_step_rad_real = MAX_PHASE_STEP_RAD;
-        }
-    phase_step_rad_int_temp = phase_step_rad_real * POW_2_2;                          // * 2^2
-    phase_step_rad_int = static_cast<int32_t>(phase_step_rad_int_temp * (POW_2_29));  // * 2^29 (in total it makes x2^31 in two steps to avoid the warnings
     d_map_base[4] = phase_step_rad_int;
+
+    // write number of doppler sweeps
     d_map_base[5] = num_sweeps;
 }
 
 
 void Fpga_Acquisition::configure_acquisition()
 {
-    Fpga_Acquisition::open_device();
+    //Fpga_Acquisition::open_device();
 
     d_map_base[0] = d_select_queue;
     d_map_base[1] = d_vector_length;
@@ -291,30 +243,6 @@ void Fpga_Acquisition::configure_acquisition()
 }
 
 
-void Fpga_Acquisition::set_phase_step(uint32_t doppler_index)
-{
-    float phase_step_rad_real;
-    float phase_step_rad_int_temp;
-    int32_t phase_step_rad_int;
-    int32_t doppler = -static_cast<int32_t>(d_doppler_max) + d_doppler_step * doppler_index;
-    float phase_step_rad = GPS_TWO_PI * (doppler) / static_cast<float>(d_fs_in);
-    // The doppler step can never be outside the range -pi to +pi, otherwise there would be aliasing
-    // The FPGA expects phase_step_rad between -1 (-pi) to +1 (+pi)
-    // The FPGA also expects the phase to be negative since it produces cos(x) -j*sin(x)
-    // while the gnss-sdr software (volk_gnsssdr_s32f_sincos_32fc) generates cos(x) + j*sin(x)
-    phase_step_rad_real = phase_step_rad / (GPS_TWO_PI / 2);
-    // avoid saturation of the fixed point representation in the fpga
-    // (only the positive value can saturate due to the 2's complement representation)
-    if (phase_step_rad_real >= 1.0)
-        {
-            phase_step_rad_real = MAX_PHASE_STEP_RAD;
-        }
-    phase_step_rad_int_temp = phase_step_rad_real * POW_2_2;                          // * 2^2
-    phase_step_rad_int = static_cast<int32_t>(phase_step_rad_int_temp * (POW_2_29));  // * 2^29 (in total it makes x2^31 in two steps to avoid the warnings
-    d_map_base[3] = phase_step_rad_int;
-}
-
-
 void Fpga_Acquisition::read_acquisition_results(uint32_t *max_index,
     float *firstpeak, float *secondpeak, uint64_t *initial_sample, float *power_sum, uint32_t *doppler_index, uint32_t *total_blk_exp)
 {
@@ -323,35 +251,31 @@ void Fpga_Acquisition::read_acquisition_results(uint32_t *max_index,
     uint64_t readval_long = 0;
     uint64_t readval_long_shifted = 0;
 
-    readval = d_map_base[1];
+    readval = d_map_base[1];  // read sample counter (LSW)
     initial_sample_tmp = readval;
 
-    readval_long = d_map_base[2];
+    readval_long = d_map_base[2];               // read sample counter (MSW)
     readval_long_shifted = readval_long << 32;  // 2^32
 
     initial_sample_tmp = initial_sample_tmp + readval_long_shifted;  // 2^32
     *initial_sample = initial_sample_tmp;
 
-    readval = d_map_base[3];
+    readval = d_map_base[3];  // read first peak value
     *firstpeak = static_cast<float>(readval);
 
-    readval = d_map_base[4];
+    readval = d_map_base[4];  // read second peak value
     *secondpeak = static_cast<float>(readval);
 
-    readval = d_map_base[5];
+    readval = d_map_base[5];  // read max index position
     *max_index = readval;
 
-    *power_sum = 0;
+    *power_sum = 0;  // power sum is not used
-
-    readval = d_map_base[8];
-    *total_blk_exp = readval;
 
     readval = d_map_base[7];  // read doppler index -- this read releases the interrupt line
     *doppler_index = readval;
 
-    readval = d_map_base[15];  // read dummy
+    readval = d_map_base[8];  // read FFT block exponent
-
+    *total_blk_exp = readval;
-    Fpga_Acquisition::close_device();
 }
 
 
@@ -380,9 +304,9 @@ void Fpga_Acquisition::close_device()
 
 void Fpga_Acquisition::reset_acquisition(void)
 {
-    Fpga_Acquisition::open_device();
+    d_map_base[8] = RESET_ACQUISITION;     // writing a 2 to d_map_base[8] resets the acquisition. This causes a reset of all
-    d_map_base[8] = RESET_ACQUISITION;  // writing a 2 to d_map_base[8] resets the multicorrelator
+                                           // the FPGA HW modules including the multicorrelators
-    Fpga_Acquisition::close_device();
+    d_map_base[14] = ENABLE_INT_ON_RESET;  // enable int on reset
 }
 
 
@@ -392,8 +316,7 @@ void Fpga_Acquisition::read_fpga_total_scale_factor(uint32_t *total_scale_factor
     uint32_t readval = 0;
     readval = d_map_base[8];
     *total_scale_factor = readval;
-
+    // only the total scale factor is used for the tests (fw scale factor to be removed)
-    //readval = d_map_base[8];
     *fw_scale_factor = 0;
 }
 

src/algorithms/acquisition/libs/fpga_acquisition.h

@@ -53,16 +53,14 @@ public:
         int64_t fs_in,
         uint32_t sampled_ms,
         uint32_t select_queue,
-        lv_16sc_t *all_fft_codes,
+        uint32_t *all_fft_codes,
         uint32_t excludelimit);
 
     ~Fpga_Acquisition();
-    bool init();
     bool set_local_code(uint32_t PRN);
-    bool free();
+    void set_doppler_sweep(uint32_t num_sweeps, uint32_t doppler_step, int32_t doppler_min);
-    void set_doppler_sweep(uint32_t num_sweeps);
     void run_acquisition(void);
-    void set_phase_step(uint32_t doppler_index);
+
     void read_acquisition_results(uint32_t *max_index, float *firstpeak, float *secondpeak, uint64_t *initial_sample, float *power_sum, uint32_t *doppler_index, uint32_t *total_blk_exp);
 
     void block_samples();
@@ -110,7 +108,7 @@ private:
     // data related to the hardware module and the driver
     int32_t d_fd;                   // driver descriptor
     volatile uint32_t *d_map_base;  // driver memory map
-    lv_16sc_t *d_all_fft_codes;     // memory that contains all the code ffts
+    uint32_t *d_all_fft_codes;      // memory that contains all the code ffts
     uint32_t d_vector_length;       // number of samples incluing padding and number of ms
     uint32_t d_excludelimit;
     uint32_t d_nsamples_total;  // number of samples including padding
@@ -122,7 +120,6 @@ private:
     uint32_t d_PRN;             // PRN
     // FPGA private functions
     void fpga_acquisition_test_register(void);
-    void fpga_configure_acquisition_local_code(lv_16sc_t fft_local_code[]);
     void read_result_valid(uint32_t *result_valid);
 };
 

src/algorithms/channel/adapters/channel.cc

@@ -218,7 +218,6 @@ void Channel::set_signal(const Gnss_Signal& gnss_signal)
     acq_->set_local_code();
     if (flag_enable_fpga)
         {
-            //set again the gnss_synchro pointer to trigger the preloading of the current PRN code to the FPGA fabric
             trk_->set_gnss_synchro(&gnss_synchro_);
         }
     nav_->set_satellite(gnss_signal_.get_satellite());

src/algorithms/libs/volk_gnsssdr_module/volk_gnsssdr/cmake/Modules/VolkPython.cmake

@@ -20,53 +20,6 @@ if(DEFINED __INCLUDED_VOLK_PYTHON_CMAKE)
 endif()
 set(__INCLUDED_VOLK_PYTHON_CMAKE TRUE)
 
-########################################################################
-# Setup the python interpreter:
-# This allows the user to specify a specific interpreter,
-# or finds the interpreter via the built-in cmake module.
-########################################################################
-set(VOLK_PYTHON_MIN_VERSION "2.7")
-set(VOLK_PYTHON3_MIN_VERSION "3.4")
-
-if(CMAKE_VERSION VERSION_LESS 3.12)
-    if(PYTHON_EXECUTABLE)
-        message(STATUS "User set python executable ${PYTHON_EXECUTABLE}")
-        find_package(PythonInterp ${VOLK_PYTHON_MIN_VERSION} REQUIRED)
-    else()
-        message(STATUS "PYTHON_EXECUTABLE not set - using default python2")
-        message(STATUS "Use -DPYTHON_EXECUTABLE=/path/to/python3 to build for python3.")
-        find_package(PythonInterp ${VOLK_PYTHON_MIN_VERSION})
-        if(NOT PYTHONINTERP_FOUND)
-            message(STATUS "python2 not found - using python3")
-            find_package(PythonInterp ${VOLK_PYTHON3_MIN_VERSION} REQUIRED)
-        endif()
-    endif()
-else()
-    if(PYTHON_EXECUTABLE)
-        message(STATUS "User set python executable ${PYTHON_EXECUTABLE}")
-        find_package(PythonInterp ${VOLK_PYTHON_MIN_VERSION} REQUIRED)
-    else()
-        find_package(Python3 COMPONENTS Interpreter)
-        if(Python3_FOUND)
-            set(PYTHON_EXECUTABLE ${Python3_EXECUTABLE})
-            set(PYTHON_VERSION_MAJOR ${Python3_VERSION_MAJOR})
-        endif()
-        if(NOT Python3_FOUND OR NOT MAKO_FOUND OR NOT SIX_FOUND)
-            find_package(Python2 COMPONENTS Interpreter)
-            if(Python2_FOUND)
-                set(PYTHON_EXECUTABLE ${Python2_EXECUTABLE})
-                set(PYTHON_VERSION_MAJOR ${Python2_VERSION_MAJOR})
-            endif()
-        endif()
-    endif()
-endif()
-
-if(${PYTHON_VERSION_MAJOR} VERSION_EQUAL 3)
-    set(PYTHON3 TRUE)
-endif()
-
-
-
 ########################################################################
 # Check for the existence of a python module:
 # - desc a string description of the check
@@ -102,6 +55,61 @@ except: pass
     "${have}")
 endmacro()
 
+
+########################################################################
+# Setup the python interpreter:
+# This allows the user to specify a specific interpreter,
+# or finds the interpreter via the built-in cmake module.
+########################################################################
+set(VOLK_PYTHON_MIN_VERSION "2.7")
+set(VOLK_PYTHON3_MIN_VERSION "3.4")
+
+if(CMAKE_VERSION VERSION_LESS 3.12)
+    if(PYTHON_EXECUTABLE)
+        message(STATUS "User set python executable ${PYTHON_EXECUTABLE}")
+        find_package(PythonInterp ${VOLK_PYTHON_MIN_VERSION} REQUIRED)
+    else()
+        message(STATUS "PYTHON_EXECUTABLE not set - using default python2")
+        message(STATUS "Use -DPYTHON_EXECUTABLE=/path/to/python3 to build for python3.")
+        find_package(PythonInterp ${VOLK_PYTHON_MIN_VERSION})
+        if(NOT PYTHONINTERP_FOUND)
+            message(STATUS "python2 not found - using python3")
+            find_package(PythonInterp ${VOLK_PYTHON3_MIN_VERSION} REQUIRED)
+        endif()
+    endif()
+else()
+    if(PYTHON_EXECUTABLE)
+        message(STATUS "User set python executable ${PYTHON_EXECUTABLE}")
+        find_package(PythonInterp ${VOLK_PYTHON_MIN_VERSION} REQUIRED)
+    else()
+        find_package(Python3 COMPONENTS Interpreter)
+        if(Python3_FOUND)
+            set(PYTHON_EXECUTABLE ${Python3_EXECUTABLE})
+            set(PYTHON_VERSION_MAJOR ${Python3_VERSION_MAJOR})
+            volk_python_check_module("mako >= 0.4.2" mako "mako.__version__ >= '0.4.2'" MAKO_FOUND)
+            volk_python_check_module("six - python 2 and 3 compatibility library" six "True" SIX_FOUND)
+        endif()
+        if(NOT Python3_FOUND OR NOT MAKO_FOUND OR NOT SIX_FOUND)
+            find_package(Python2 COMPONENTS Interpreter)
+            if(Python2_FOUND)
+                set(PYTHON_EXECUTABLE ${Python2_EXECUTABLE})
+                set(PYTHON_VERSION_MAJOR ${Python2_VERSION_MAJOR})
+                volk_python_check_module("mako >= 0.4.2" mako "mako.__version__ >= '0.4.2'" MAKO_FOUND)
+                volk_python_check_module("six - python 2 and 3 compatibility library" six "True" SIX_FOUND)
+            endif()
+            if(NOT MAKO_FOUND OR NOT SIX_FOUND)
+                unset(PYTHON_EXECUTABLE)
+                find_package(PythonInterp ${VOLK_PYTHON_MIN_VERSION})
+            endif()
+        endif()
+    endif()
+endif()
+
+if(${PYTHON_VERSION_MAJOR} VERSION_EQUAL 3)
+    set(PYTHON3 TRUE)
+endif()
+
+
 ########################################################################
 # Sets the python installation directory VOLK_PYTHON_DIR
 ########################################################################

src/algorithms/observables/gnuradio_blocks/hybrid_observables_gs.cc

@@ -114,7 +114,7 @@ hybrid_observables_gs::hybrid_observables_gs(uint32_t nchannels_in,
                 }
         }
     T_rx_TOW_ms = 0U;
-    T_rx_TOW_offset_ms = 0U;
+    T_rx_step_ms = 20;  //read from config at the adapter GNSS-SDR.observable_interval_ms!!
     T_rx_TOW_set = false;
 
     // rework
@@ -443,38 +443,39 @@ void hybrid_observables_gs::update_TOW(const std::vector<Gnss_Synchro> &data)
     //2. If the TOW is set, it must be incremented by the desired receiver time step.
     //   the time step must match the observables timer block (connected to the las input channel)
     std::vector<Gnss_Synchro>::const_iterator it;
-    //    if (!T_rx_TOW_set)
+    if (!T_rx_TOW_set)
-    //        {
-    //uint32_t TOW_ref = std::numeric_limits<uint32_t>::max();
-    uint32_t TOW_ref = 0U;
-    for (it = data.cbegin(); it != data.cend(); it++)
         {
-            if (it->Flag_valid_word)
+            //uint32_t TOW_ref = std::numeric_limits<uint32_t>::max();
+            uint32_t TOW_ref = 0U;
+            for (it = data.cbegin(); it != data.cend(); it++)
                 {
-                    if (it->TOW_at_current_symbol_ms > TOW_ref)
+                    if (it->Flag_valid_word)
                         {
-                            TOW_ref = it->TOW_at_current_symbol_ms;
+                            if (it->TOW_at_current_symbol_ms > TOW_ref)
-                            T_rx_TOW_set = true;
+                                {
+                                    TOW_ref = it->TOW_at_current_symbol_ms;
+                                    T_rx_TOW_set = true;
+                                }
                         }
                 }
+            T_rx_TOW_ms = TOW_ref - (TOW_ref % 20);
+        }
+    else
+        {
+            T_rx_TOW_ms += T_rx_step_ms;  //the tow time step increment must match the ref time channel step
+            //todo: check what happens during the week rollover
+            if (T_rx_TOW_ms >= 604800000)
+                {
+                    T_rx_TOW_ms = T_rx_TOW_ms % 604800000;
+                }
         }
-    T_rx_TOW_ms = TOW_ref;
-    //}
-    //    else
-    //        {
-    //            T_rx_TOW_ms += T_rx_step_ms;
-    //            //todo: check what happens during the week rollover
-    //            if (T_rx_TOW_ms >= 604800000)
-    //                {
-    //                    T_rx_TOW_ms = T_rx_TOW_ms % 604800000;
-    //                }
-    //        }
-    //    std::cout << "T_rx_TOW_ms: " << T_rx_TOW_ms << std::endl;
 }
 
 
 void hybrid_observables_gs::compute_pranges(std::vector<Gnss_Synchro> &data)
 {
+    //    std::cout.precision(17);
+    //    std::cout << " T_rx_TOW_ms: " << static_cast<double>(T_rx_TOW_ms) << std::endl;
     std::vector<Gnss_Synchro>::iterator it;
     for (it = data.begin(); it != data.end(); it++)
         {
@@ -486,13 +487,21 @@ void hybrid_observables_gs::compute_pranges(std::vector<Gnss_Synchro> &data)
                     it->Pseudorange_m = traveltime_s * SPEED_OF_LIGHT;
                     it->Flag_valid_pseudorange = true;
                     // debug code
-                    // std::cout.precision(17);
+                    //
-                    // std::cout << "[" << it->Channel_ID << "] interp_TOW_ms: " << it->interp_TOW_ms << std::endl;
+                    //                    std::cout << "[" << it->Channel_ID << "] interp_TOW_ms: " << it->interp_TOW_ms << std::endl;
-                    // std::cout << "[" << it->Channel_ID << "] Diff T_rx_TOW_ms - interp_TOW_ms: " << static_cast<double>(T_rx_TOW_ms) - it->interp_TOW_ms << std::endl;
+                    //                    std::cout << "[" << it->Channel_ID << "] Diff T_rx_TOW_ms - interp_TOW_ms: " << static_cast<double>(T_rx_TOW_ms) - it->interp_TOW_ms << std::endl;
-                    // std::cout << "[" << it->Channel_ID << "] Pseudorange_m: " << it->Pseudorange_m << std::endl;
                 }
         }
-    // usleep(1000);
+
+    //    for (it = data.begin(); it != data.end(); it++)
+    //        {
+    //            if (it->Flag_valid_word)
+    //                {
+    //                    std::cout << "[" << it->Channel_ID << "] Pseudorange_m: " << it->Pseudorange_m << std::endl;
+    //                }
+    //        }
+    //    std::cout << std::endl;
+    //    usleep(1000);
 }
 
 
@@ -548,7 +557,7 @@ int hybrid_observables_gs::general_work(int noutput_items __attribute__((unused)
             for (uint32_t n = 0; n < d_nchannels_out; n++)
                 {
                     Gnss_Synchro interpolated_gnss_synchro{};
-                    if (!interp_trk_obs(interpolated_gnss_synchro, n, d_Rx_clock_buffer.front() + T_rx_TOW_offset_ms * T_rx_clock_step_samples))
+                    if (!interp_trk_obs(interpolated_gnss_synchro, n, d_Rx_clock_buffer.front()))
                         {
                             // Produce an empty observation
                             interpolated_gnss_synchro = Gnss_Synchro();
@@ -564,49 +573,10 @@ int hybrid_observables_gs::general_work(int noutput_items __attribute__((unused)
                         }
                     epoch_data.push_back(interpolated_gnss_synchro);
                 }
-            if (n_valid > 0)
-                {
-                    update_TOW(epoch_data);
-                    int tow_inc_loop_count = 0;
-                    while (T_rx_TOW_ms % 20 != 0 and tow_inc_loop_count < 20)
-                        {
-                            tow_inc_loop_count++;
-                            T_rx_TOW_offset_ms++;
-                            T_rx_TOW_offset_ms = T_rx_TOW_offset_ms % 20;
-                            //check if effectively the receiver TOW is now multiple of 20 ms
-                            n_valid = 0;
-                            epoch_data.clear();
-                            for (uint32_t n = 0; n < d_nchannels_out; n++)
-                                {
-                                    Gnss_Synchro interpolated_gnss_synchro{};
-                                    if (!interp_trk_obs(interpolated_gnss_synchro, n, d_Rx_clock_buffer.front() + T_rx_TOW_offset_ms * T_rx_clock_step_samples))
-                                        {
-                                            // Produce an empty observation
-                                            interpolated_gnss_synchro = Gnss_Synchro();
-                                            interpolated_gnss_synchro.Flag_valid_pseudorange = false;
-                                            interpolated_gnss_synchro.Flag_valid_word = false;
-                                            interpolated_gnss_synchro.Flag_valid_acquisition = false;
-                                            interpolated_gnss_synchro.fs = 0;
-                                            interpolated_gnss_synchro.Channel_ID = n;
-                                        }
-                                    else
-                                        {
-                                            n_valid++;
-                                        }
-                                    epoch_data.push_back(interpolated_gnss_synchro);
-                                }
-                            update_TOW(epoch_data);
-                            // debug code:
-                            // if (T_rx_TOW_ms % 20 != 0)
-                            //     {
-                            //         std::cout << "Warning: RX TOW is not multiple of 20 ms\n";
-                            //     }
-                            // std::cout << "T_rx_TOW_ms=" << T_rx_TOW_ms << " T_rx_TOW_offset_ms=" << T_rx_TOW_offset_ms << " ->" << T_rx_TOW_ms % 20 << std::endl;
-                        }
-                }
 
             if (n_valid > 0)
                 {
+                    update_TOW(epoch_data);
                     compute_pranges(epoch_data);
                 }
 

src/algorithms/observables/gnuradio_blocks/hybrid_observables_gs.h

@@ -83,7 +83,7 @@ private:
     //rx time follow GPST
     bool T_rx_TOW_set;
     uint32_t T_rx_TOW_ms;
-    uint32_t T_rx_TOW_offset_ms;
+    uint32_t T_rx_step_ms;
     bool d_dump;
     bool d_dump_mat;
     uint32_t d_nchannels_in;

src/algorithms/signal_source/adapters/ad9361_fpga_signal_source.cc

@@ -53,10 +53,10 @@ Ad9361FpgaSignalSource::Ad9361FpgaSignalSource(ConfigurationInterface* configura
     std::string default_item_type = "gr_complex";
     std::string default_dump_file = "./data/signal_source.dat";
     freq_ = configuration->property(role + ".freq", GPS_L1_FREQ_HZ);
-    sample_rate_ = configuration->property(role + ".sampling_frequency", 2600000);
+    sample_rate_ = configuration->property(role + ".sampling_frequency", 12500000);
-    bandwidth_ = configuration->property(role + ".bandwidth", 2000000);
+    bandwidth_ = configuration->property(role + ".bandwidth", 12500000);
     rx1_en_ = configuration->property(role + ".rx1_enable", true);
-    rx2_en_ = configuration->property(role + ".rx2_enable", false);
+    rx2_en_ = configuration->property(role + ".rx2_enable", true);
     buffer_size_ = configuration->property(role + ".buffer_size", 0xA0000);
     quadrature_ = configuration->property(role + ".quadrature", true);
     rf_dc_ = configuration->property(role + ".rf_dc", true);

src/algorithms/signal_source/adapters/labsat_signal_source.cc

@@ -40,21 +40,20 @@ LabsatSignalSource::LabsatSignalSource(ConfigurationInterface* configuration,
     const std::string& role, unsigned int in_stream, unsigned int out_stream, gr::msg_queue::sptr queue) : role_(role), in_stream_(in_stream), out_stream_(out_stream), queue_(std::move(queue))
 {
     std::string default_item_type = "gr_complex";
-    std::string default_dump_file = "./data/source.bin";
+    std::string default_dump_file = "./labsat_output.dat";
     item_type_ = configuration->property(role + ".item_type", default_item_type);
     dump_ = configuration->property(role + ".dump", false);
     dump_filename_ = configuration->property(role + ".dump_filename", default_dump_file);
 
     int channel_selector = configuration->property(role + ".selected_channel", 1);
-    std::string default_filename = "./example_capture.LS3";
 
-    samples_ = configuration->property(role + ".samples", 0);
+    std::string default_filename = "./example_capture.LS3";
     filename_ = configuration->property(role + ".filename", default_filename);
 
     if (item_type_ == "gr_complex")
         {
             item_size_ = sizeof(gr_complex);
-            labsat23_source_ = labsat23_make_source(filename_.c_str(), channel_selector);
+            labsat23_source_ = labsat23_make_source_sptr(filename_.c_str(), channel_selector, queue_);
             DLOG(INFO) << "Item size " << item_size_;
             DLOG(INFO) << "labsat23_source_(" << labsat23_source_->unique_id() << ")";
         }

src/algorithms/signal_source/adapters/labsat_signal_source.h

@@ -81,7 +81,6 @@ private:
     unsigned int out_stream_;
     std::string item_type_;
     size_t item_size_;
-    uint64_t samples_;
     std::string filename_;
     bool dump_;
     std::string dump_filename_;

src/algorithms/signal_source/gnuradio_blocks/CMakeLists.txt

@@ -64,6 +64,7 @@ target_link_libraries(signal_source_gr_blocks
         Gnuradio::runtime
         signal_source_libs
     PRIVATE
+        core_receiver
         Gflags::gflags
         Glog::glog
 )

src/algorithms/signal_source/gnuradio_blocks/labsat23_source.cc

@@ -30,30 +30,25 @@
 
 
 #include "labsat23_source.h"
+#include "control_message_factory.h"
 #include <gnuradio/io_signature.h>
 #include <exception>
 #include <iostream>
 #include <sstream>
 
 
-labsat23_source_sptr labsat23_make_source(const char *signal_file_basename, int channel_selector)
+labsat23_source_sptr labsat23_make_source_sptr(const char *signal_file_basename, int channel_selector, gr::msg_queue::sptr queue)
 {
-    return labsat23_source_sptr(new labsat23_source(signal_file_basename, channel_selector));
+    return labsat23_source_sptr(new labsat23_source(signal_file_basename, channel_selector, queue));
-}
-
-
-std::string labsat23_source::generate_filename()
-{
-    std::ostringstream ss;
-    ss << std::setw(4) << std::setfill('0') << d_current_file_number;
-    return d_signal_file_basename + "_" + ss.str() + ".LS3";
 }
 
 
 labsat23_source::labsat23_source(const char *signal_file_basename,
-    int channel_selector) : gr::block("labsat23_source",
+    int channel_selector,
-                                gr::io_signature::make(0, 0, 0),
+    gr::msg_queue::sptr queue) : gr::block("labsat23_source",
-                                gr::io_signature::make(1, 1, sizeof(gr_complex)))
+                                     gr::io_signature::make(0, 0, 0),
+                                     gr::io_signature::make(1, 1, sizeof(gr_complex))),
+                                 d_queue(queue)
 {
     if (channel_selector < 1 or channel_selector > 2)
         {
@@ -108,6 +103,25 @@ labsat23_source::~labsat23_source()
 }
 
 
+std::string labsat23_source::generate_filename()
+{
+    if (d_signal_file_basename.substr(d_signal_file_basename.length() - 4, 4) == ".ls2" or d_signal_file_basename.substr(d_signal_file_basename.length() - 4, 4) == ".LS2")
+        {
+            if (d_current_file_number == 0)
+                {
+                    return d_signal_file_basename;
+                }
+            else
+                {
+                    return std::string("donotexist");  // just to stop processing
+                }
+        }
+    std::ostringstream ss;
+    ss << std::setw(4) << std::setfill('0') << d_current_file_number;
+    return d_signal_file_basename + "_" + ss.str() + ".LS3";
+}
+
+
 int labsat23_source::getBit(uint8_t byte, int position)
 {
     return (byte >> position) & 0x01;
@@ -120,7 +134,7 @@ void labsat23_source::decode_samples_one_channel(int16_t input_short, gr_complex
     switch (type)
         {
         case 2:
-            //two bits per sample, 8 samples per int16
+            // two bits per sample, 8 samples per int16
             for (int i = 0; i < 8; i++)
                 {
                     out[i] = gr_complex(static_cast<float>(bs[15 - (2 * i)]),
@@ -129,45 +143,45 @@ void labsat23_source::decode_samples_one_channel(int16_t input_short, gr_complex
                 }
             break;
         case 4:
-            //four bits per sample, 4 samples per int16
+            //  bits per sample, 4 samples per int16
             for (int i = 0; i < 4; i++)
                 {
                     out[i] = gr_complex(0.0, 0.0);
-                    //In-Phase
+                    // In-Phase
                     if (bs[15 - 4 * i])
                         {
-                            if (bs[13 - 4 * i])  //11
+                            if (bs[13 - 4 * i])  // 11
                                 {
                                     out[i] += gr_complex(-1, 0);
                                 }
-                            else  //10
+                            else  // 10
                                 {
                                     out[i] += gr_complex(-2, 0);
                                 }
                         }
                     else
                         {
-                            if (bs[13 - 4 * i])  //01
+                            if (bs[13 - 4 * i])  // 01
                                 {
                                     out[i] += gr_complex(1, 0);
                                 }
                         }
 
-                    //Quadrature
+                    // Quadrature
                     if (bs[14 - 4 * i])
                         {
-                            if (bs[12 - 4 * i])  //11
+                            if (bs[12 - 4 * i])  // 11
                                 {
                                     out[i] += gr_complex(0, -1);
                                 }
-                            else  //10
+                            else  // 10
                                 {
                                     out[i] += gr_complex(0, -2);
                                 }
                         }
                     else
                         {
-                            if (bs[12 - 4 * i])  //01
+                            if (bs[12 - 4 * i])  // 01
                                 {
                                     out[i] += gr_complex(0, 1);
                                 }
@@ -192,8 +206,8 @@ int labsat23_source::general_work(int noutput_items,
                 {
                     char memblock[1024];
                     binary_input_file->read(memblock, 1024);
-                    //parse Labsat header
+                    // parse Labsat header
-                    //check preamble
+                    // check preamble
                     int byte_counter = 0;
                     bool preamble_ok = true;
                     for (int i = 0; i < 8; i++)
@@ -388,7 +402,6 @@ int labsat23_source::general_work(int noutput_items,
             return -1;
         }
 
-
     // ready to start reading samples
     switch (d_bits_per_sample)
         {
@@ -419,8 +432,10 @@ int labsat23_source::general_work(int noutput_items,
                                     }
 
                                 // trigger the read of the next file in the sequence
-                                std::cout << "End of current file, reading the next Labsat file in sequence: " << generate_filename() << std::endl;
+                                if (d_labsat_version == 3)
-
+                                    {
+                                        std::cout << "End of current file, reading the next Labsat file in sequence: " << generate_filename() << std::endl;
+                                    }
                                 d_current_file_number++;
                                 binary_input_file->close();
                                 binary_input_file->open(generate_filename().c_str(), std::ios::in | std::ios::binary);
@@ -430,7 +445,17 @@ int labsat23_source::general_work(int noutput_items,
                                     }
                                 else
                                     {
-                                        std::cout << "Last file reached, LabSat source stop" << std::endl;
+                                        if (d_labsat_version == 3)
+                                            {
+                                                std::cout << "Last file reached, LabSat source stop" << std::endl;
+                                            }
+                                        else
+                                            {
+                                                std::cout << "End of file reached, LabSat source stop" << std::endl;
+                                            }
+                                        auto *cmf = new ControlMessageFactory();
+                                        d_queue->handle(cmf->GetQueueMessage(200, 0));
+                                        delete cmf;
                                         return -1;
                                     }
                             }
@@ -468,8 +493,10 @@ int labsat23_source::general_work(int noutput_items,
                                     }
 
                                 // trigger the read of the next file in the sequence
-                                std::cout << "End of current file, reading the next Labsat file in sequence: " << generate_filename() << std::endl;
+                                if (d_labsat_version == 3)
-
+                                    {
+                                        std::cout << "End of current file, reading the next Labsat file in sequence: " << generate_filename() << std::endl;
+                                    }
                                 d_current_file_number++;
                                 binary_input_file->close();
                                 binary_input_file->open(generate_filename().c_str(), std::ios::in | std::ios::binary);
@@ -479,7 +506,17 @@ int labsat23_source::general_work(int noutput_items,
                                     }
                                 else
                                     {
-                                        std::cout << "Last file reached, LabSat source stop" << std::endl;
+                                        if (d_labsat_version == 3)
+                                            {
+                                                std::cout << "Last file reached, LabSat source stop" << std::endl;
+                                            }
+                                        else
+                                            {
+                                                std::cout << "End of file reached, LabSat source stop" << std::endl;
+                                            }
+                                        auto *cmf = new ControlMessageFactory();
+                                        d_queue->handle(cmf->GetQueueMessage(200, 0));
+                                        delete cmf;
                                         return -1;
                                     }
                             }

src/algorithms/signal_source/gnuradio_blocks/labsat23_source.h

@@ -32,6 +32,7 @@
 #define GNSS_SDR_LABSAT23_SOURCE_H
 
 #include <gnuradio/block.h>
+#include <gnuradio/msg_queue.h>  // for msg_queue, msg_queue::sptr
 #include <cstdint>
 #include <fstream>
 #include <string>
@@ -41,7 +42,7 @@ class labsat23_source;
 
 using labsat23_source_sptr = boost::shared_ptr<labsat23_source>;
 
-labsat23_source_sptr labsat23_make_source(const char *signal_file_basename, int channel_selector);
+labsat23_source_sptr labsat23_make_source_sptr(const char *signal_file_basename, int channel_selector, gr::msg_queue::sptr queue);
 
 /*!
  * \brief This class implements conversion between Labsat2 and 3 format byte packet samples to gr_complex
@@ -49,7 +50,8 @@ labsat23_source_sptr labsat23_make_source(const char *signal_file_basename, int
 class labsat23_source : public gr::block
 {
 private:
-    friend labsat23_source_sptr labsat23_make_source_sptr(const char *signal_file_basename, int channel_selector);
+    friend labsat23_source_sptr labsat23_make_source_sptr(const char *signal_file_basename, int channel_selector, gr::msg_queue::sptr queue);
+    labsat23_source(const char *signal_file_basename, int channel_selector, gr::msg_queue::sptr queue);
     std::string generate_filename();
     void decode_samples_one_channel(int16_t input_short, gr_complex *out, int type);
     int getBit(uint8_t byte, int position);
@@ -62,9 +64,9 @@ private:
     std::ifstream *binary_input_file;
     uint8_t d_ref_clock;
     uint8_t d_bits_per_sample;
+    gr::msg_queue::sptr d_queue;
 
 public:
-    labsat23_source(const char *signal_file_basename, int channel_selector);
     ~labsat23_source();
     int general_work(int noutput_items,
         gr_vector_int &ninput_items,

src/algorithms/telemetry_decoder/gnuradio_blocks/galileo_telemetry_decoder_gs.cc

@@ -215,7 +215,7 @@ galileo_telemetry_decoder_gs::galileo_telemetry_decoder_gs(
     d_flag_preamble = false;
     d_channel = 0;
     flag_TOW_set = false;
-
+    flag_PLL_180_deg_phase_locked = false;
     d_symbol_history.set_capacity(d_required_symbols + 1);
 
     // vars for Viterbi decoder
@@ -488,9 +488,6 @@ void galileo_telemetry_decoder_gs::set_channel(int32_t channel)
 int galileo_telemetry_decoder_gs::general_work(int noutput_items __attribute__((unused)), gr_vector_int &ninput_items __attribute__((unused)),
     gr_vector_const_void_star &input_items, gr_vector_void_star &output_items)
 {
-    int32_t corr_value = 0;
-    int32_t preamble_diff = 0;
-
     auto **out = reinterpret_cast<Gnss_Synchro **>(&output_items[0]);            // Get the output buffer pointer
     const auto **in = reinterpret_cast<const Gnss_Synchro **>(&input_items[0]);  // Get the input buffer pointer
 
@@ -513,27 +510,29 @@ int galileo_telemetry_decoder_gs::general_work(int noutput_items __attribute__((
                     d_sent_tlm_failed_msg = true;
                 }
         }
-    if (d_symbol_history.size() > d_required_symbols)
-        {
-            // ******* preamble correlation ********
-            for (int32_t i = 0; i < d_samples_per_preamble; i++)
-                {
-                    if (d_symbol_history[i] < 0.0)  // symbols clipping
-                        {
-                            corr_value -= d_preamble_samples[i];
-                        }
-                    else
-                        {
-                            corr_value += d_preamble_samples[i];
-                        }
-                }
-        }
 
     // ******* frame sync ******************
     switch (d_stat)
         {
         case 0:  // no preamble information
             {
+                //correlate with preamble
+                int32_t corr_value = 0;
+                if (d_symbol_history.size() > d_required_symbols)
+                    {
+                        // ******* preamble correlation ********
+                        for (int32_t i = 0; i < d_samples_per_preamble; i++)
+                            {
+                                if (d_symbol_history[i] < 0.0)  // symbols clipping
+                                    {
+                                        corr_value -= d_preamble_samples[i];
+                                    }
+                                else
+                                    {
+                                        corr_value += d_preamble_samples[i];
+                                    }
+                            }
+                    }
                 if (abs(corr_value) >= d_samples_per_preamble)
                     {
                         d_preamble_index = d_sample_counter;  // record the preamble sample stamp
@@ -544,6 +543,24 @@ int galileo_telemetry_decoder_gs::general_work(int noutput_items __attribute__((
             }
         case 1:  // possible preamble lock
             {
+                //correlate with preamble
+                int32_t corr_value = 0;
+                int32_t preamble_diff = 0;
+                if (d_symbol_history.size() > d_required_symbols)
+                    {
+                        // ******* preamble correlation ********
+                        for (int32_t i = 0; i < d_samples_per_preamble; i++)
+                            {
+                                if (d_symbol_history[i] < 0.0)  // symbols clipping
+                                    {
+                                        corr_value -= d_preamble_samples[i];
+                                    }
+                                else
+                                    {
+                                        corr_value += d_preamble_samples[i];
+                                    }
+                            }
+                    }
                 if (abs(corr_value) >= d_samples_per_preamble)
                     {
                         // check preamble separation
@@ -554,6 +571,7 @@ int galileo_telemetry_decoder_gs::general_work(int noutput_items __attribute__((
                                 DLOG(INFO) << "Starting page decoder for Galileo satellite " << this->d_satellite;
                                 d_preamble_index = d_sample_counter;  // record the preamble sample stamp
                                 d_CRC_error_counter = 0;
+                                if (corr_value < 0) flag_PLL_180_deg_phase_locked = true;
                                 d_stat = 2;
                             }
                         else
@@ -576,7 +594,7 @@ int galileo_telemetry_decoder_gs::general_work(int noutput_items __attribute__((
                             case 1:  // INAV
                                      // NEW Galileo page part is received
                                 // 0. fetch the symbols into an array
-                                if (corr_value > 0)  // normal PLL lock
+                                if (flag_PLL_180_deg_phase_locked == false)  // normal PLL lock
                                     {
                                         for (uint32_t i = 0; i < d_frame_length_symbols; i++)
                                             {
@@ -595,7 +613,7 @@ int galileo_telemetry_decoder_gs::general_work(int noutput_items __attribute__((
                             case 2:  // FNAV
                                      // NEW Galileo page part is received
                                 // 0. fetch the symbols into an array
-                                if (corr_value > 0)  // normal PLL lock
+                                if (flag_PLL_180_deg_phase_locked == false)  // normal PLL lock
                                     {
                                         int k = 0;
                                         for (uint32_t i = 0; i < d_frame_length_symbols; i++)

src/algorithms/telemetry_decoder/gnuradio_blocks/galileo_telemetry_decoder_gs.h

@@ -102,6 +102,7 @@ private:
     bool d_sent_tlm_failed_msg;
     uint32_t d_stat;
     bool d_flag_frame_sync;
+    bool flag_PLL_180_deg_phase_locked;
 
     bool d_flag_parity;
     bool d_flag_preamble;

src/algorithms/telemetry_decoder/gnuradio_blocks/gps_l1_ca_telemetry_decoder_gs.cc

@@ -68,55 +68,66 @@ gps_l1_ca_telemetry_decoder_gs::gps_l1_ca_telemetry_decoder_gs(
     this->message_port_register_out(pmt::mp("telemetry_to_trk"));
     d_last_valid_preamble = 0;
     d_sent_tlm_failed_msg = false;
-    d_max_symbols_without_valid_frame = GPS_SUBFRAME_BITS * GPS_CA_TELEMETRY_SYMBOLS_PER_BIT * 5;  //rise alarm if 5 consecutive subframes have no valid CRC
+
 
     // initialize internal vars
     d_dump = dump;
     d_satellite = Gnss_Satellite(satellite.get_system(), satellite.get_PRN());
+    DLOG(INFO) << "Initializing GPS L1 TELEMETRY DECODER";
 
+    d_bits_per_preamble = GPS_CA_PREAMBLE_LENGTH_BITS;
+    d_samples_per_preamble = d_bits_per_preamble * GPS_CA_TELEMETRY_SYMBOLS_PER_BIT;
+    d_preamble_period_symbols = GPS_SUBFRAME_BITS * GPS_CA_TELEMETRY_SYMBOLS_PER_BIT;
     // set the preamble
-    uint16_t preambles_bits[GPS_CA_PREAMBLE_LENGTH_BITS] = GPS_PREAMBLE;
+    d_required_symbols = GPS_SUBFRAME_BITS * GPS_CA_TELEMETRY_SYMBOLS_PER_BIT;
-
     // preamble bits to sampled symbols
-    d_preambles_symbols = static_cast<int32_t *>(volk_gnsssdr_malloc(GPS_CA_PREAMBLE_LENGTH_SYMBOLS * sizeof(int32_t), volk_gnsssdr_get_alignment()));
+    d_preamble_samples = static_cast<int32_t *>(volk_gnsssdr_malloc(d_samples_per_preamble * sizeof(int32_t), volk_gnsssdr_get_alignment()));
+    d_frame_length_symbols = GPS_SUBFRAME_BITS * GPS_CA_TELEMETRY_SYMBOLS_PER_BIT;
+    d_max_symbols_without_valid_frame = d_required_symbols * 10;  //rise alarm 1 minute without valid tlm
+    d_page_part_symbols = static_cast<double *>(volk_gnsssdr_malloc(d_frame_length_symbols * sizeof(double), volk_gnsssdr_get_alignment()));
     int32_t n = 0;
-    for (uint16_t preambles_bit : preambles_bits)
+    for (int32_t i = 0; i < d_bits_per_preamble; i++)
         {
-            for (uint32_t j = 0; j < GPS_CA_TELEMETRY_SYMBOLS_PER_BIT; j++)
+            if (GPS_CA_PREAMBLE.at(i) == '1')
                 {
-                    if (preambles_bit == 1)
+                    for (uint32_t j = 0; j < GPS_CA_TELEMETRY_SYMBOLS_PER_BIT; j++)
                         {
-                            d_preambles_symbols[n] = 1;
+                            d_preamble_samples[n] = 1;
+                            n++;
                         }
-                    else
+                }
+            else
+                {
+                    for (uint32_t j = 0; j < GPS_CA_TELEMETRY_SYMBOLS_PER_BIT; j++)
                         {
-                            d_preambles_symbols[n] = -1;
+                            d_preamble_samples[n] = -1;
+                            n++;
                         }
-                    n++;
                 }
         }
-    d_stat = 0U;
+    d_sample_counter = 0ULL;
+    d_stat = 0;
+    d_preamble_index = 0ULL;
+
     d_flag_frame_sync = false;
-    d_prev_GPS_frame_4bytes = 0;
+
-    d_TOW_at_Preamble_ms = 0;
+    d_flag_parity = false;
-    flag_TOW_set = false;
-    d_flag_preamble = false;
-    d_flag_new_tow_available = false;
-    d_channel = 0;
-    flag_PLL_180_deg_phase_locked = false;
-    d_preamble_time_samples = 0ULL;
     d_TOW_at_current_symbol_ms = 0;
-    d_symbol_history.set_capacity(GPS_CA_PREAMBLE_LENGTH_SYMBOLS);
+    d_TOW_at_Preamble_ms = 0;
-    d_crc_error_synchronization_counter = 0;
+    d_CRC_error_counter = 0;
-    d_current_subframe_symbol = 0;
+    d_flag_preamble = false;
-    d_sample_counter = 0;
+    d_channel = 0;
+    flag_TOW_set = false;
+    flag_PLL_180_deg_phase_locked = false;
+    d_prev_GPS_frame_4bytes = 0;
+    d_symbol_history.set_capacity(d_required_symbols);
 }
 
 
 gps_l1_ca_telemetry_decoder_gs::~gps_l1_ca_telemetry_decoder_gs()
 {
-    volk_gnsssdr_free(d_preambles_symbols);
+    volk_gnsssdr_free(d_preamble_samples);
-    d_symbol_history.clear();
+    volk_gnsssdr_free(d_page_part_symbols);
     if (d_dump_file.is_open() == true)
         {
             try
@@ -209,11 +220,11 @@ bool gps_l1_ca_telemetry_decoder_gs::decode_subframe()
     bool subframe_synchro_confirmation = false;
     bool CRC_ok = true;
 
-    for (float d_subframe_symbol : d_subframe_symbols)
+    for (float subframe_symbol : d_symbol_history)
         {
             // ******* SYMBOL TO BIT *******
             // extended correlation to bit period is enabled in tracking!
-            symbol_accumulator += d_subframe_symbol;  // accumulate the input value in d_symbol_accumulator
+            symbol_accumulator += subframe_symbol;  // accumulate the input value in d_symbol_accumulator
             symbol_accumulator_counter++;
             if (symbol_accumulator_counter == 20)
                 {
@@ -221,6 +232,11 @@ bool gps_l1_ca_telemetry_decoder_gs::decode_subframe()
                     if (symbol_accumulator > 0)
                         {
                             GPS_frame_4bytes += 1;  // insert the telemetry bit in LSB
+                            //std::cout << "1";
+                        }
+                    else
+                        {
+                            //std::cout << "0";
                         }
                     symbol_accumulator = 0;
                     symbol_accumulator_counter = 0;
@@ -276,7 +292,7 @@ bool gps_l1_ca_telemetry_decoder_gs::decode_subframe()
     // NEW GPS SUBFRAME HAS ARRIVED!
     if (CRC_ok)
         {
-            int32_t subframe_ID = d_nav.subframe_decoder(subframe);  //d ecode the subframe
+            int32_t subframe_ID = d_nav.subframe_decoder(subframe);  //decode the subframe
             if (subframe_ID > 0 and subframe_ID < 6)
                 {
                     std::cout << "New GPS NAV message received in channel " << this->d_channel << ": "
@@ -313,7 +329,6 @@ bool gps_l1_ca_telemetry_decoder_gs::decode_subframe()
                         default:
                             break;
                         }
-                    d_flag_new_tow_available = true;
                 }
             else
                 {
@@ -336,30 +351,18 @@ void gps_l1_ca_telemetry_decoder_gs::reset()
 int gps_l1_ca_telemetry_decoder_gs::general_work(int noutput_items __attribute__((unused)), gr_vector_int &ninput_items __attribute__((unused)),
     gr_vector_const_void_star &input_items, gr_vector_void_star &output_items)
 {
-    int32_t preamble_diff_ms = 0;
-
     auto **out = reinterpret_cast<Gnss_Synchro **>(&output_items[0]);            // Get the output buffer pointer
     const auto **in = reinterpret_cast<const Gnss_Synchro **>(&input_items[0]);  // Get the input buffer pointer
 
-    Gnss_Synchro current_symbol{};  // structure to save the synchronization information and send the output object to the next block
     // 1. Copy the current tracking output
-    current_symbol = in[0][0];
+    Gnss_Synchro current_symbol = in[0][0];
-
+    // add new symbol to the symbol queue
-    // record the oldest subframe symbol before inserting a new symbol into the circular buffer
+    d_symbol_history.push_back(current_symbol.Prompt_I);
-    if (d_current_subframe_symbol < GPS_SUBFRAME_MS and !d_symbol_history.empty())
-        {
-            d_subframe_symbols[d_current_subframe_symbol] = d_symbol_history[0].Prompt_I;
-            d_current_subframe_symbol++;
-        }
-
-    d_symbol_history.push_back(current_symbol);  // add new symbol to the symbol queue
-    consume_each(1);
-
-    d_flag_preamble = false;
-
-    // check if there is a problem with the telemetry of the current satellite
     d_sample_counter++;  // count for the processed symbols
-    if (d_sent_tlm_failed_msg == false)
+    consume_each(1);
+    d_flag_preamble = false;
+    // check if there is a problem with the telemetry of the current satellite
+    if (d_stat < 2 and d_sent_tlm_failed_msg == false)
         {
             if ((d_sample_counter - d_last_valid_preamble) > d_max_symbols_without_valid_frame)
                 {
@@ -369,108 +372,123 @@ int gps_l1_ca_telemetry_decoder_gs::general_work(int noutput_items __attribute__
                 }
         }
 
-
-    // ******* preamble correlation ********
-    int32_t corr_value = 0;
-    if ((d_symbol_history.size() == GPS_CA_PREAMBLE_LENGTH_SYMBOLS))
-        {
-            int i = 0;
-            for (const auto &iter : d_symbol_history)
-                {
-                    if (iter.Flag_valid_symbol_output == true)
-                        {
-                            if (iter.Prompt_I < 0.0)  // symbols clipping
-                                {
-                                    corr_value -= d_preambles_symbols[i];
-                                }
-                            else
-                                {
-                                    corr_value += d_preambles_symbols[i];
-                                }
-                        }
-                    i++;
-                }
-        }
-
     // ******* frame sync ******************
-    if (std::abs(corr_value) == GPS_CA_PREAMBLE_LENGTH_SYMBOLS)
+    switch (d_stat)
         {
-            //TODO: Rewrite with state machine
+        case 0:  // no preamble information
-            if (d_stat == 0)
+            {
-                {
+                //correlate with preamble
-                    // record the preamble sample stamp
+                int32_t corr_value = 0;
-                    d_preamble_time_samples = d_symbol_history[0].Tracking_sample_counter;  // record the preamble sample stamp
+                if (d_symbol_history.size() >= GPS_CA_PREAMBLE_LENGTH_SYMBOLS)
-                    DLOG(INFO) << "Preamble detection for SAT " << this->d_satellite << "d_symbol_history[0].Tracking_sample_counter=" << d_symbol_history[0].Tracking_sample_counter;
+                    {
-                    d_stat = 1;  // enter into frame pre-detection status
+                        // ******* preamble correlation ********
-                }
+                        for (int32_t i = 0; i < GPS_CA_PREAMBLE_LENGTH_SYMBOLS; i++)
-            else if (d_stat == 1)  // check 6 seconds of preamble separation
+                            {
-                {
+                                if (d_symbol_history[i] < 0.0)  // symbols clipping
-                    preamble_diff_ms = std::round(((static_cast<double>(d_symbol_history[0].Tracking_sample_counter) - static_cast<double>(d_preamble_time_samples)) / static_cast<double>(d_symbol_history[0].fs)) * 1000.0);
+                                    {
-                    if (std::abs(preamble_diff_ms - GPS_SUBFRAME_MS) % GPS_SUBFRAME_MS == 0)
+                                        corr_value -= d_preamble_samples[i];
-                        {
+                                    }
-                            DLOG(INFO) << "Preamble confirmation for SAT " << this->d_satellite;
+                                else
-                            d_flag_preamble = true;
+                                    {
-                            d_preamble_time_samples = d_symbol_history[0].Tracking_sample_counter;  // record the PRN start sample index associated to the preamble
+                                        corr_value += d_preamble_samples[i];
-                            if (!d_flag_frame_sync)
+                                    }
-                                {
+                            }
-                                    d_flag_frame_sync = true;
+                    }
-                                    if (corr_value < 0)
+                if (abs(corr_value) >= d_samples_per_preamble)
-                                        {
+                    {
-                                            flag_PLL_180_deg_phase_locked = true;  // PLL is locked to opposite phase!
+                        d_preamble_index = d_sample_counter;  // record the preamble sample stamp
-                                            DLOG(INFO) << " PLL in opposite phase for Sat " << this->d_satellite.get_PRN();
+                        DLOG(INFO) << "Preamble detection for GPS L1 satellite " << this->d_satellite;
-                                        }
+                        d_stat = 1;  // enter into frame pre-detection status
-                                    else
+                    }
-                                        {
+                break;
-                                            flag_PLL_180_deg_phase_locked = false;
+            }
-                                        }
+        case 1:  // possible preamble lock
-                                    DLOG(INFO) << " Frame sync SAT " << this->d_satellite << " with preamble start at "
+            {
-                                               << static_cast<double>(d_preamble_time_samples) / static_cast<double>(d_symbol_history[0].fs) << " [s]";
+                //correlate with preamble
-                                }
+                int32_t corr_value = 0;
+                int32_t preamble_diff = 0;
+                if (d_symbol_history.size() >= GPS_CA_PREAMBLE_LENGTH_SYMBOLS)
+                    {
+                        // ******* preamble correlation ********
+                        for (int32_t i = 0; i < GPS_CA_PREAMBLE_LENGTH_SYMBOLS; i++)
+                            {
+                                if (d_symbol_history[i] < 0.0)  // symbols clipping
+                                    {
+                                        corr_value -= d_preamble_samples[i];
+                                    }
+                                else
+                                    {
+                                        corr_value += d_preamble_samples[i];
+                                    }
+                            }
+                    }
+                if (abs(corr_value) >= d_samples_per_preamble)
+                    {
+                        // check preamble separation
+                        preamble_diff = static_cast<int32_t>(d_sample_counter - d_preamble_index);
+                        if (abs(preamble_diff - d_preamble_period_symbols) == 0)
+                            {
+                                DLOG(INFO) << "Preamble confirmation for SAT " << this->d_satellite;
+                                d_preamble_index = d_sample_counter;  // record the preamble sample stamp
+                                if (corr_value < 0) flag_PLL_180_deg_phase_locked = true;
+                                d_stat = 2;
+                            }
+                        else
+                            {
+                                if (preamble_diff > d_preamble_period_symbols)
+                                    {
+                                        d_stat = 0;  // start again
+                                    }
+                            }
+                    }
+                break;
+            }
+        case 2:  // preamble acquired
+            {
+                if (d_sample_counter >= d_preamble_index + static_cast<uint64_t>(d_preamble_period_symbols))
+                    {
+                        DLOG(INFO) << "Preamble received for SAT " << this->d_satellite << "d_sample_counter=" << d_sample_counter << "\n";
+                        // call the decoder
+                        // 0. fetch the symbols into an array
+                        d_preamble_index = d_sample_counter;  // record the preamble sample stamp (t_P)
 
-                            // try to decode the subframe:
+                        if (decode_subframe())
-                            if (decode_subframe() == false)
+                            {
-                                {
+                                d_CRC_error_counter = 0;
-                                    d_crc_error_synchronization_counter++;
+                                d_flag_preamble = true;  // valid preamble indicator (initialized to false every work())
-                                    if (d_crc_error_synchronization_counter > 3)
+                                d_last_valid_preamble = d_sample_counter;
-                                        {
+                                if (!d_flag_frame_sync)
-                                            DLOG(INFO) << "TOO MANY CRC ERRORS: Lost of frame sync SAT " << this->d_satellite << std::endl;
+                                    {
-                                            d_stat = 0;  // lost of frame sync
+                                        d_flag_frame_sync = true;
-                                            d_flag_frame_sync = false;
+                                        DLOG(INFO) << " Frame sync SAT " << this->d_satellite;
-                                            flag_TOW_set = false;
+                                    }
-                                            d_crc_error_synchronization_counter = 0;
+                            }
-                                        }
+                        else
-                                }
+                            {
-                            d_current_subframe_symbol = 0;
+                                d_CRC_error_counter++;
-                        }
+                                d_preamble_index = d_sample_counter;  // record the preamble sample stamp
-                }
+                                if (d_CRC_error_counter > 2)
-        }
+                                    {
-    else
+                                        DLOG(INFO) << "Lost of frame sync SAT " << this->d_satellite;
-        {
+                                        d_flag_frame_sync = false;
-            if (d_stat == 1)
+                                        d_stat = 0;
-                {
+                                        d_TOW_at_current_symbol_ms = 0;
-                    preamble_diff_ms = round(((static_cast<double>(d_symbol_history[0].Tracking_sample_counter) - static_cast<double>(d_preamble_time_samples)) / static_cast<double>(d_symbol_history[0].fs)) * 1000.0);
+                                        d_TOW_at_Preamble_ms = 0;
-                    if (preamble_diff_ms > GPS_SUBFRAME_MS)
+                                        d_CRC_error_counter = 0;
-                        {
+                                        flag_TOW_set = false;
-                            DLOG(INFO) << "Lost of frame sync SAT " << this->d_satellite << " preamble_diff= " << preamble_diff_ms;
+                                    }
-                            //  std::cout << "Lost of frame sync SAT " << this->d_satellite << " preamble_diff= " << preamble_diff_ms << std::endl;
+                            }
-                            d_stat = 0;  // lost of frame sync
+                    }
-                            d_flag_frame_sync = false;
+                break;
-                            flag_TOW_set = false;
+            }
-                            d_current_subframe_symbol = 0;
-                            d_crc_error_synchronization_counter = 0;
-                            d_TOW_at_current_symbol_ms = 0;
-                        }
-                }
         }
 
     // 2. Add the telemetry decoder information
-    if (this->d_flag_preamble == true and d_flag_new_tow_available == true)
+    if (d_flag_preamble == true)
         {
-            d_TOW_at_current_symbol_ms = static_cast<uint32_t>(d_nav.d_TOW * 1000.0) + GPS_CA_PREAMBLE_DURATION_MS;
+            d_TOW_at_current_symbol_ms = static_cast<uint32_t>(d_nav.d_TOW * 1000.0);
             d_TOW_at_Preamble_ms = static_cast<uint32_t>(d_nav.d_TOW * 1000.0);
             flag_TOW_set = true;
-            d_flag_new_tow_available = false;
-            d_last_valid_preamble = d_sample_counter;
         }
     else
         {

src/algorithms/telemetry_decoder/gnuradio_blocks/gps_l1_ca_telemetry_decoder_gs.h

@@ -73,46 +73,45 @@ private:
     gps_l1_ca_make_telemetry_decoder_gs(const Gnss_Satellite &satellite, bool dump);
 
     gps_l1_ca_telemetry_decoder_gs(const Gnss_Satellite &satellite, bool dump);
-
     bool gps_word_parityCheck(uint32_t gpsword);
-
     bool decode_subframe();
-    bool new_decoder();
+
-    int d_crc_error_synchronization_counter;
+    // new
+    int32_t d_bits_per_preamble;
+    int32_t d_samples_per_preamble;
+    int32_t d_preamble_period_symbols;
+    int32_t *d_preamble_samples;
+    uint32_t d_required_symbols;
+    uint32_t d_frame_length_symbols;
+    double *d_page_part_symbols;
+    bool flag_PLL_180_deg_phase_locked;
+    // navigation message vars
+    Gps_Navigation_Message d_nav;
+    uint32_t d_prev_GPS_frame_4bytes;
+
+    boost::circular_buffer<float> d_symbol_history;
+
     uint64_t d_sample_counter;
-    bool d_sent_tlm_failed_msg;
+    uint64_t d_preamble_index;
     uint64_t d_last_valid_preamble;
     uint32_t d_max_symbols_without_valid_frame;
 
-    int *d_preambles_symbols;
+    bool d_sent_tlm_failed_msg;
     uint32_t d_stat;
     bool d_flag_frame_sync;
-
+    bool d_flag_parity;
-    // symbols
-    boost::circular_buffer<Gnss_Synchro> d_symbol_history;
-    float d_subframe_symbols[GPS_SUBFRAME_MS]{};  // symbols per subframe
-    int d_current_subframe_symbol;
-
-    // bits and frame
-    uint32_t d_prev_GPS_frame_4bytes;
     bool d_flag_preamble;
-    bool d_flag_new_tow_available;
+    int32_t d_CRC_error_counter;
 
-    // navigation message vars
-    Gps_Navigation_Message d_nav;
 
-    bool d_dump;
     Gnss_Satellite d_satellite;
-    int d_channel;
+    int32_t d_channel;
-
-    uint64_t d_preamble_time_samples;
 
     uint32_t d_TOW_at_Preamble_ms;
     uint32_t d_TOW_at_current_symbol_ms;
 
     bool flag_TOW_set;
-    bool flag_PLL_180_deg_phase_locked;
+    bool d_dump;
-
     std::string d_dump_filename;
     std::ofstream d_dump_file;
 };

src/algorithms/tracking/adapters/galileo_e1_dll_pll_veml_tracking_fpga.cc

@@ -48,6 +48,11 @@
 #include <cstring>   // for memcpy
 #include <iostream>  // for operator<<,
 
+// the following flags are FPGA-specific and they are using arrange the values of the local code in the way the FPGA
+// expects. This arrangement is done in the initialisation to avoid consuming unnecessary clock cycles during tracking.
+#define LOCAL_CODE_FPGA_ENABLE_WRITE_MEMORY 0x0C000000      // flag that enables WE (Write Enable) of the local code FPGA
+#define LOCAL_CODE_FPGA_CORRELATOR_SELECT_COUNT 0x20000000  // flag that selects the writing of the pilot code in the FPGA (as opposed to the data code)
+
 
 GalileoE1DllPllVemlTrackingFpga::GalileoE1DllPllVemlTrackingFpga(
     ConfigurationInterface* configuration, const std::string& role,
@@ -56,8 +61,6 @@ GalileoE1DllPllVemlTrackingFpga::GalileoE1DllPllVemlTrackingFpga(
     Dll_Pll_Conf_Fpga trk_param_fpga = Dll_Pll_Conf_Fpga();
     DLOG(INFO) << "role " << role;
     //################# CONFIGURATION PARAMETERS ########################
-    std::string default_item_type = "gr_complex";
-    std::string item_type = configuration->property(role + ".item_type", default_item_type);
     int32_t fs_in_deprecated = configuration->property("GNSS-SDR.internal_fs_hz", 2048000);
     int32_t fs_in = configuration->property("GNSS-SDR.internal_fs_sps", fs_in_deprecated);
     trk_param_fpga.fs_in = fs_in;
@@ -68,16 +71,76 @@ GalileoE1DllPllVemlTrackingFpga::GalileoE1DllPllVemlTrackingFpga(
     trk_param_fpga.dump_filename = dump_filename;
     bool dump_mat = configuration->property(role + ".dump_mat", true);
     trk_param_fpga.dump_mat = dump_mat;
+    trk_param_fpga.high_dyn = configuration->property(role + ".high_dyn", false);
+    if (configuration->property(role + ".smoother_length", 10) < 1)
+        {
+            trk_param_fpga.smoother_length = 1;
+            std::cout << TEXT_RED << "WARNING: Gal. E1. smoother_length must be bigger than 0. It has been set to 1" << TEXT_RESET << std::endl;
+        }
+    else
+        {
+            trk_param_fpga.smoother_length = configuration->property(role + ".smoother_length", 10);
+        }
+
     float pll_bw_hz = configuration->property(role + ".pll_bw_hz", 5.0);
-    if (FLAGS_pll_bw_hz != 0.0) pll_bw_hz = static_cast<float>(FLAGS_pll_bw_hz);
+    if (FLAGS_pll_bw_hz != 0.0)
+        {
+            pll_bw_hz = static_cast<float>(FLAGS_pll_bw_hz);
+        }
     trk_param_fpga.pll_bw_hz = pll_bw_hz;
     float dll_bw_hz = configuration->property(role + ".dll_bw_hz", 0.5);
-    if (FLAGS_dll_bw_hz != 0.0) dll_bw_hz = static_cast<float>(FLAGS_dll_bw_hz);
+    if (FLAGS_dll_bw_hz != 0.0)
+        {
+            dll_bw_hz = static_cast<float>(FLAGS_dll_bw_hz);
+        }
     trk_param_fpga.dll_bw_hz = dll_bw_hz;
     float pll_bw_narrow_hz = configuration->property(role + ".pll_bw_narrow_hz", 2.0);
     trk_param_fpga.pll_bw_narrow_hz = pll_bw_narrow_hz;
     float dll_bw_narrow_hz = configuration->property(role + ".dll_bw_narrow_hz", 0.25);
     trk_param_fpga.dll_bw_narrow_hz = dll_bw_narrow_hz;
+
+    int dll_filter_order = configuration->property(role + ".dll_filter_order", 2);
+    if (dll_filter_order < 1)
+        {
+            LOG(WARNING) << "dll_filter_order parameter must be 1, 2 or 3. Set to 1.";
+            dll_filter_order = 1;
+        }
+    if (dll_filter_order > 3)
+        {
+            LOG(WARNING) << "dll_filter_order parameter must be 1, 2 or 3. Set to 3.";
+            dll_filter_order = 3;
+        }
+    trk_param_fpga.dll_filter_order = dll_filter_order;
+
+    int pll_filter_order = configuration->property(role + ".pll_filter_order", 3);
+    if (pll_filter_order < 2)
+        {
+            LOG(WARNING) << "pll_filter_order parameter must be 2 or 3. Set to 2.";
+            pll_filter_order = 2;
+        }
+    if (pll_filter_order > 3)
+        {
+            LOG(WARNING) << "pll_filter_order parameter must be 2 or 3. Set to 3.";
+            pll_filter_order = 3;
+        }
+    trk_param_fpga.pll_filter_order = pll_filter_order;
+
+    if (pll_filter_order == 2)
+        {
+            trk_param_fpga.fll_filter_order = 1;
+        }
+    if (pll_filter_order == 3)
+        {
+            trk_param_fpga.fll_filter_order = 2;
+        }
+
+    bool enable_fll_pull_in = configuration->property(role + ".enable_fll_pull_in", false);
+    trk_param_fpga.enable_fll_pull_in = enable_fll_pull_in;
+    float fll_bw_hz = configuration->property(role + ".fll_bw_hz", 35.0);
+    trk_param_fpga.fll_bw_hz = fll_bw_hz;
+    float pull_in_time_s = configuration->property(role + ".pull_in_time_s", 2.0);
+    trk_param_fpga.pull_in_time_s = pull_in_time_s;
+
     int32_t extend_correlation_symbols = configuration->property(role + ".extend_correlation_symbols", 1);
     float early_late_space_chips = configuration->property(role + ".early_late_space_chips", 0.15);
     trk_param_fpga.early_late_space_chips = early_late_space_chips;
@@ -111,16 +174,29 @@ GalileoE1DllPllVemlTrackingFpga::GalileoE1DllPllVemlTrackingFpga(
     char sig_[3] = "1B";
     std::memcpy(trk_param_fpga.signal, sig_, 3);
     int32_t cn0_samples = configuration->property(role + ".cn0_samples", 20);
-    if (FLAGS_cn0_samples != 20) cn0_samples = FLAGS_cn0_samples;
+    if (FLAGS_cn0_samples != 20)
+        {
+            cn0_samples = FLAGS_cn0_samples;
+        }
+
     trk_param_fpga.cn0_samples = cn0_samples;
     int32_t cn0_min = configuration->property(role + ".cn0_min", 25);
-    if (FLAGS_cn0_min != 25) cn0_min = FLAGS_cn0_min;
+    if (FLAGS_cn0_min != 25)
+        {
+            cn0_min = FLAGS_cn0_min;
+        }
     trk_param_fpga.cn0_min = cn0_min;
     int32_t max_lock_fail = configuration->property(role + ".max_lock_fail", 50);
-    if (FLAGS_max_lock_fail != 50) max_lock_fail = FLAGS_max_lock_fail;
+    if (FLAGS_max_lock_fail != 50)
+        {
+            max_lock_fail = FLAGS_max_lock_fail;
+        }
     trk_param_fpga.max_lock_fail = max_lock_fail;
     double carrier_lock_th = configuration->property(role + ".carrier_lock_th", 0.85);
-    if (FLAGS_carrier_lock_th != 0.85) carrier_lock_th = FLAGS_carrier_lock_th;
+    if (FLAGS_carrier_lock_th != 0.85)
+        {
+            carrier_lock_th = FLAGS_carrier_lock_th;
+        }
     trk_param_fpga.carrier_lock_th = carrier_lock_th;
 
     // FPGA configuration parameters
@@ -158,19 +234,39 @@ GalileoE1DllPllVemlTrackingFpga::GalileoE1DllPllVemlTrackingFpga(
                     galileo_e1_code_gen_sinboc11_float(ca_codes_f, pilot_signal, PRN);
                     galileo_e1_code_gen_sinboc11_float(data_codes_f, data_signal, PRN);
 
+                    // The code is generated as a series of 1s and -1s. In order to store the values using only one bit, a -1 is stored as a 0 in the FPGA
                     for (uint32_t s = 0; s < 2 * GALILEO_E1_B_CODE_LENGTH_CHIPS; s++)
                         {
-                            d_ca_codes[static_cast<int32_t>(GALILEO_E1_B_CODE_LENGTH_CHIPS) * 2 * (PRN - 1) + s] = static_cast<int32_t>(ca_codes_f[s]);
+                            int32_t tmp_value = static_cast<int32_t>(ca_codes_f[s]);
-                            d_data_codes[static_cast<int32_t>(GALILEO_E1_B_CODE_LENGTH_CHIPS) * 2 * (PRN - 1) + s] = static_cast<int32_t>(data_codes_f[s]);
+                            if (tmp_value < 0)
+                                {
+                                    tmp_value = 0;
+                                }
+                            tmp_value = tmp_value | LOCAL_CODE_FPGA_ENABLE_WRITE_MEMORY;
+                            d_ca_codes[static_cast<int32_t>(GALILEO_E1_B_CODE_LENGTH_CHIPS) * 2 * (PRN - 1) + s] = tmp_value;
+                            tmp_value = static_cast<int32_t>(data_codes_f[s]);
+                            if (tmp_value < 0)
+                                {
+                                    tmp_value = 0;
+                                }
+                            tmp_value = tmp_value | LOCAL_CODE_FPGA_ENABLE_WRITE_MEMORY | LOCAL_CODE_FPGA_CORRELATOR_SELECT_COUNT;
+                            d_data_codes[static_cast<int32_t>(GALILEO_E1_B_CODE_LENGTH_CHIPS) * 2 * (PRN - 1) + s] = tmp_value;
                         }
                 }
             else
                 {
                     galileo_e1_code_gen_sinboc11_float(ca_codes_f, data_signal, PRN);
 
+                    // The code is generated as a series of 1s and -1s. In order to store the values using only one bit, a -1 is stored as a 0 in the FPGA
                     for (uint32_t s = 0; s < 2 * GALILEO_E1_B_CODE_LENGTH_CHIPS; s++)
                         {
-                            d_ca_codes[static_cast<int32_t>(GALILEO_E1_B_CODE_LENGTH_CHIPS) * 2 * (PRN - 1) + s] = static_cast<int32_t>(ca_codes_f[s]);
+                            int32_t tmp_value = static_cast<int32_t>(ca_codes_f[s]);
+                            if (tmp_value < 0)
+                                {
+                                    tmp_value = 0;
+                                }
+                            tmp_value = tmp_value | LOCAL_CODE_FPGA_ENABLE_WRITE_MEMORY;
+                            d_ca_codes[static_cast<int32_t>(GALILEO_E1_B_CODE_LENGTH_CHIPS) * 2 * (PRN - 1) + s] = tmp_value;
                         }
                 }
         }

src/algorithms/tracking/adapters/galileo_e5a_dll_pll_tracking_fpga.cc

@@ -45,6 +45,11 @@
 #include <cstring>  // for memcpy
 #include <iostream>
 
+// the following flags are FPGA-specific and they are using arrange the values of the local code in the way the FPGA
+// expects. This arrangement is done in the initialisation to avoid consuming unnecessary clock cycles during tracking.
+#define LOCAL_CODE_FPGA_ENABLE_WRITE_MEMORY 0x0C000000      // flag that enables WE (Write Enable) of the local code FPGA
+#define LOCAL_CODE_FPGA_CORRELATOR_SELECT_COUNT 0x20000000  // flag that selects the writing of the pilot code in the FPGA (as opposed to the data code)
+
 
 GalileoE5aDllPllTrackingFpga::GalileoE5aDllPllTrackingFpga(
     ConfigurationInterface *configuration, const std::string &role,
@@ -53,8 +58,6 @@ GalileoE5aDllPllTrackingFpga::GalileoE5aDllPllTrackingFpga(
     Dll_Pll_Conf_Fpga trk_param_fpga = Dll_Pll_Conf_Fpga();
     DLOG(INFO) << "role " << role;
     //################# CONFIGURATION PARAMETERS ########################
-    std::string default_item_type = "gr_complex";
-    std::string item_type = configuration->property(role + ".item_type", default_item_type);
     int32_t fs_in_deprecated = configuration->property("GNSS-SDR.internal_fs_hz", 12000000);
     int32_t fs_in = configuration->property("GNSS-SDR.internal_fs_sps", fs_in_deprecated);
     trk_param_fpga.fs_in = fs_in;
@@ -65,12 +68,71 @@ GalileoE5aDllPllTrackingFpga::GalileoE5aDllPllTrackingFpga(
     trk_param_fpga.dump_filename = dump_filename;
     bool dump_mat = configuration->property(role + ".dump_mat", true);
     trk_param_fpga.dump_mat = dump_mat;
+    trk_param_fpga.high_dyn = configuration->property(role + ".high_dyn", false);
+    if (configuration->property(role + ".smoother_length", 10) < 1)
+        {
+            trk_param_fpga.smoother_length = 1;
+            std::cout << TEXT_RED << "WARNING: Gal. E5a. smoother_length must be bigger than 0. It has been set to 1" << TEXT_RESET << std::endl;
+        }
+    else
+        {
+            trk_param_fpga.smoother_length = configuration->property(role + ".smoother_length", 10);
+        }
     float pll_bw_hz = configuration->property(role + ".pll_bw_hz", 20.0);
-    if (FLAGS_pll_bw_hz != 0.0) pll_bw_hz = static_cast<float>(FLAGS_pll_bw_hz);
+    if (FLAGS_pll_bw_hz != 0.0)
+        {
+            pll_bw_hz = static_cast<float>(FLAGS_pll_bw_hz);
+        }
     trk_param_fpga.pll_bw_hz = pll_bw_hz;
     float dll_bw_hz = configuration->property(role + ".dll_bw_hz", 20.0);
-    if (FLAGS_dll_bw_hz != 0.0) dll_bw_hz = static_cast<float>(FLAGS_dll_bw_hz);
+    if (FLAGS_dll_bw_hz != 0.0)
+        {
+            dll_bw_hz = static_cast<float>(FLAGS_dll_bw_hz);
+        }
     trk_param_fpga.dll_bw_hz = dll_bw_hz;
+
+    int dll_filter_order = configuration->property(role + ".dll_filter_order", 2);
+    if (dll_filter_order < 1)
+        {
+            LOG(WARNING) << "dll_filter_order parameter must be 1, 2 or 3. Set to 1.";
+            dll_filter_order = 1;
+        }
+    if (dll_filter_order > 3)
+        {
+            LOG(WARNING) << "dll_filter_order parameter must be 1, 2 or 3. Set to 3.";
+            dll_filter_order = 3;
+        }
+    trk_param_fpga.dll_filter_order = dll_filter_order;
+
+    int pll_filter_order = configuration->property(role + ".pll_filter_order", 3);
+    if (pll_filter_order < 2)
+        {
+            LOG(WARNING) << "pll_filter_order parameter must be 2 or 3. Set to 2.";
+            pll_filter_order = 2;
+        }
+    if (pll_filter_order > 3)
+        {
+            LOG(WARNING) << "pll_filter_order parameter must be 2 or 3. Set to 3.";
+            pll_filter_order = 3;
+        }
+    trk_param_fpga.pll_filter_order = pll_filter_order;
+
+    if (pll_filter_order == 2)
+        {
+            trk_param_fpga.fll_filter_order = 1;
+        }
+    if (pll_filter_order == 3)
+        {
+            trk_param_fpga.fll_filter_order = 2;
+        }
+
+    bool enable_fll_pull_in = configuration->property(role + ".enable_fll_pull_in", false);
+    trk_param_fpga.enable_fll_pull_in = enable_fll_pull_in;
+    float fll_bw_hz = configuration->property(role + ".fll_bw_hz", 35.0);
+    trk_param_fpga.fll_bw_hz = fll_bw_hz;
+    float pull_in_time_s = configuration->property(role + ".pull_in_time_s", 2.0);
+    trk_param_fpga.pull_in_time_s = pull_in_time_s;
+
     float pll_bw_narrow_hz = configuration->property(role + ".pll_bw_narrow_hz", 5.0);
     trk_param_fpga.pll_bw_narrow_hz = pll_bw_narrow_hz;
     float dll_bw_narrow_hz = configuration->property(role + ".dll_bw_narrow_hz", 2.0);
@@ -106,17 +168,30 @@ GalileoE5aDllPllTrackingFpga::GalileoE5aDllPllTrackingFpga(
     char sig_[3] = "5X";
     std::memcpy(trk_param_fpga.signal, sig_, 3);
     int32_t cn0_samples = configuration->property(role + ".cn0_samples", 20);
-    if (FLAGS_cn0_samples != 20) cn0_samples = FLAGS_cn0_samples;
+    if (FLAGS_cn0_samples != 20)
+        {
+            cn0_samples = FLAGS_cn0_samples;
+        }
     trk_param_fpga.cn0_samples = cn0_samples;
     int32_t cn0_min = configuration->property(role + ".cn0_min", 25);
-    if (FLAGS_cn0_min != 25) cn0_min = FLAGS_cn0_min;
+    if (FLAGS_cn0_min != 25)
+        {
+            cn0_min = FLAGS_cn0_min;
+        }
     trk_param_fpga.cn0_min = cn0_min;
     int32_t max_lock_fail = configuration->property(role + ".max_lock_fail", 50);
-    if (FLAGS_max_lock_fail != 50) max_lock_fail = FLAGS_max_lock_fail;
+    if (FLAGS_max_lock_fail != 50)
+        {
+            max_lock_fail = FLAGS_max_lock_fail;
+        }
     trk_param_fpga.max_lock_fail = max_lock_fail;
     double carrier_lock_th = configuration->property(role + ".carrier_lock_th", 0.85);
-    if (FLAGS_carrier_lock_th != 0.85) carrier_lock_th = FLAGS_carrier_lock_th;
+    if (FLAGS_carrier_lock_th != 0.85)
+        {
+            carrier_lock_th = FLAGS_carrier_lock_th;
+        }
     trk_param_fpga.carrier_lock_th = carrier_lock_th;
+
     d_data_codes = nullptr;
 
     // FPGA configuration parameters
@@ -143,19 +218,41 @@ GalileoE5aDllPllTrackingFpga::GalileoE5aDllPllTrackingFpga(
     for (uint32_t PRN = 1; PRN <= GALILEO_E5A_NUMBER_OF_CODES; PRN++)
         {
             galileo_e5_a_code_gen_complex_primary(aux_code, PRN, const_cast<char *>(sig_));
+
             if (trk_param_fpga.track_pilot)
                 {
+                    // The code is generated as a series of 1s and -1s. In order to store the values using only one bit, a -1 is stored as a 0 in the FPGA
                     for (uint32_t s = 0; s < code_length_chips; s++)
                         {
-                            d_ca_codes[static_cast<int32_t>(code_length_chips) * (PRN - 1) + s] = static_cast<int32_t>(aux_code[s].imag());
+                            int32_t tmp_value = static_cast<int32_t>(aux_code[s].imag());
-                            d_data_codes[static_cast<int32_t>(code_length_chips) * (PRN - 1) + s] = static_cast<int32_t>(aux_code[s].real());
+                            if (tmp_value < 0)
+                                {
+                                    tmp_value = 0;
+                                }
+                            tmp_value = tmp_value | LOCAL_CODE_FPGA_ENABLE_WRITE_MEMORY;
+                            d_ca_codes[static_cast<int32_t>(code_length_chips) * (PRN - 1) + s] = tmp_value;
+
+                            tmp_value = static_cast<int32_t>(aux_code[s].real());
+                            if (tmp_value < 0)
+                                {
+                                    tmp_value = 0;
+                                }
+                            tmp_value = tmp_value | LOCAL_CODE_FPGA_ENABLE_WRITE_MEMORY | LOCAL_CODE_FPGA_CORRELATOR_SELECT_COUNT;
+                            d_data_codes[static_cast<int32_t>(code_length_chips) * (PRN - 1) + s] = tmp_value;
                         }
                 }
             else
                 {
+                    // The code is generated as a series of 1s and -1s. In order to store the values using only one bit, a -1 is stored as a 0 in the FPGA
                     for (uint32_t s = 0; s < code_length_chips; s++)
                         {
-                            d_ca_codes[static_cast<int32_t>(code_length_chips) * (PRN - 1) + s] = static_cast<int32_t>(aux_code[s].real());
+                            int32_t tmp_value = static_cast<int32_t>(aux_code[s].real());
+                            if (tmp_value < 0)
+                                {
+                                    tmp_value = 0;
+                                }
+                            tmp_value = tmp_value | LOCAL_CODE_FPGA_ENABLE_WRITE_MEMORY;
+                            d_ca_codes[static_cast<int32_t>(code_length_chips) * (PRN - 1) + s] = tmp_value;
                         }
                 }
         }

src/algorithms/tracking/adapters/galileo_e5a_dll_pll_tracking_fpga.h

@@ -99,7 +99,6 @@ private:
     std::string role_;
     uint32_t in_streams_;
     uint32_t out_streams_;
-
     int32_t* d_ca_codes;
     int32_t* d_data_codes;
     bool d_track_pilot;

src/algorithms/tracking/adapters/gps_l1_ca_dll_pll_tracking_fpga.cc

@@ -48,8 +48,11 @@
 #include <cstring>  // for memcpy
 #include <iostream>
 
-#define NUM_PRNs 32
+#define NUM_PRNs 32  // total number of PRNs
 
+// the following flag is FPGA-specific and they are using arrange the values of the local code in the way the FPGA
+// expects. This arrangement is done in the initialisation to avoid consuming unnecessary clock cycles during tracking.
+#define LOCAL_CODE_FPGA_ENABLE_WRITE_MEMORY 0x0C000000  // flag that enables WE (Write Enable) of the local code FPGA
 
 GpsL1CaDllPllTrackingFpga::GpsL1CaDllPllTrackingFpga(
     ConfigurationInterface* configuration, const std::string& role,
@@ -62,6 +65,17 @@ GpsL1CaDllPllTrackingFpga::GpsL1CaDllPllTrackingFpga(
     int32_t fs_in_deprecated = configuration->property("GNSS-SDR.internal_fs_hz", 2048000);
     int32_t fs_in = configuration->property("GNSS-SDR.internal_fs_sps", fs_in_deprecated);
     trk_param_fpga.fs_in = fs_in;
+    trk_param_fpga.high_dyn = configuration->property(role + ".high_dyn", false);
+    if (configuration->property(role + ".smoother_length", 10) < 1)
+        {
+            trk_param_fpga.smoother_length = 1;
+            std::cout << TEXT_RED << "WARNING: GPS L1 C/A. smoother_length must be bigger than 0. It has been set to 1" << TEXT_RESET << std::endl;
+        }
+    else
+        {
+            trk_param_fpga.smoother_length = configuration->property(role + ".smoother_length", 10);
+        }
+
     bool dump = configuration->property(role + ".dump", false);
     trk_param_fpga.dump = dump;
     std::string default_dump_filename = "./track_ch";
@@ -70,15 +84,64 @@ GpsL1CaDllPllTrackingFpga::GpsL1CaDllPllTrackingFpga(
     bool dump_mat = configuration->property(role + ".dump_mat", true);
     trk_param_fpga.dump_mat = dump_mat;
     float pll_bw_hz = configuration->property(role + ".pll_bw_hz", 50.0);
-    if (FLAGS_pll_bw_hz != 0.0) pll_bw_hz = static_cast<float>(FLAGS_pll_bw_hz);
+    if (FLAGS_pll_bw_hz != 0.0)
+        {
+            pll_bw_hz = static_cast<float>(FLAGS_pll_bw_hz);
+        }
     trk_param_fpga.pll_bw_hz = pll_bw_hz;
     float pll_bw_narrow_hz = configuration->property(role + ".pll_bw_narrow_hz", 20.0);
     trk_param_fpga.pll_bw_narrow_hz = pll_bw_narrow_hz;
     float dll_bw_narrow_hz = configuration->property(role + ".dll_bw_narrow_hz", 2.0);
     trk_param_fpga.dll_bw_narrow_hz = dll_bw_narrow_hz;
     float dll_bw_hz = configuration->property(role + ".dll_bw_hz", 2.0);
-    if (FLAGS_dll_bw_hz != 0.0) dll_bw_hz = static_cast<float>(FLAGS_dll_bw_hz);
+    if (FLAGS_dll_bw_hz != 0.0)
+        {
+            dll_bw_hz = static_cast<float>(FLAGS_dll_bw_hz);
+        }
     trk_param_fpga.dll_bw_hz = dll_bw_hz;
+
+    int dll_filter_order = configuration->property(role + ".dll_filter_order", 2);
+    if (dll_filter_order < 1)
+        {
+            LOG(WARNING) << "dll_filter_order parameter must be 1, 2 or 3. Set to 1.";
+            dll_filter_order = 1;
+        }
+    if (dll_filter_order > 3)
+        {
+            LOG(WARNING) << "dll_filter_order parameter must be 1, 2 or 3. Set to 3.";
+            dll_filter_order = 3;
+        }
+    trk_param_fpga.dll_filter_order = dll_filter_order;
+
+    int pll_filter_order = configuration->property(role + ".pll_filter_order", 3);
+    if (pll_filter_order < 2)
+        {
+            LOG(WARNING) << "pll_filter_order parameter must be 2 or 3. Set to 2.";
+            pll_filter_order = 2;
+        }
+    if (pll_filter_order > 3)
+        {
+            LOG(WARNING) << "pll_filter_order parameter must be 2 or 3. Set to 3.";
+            pll_filter_order = 3;
+        }
+    trk_param_fpga.pll_filter_order = pll_filter_order;
+
+    if (pll_filter_order == 2)
+        {
+            trk_param_fpga.fll_filter_order = 1;
+        }
+    if (pll_filter_order == 3)
+        {
+            trk_param_fpga.fll_filter_order = 2;
+        }
+
+    bool enable_fll_pull_in = configuration->property(role + ".enable_fll_pull_in", false);
+    trk_param_fpga.enable_fll_pull_in = enable_fll_pull_in;
+    float fll_bw_hz = configuration->property(role + ".fll_bw_hz", 35.0);
+    trk_param_fpga.fll_bw_hz = fll_bw_hz;
+    float pull_in_time_s = configuration->property(role + ".pull_in_time_s", 2.0);
+    trk_param_fpga.pull_in_time_s = pull_in_time_s;
+
     float early_late_space_chips = configuration->property(role + ".early_late_space_chips", 0.5);
     trk_param_fpga.early_late_space_chips = early_late_space_chips;
     float early_late_space_narrow_chips = configuration->property(role + ".early_late_space_narrow_chips", 0.5);
@@ -113,16 +176,28 @@ GpsL1CaDllPllTrackingFpga::GpsL1CaDllPllTrackingFpga(
     char sig_[3] = "1C";
     std::memcpy(trk_param_fpga.signal, sig_, 3);
     int32_t cn0_samples = configuration->property(role + ".cn0_samples", 20);
-    if (FLAGS_cn0_samples != 20) cn0_samples = FLAGS_cn0_samples;
+    if (FLAGS_cn0_samples != 20)
+        {
+            cn0_samples = FLAGS_cn0_samples;
+        }
     trk_param_fpga.cn0_samples = cn0_samples;
-    int32_t cn0_min = configuration->property(role + ".cn0_min", 25);
+    int32_t cn0_min = configuration->property(role + ".cn0_min", 30);
-    if (FLAGS_cn0_min != 25) cn0_min = FLAGS_cn0_min;
+    if (FLAGS_cn0_min != 25)
+        {
+            cn0_min = FLAGS_cn0_min;
+        }
     trk_param_fpga.cn0_min = cn0_min;
     int32_t max_lock_fail = configuration->property(role + ".max_lock_fail", 50);
-    if (FLAGS_max_lock_fail != 50) max_lock_fail = FLAGS_max_lock_fail;
+    if (FLAGS_max_lock_fail != 50)
+        {
+            max_lock_fail = FLAGS_max_lock_fail;
+        }
     trk_param_fpga.max_lock_fail = max_lock_fail;
-    double carrier_lock_th = configuration->property(role + ".carrier_lock_th", 0.85);
+    double carrier_lock_th = configuration->property(role + ".carrier_lock_th", 0.80);
-    if (FLAGS_carrier_lock_th != 0.85) carrier_lock_th = FLAGS_carrier_lock_th;
+    if (FLAGS_carrier_lock_th != 0.85)
+        {
+            carrier_lock_th = FLAGS_carrier_lock_th;
+        }
     trk_param_fpga.carrier_lock_th = carrier_lock_th;
 
     // FPGA configuration parameters
@@ -138,6 +213,18 @@ GpsL1CaDllPllTrackingFpga::GpsL1CaDllPllTrackingFpga(
     for (uint32_t PRN = 1; PRN <= NUM_PRNs; PRN++)
         {
             gps_l1_ca_code_gen_int(&d_ca_codes[(int32_t(GPS_L1_CA_CODE_LENGTH_CHIPS)) * (PRN - 1)], PRN, 0);
+
+            // The code is generated as a series of 1s and -1s. In order to store the values using only one bit, a -1 is stored as a 0 in the FPGA
+            for (uint32_t k = 0; k < GPS_L1_CA_CODE_LENGTH_CHIPS; k++)
+                {
+                    int32_t tmp_value = d_ca_codes[(int32_t(GPS_L1_CA_CODE_LENGTH_CHIPS)) * (PRN - 1) + k];
+                    if (tmp_value < 0)
+                        {
+                            tmp_value = 0;
+                        }
+                    tmp_value = tmp_value | LOCAL_CODE_FPGA_ENABLE_WRITE_MEMORY;
+                    d_ca_codes[(int32_t(GPS_L1_CA_CODE_LENGTH_CHIPS)) * (PRN - 1) + k] = tmp_value;
+                }
         }
     trk_param_fpga.ca_codes = d_ca_codes;
     trk_param_fpga.code_length_chips = GPS_L1_CA_CODE_LENGTH_CHIPS;

src/algorithms/tracking/adapters/gps_l5_dll_pll_tracking_fpga.cc

@@ -50,7 +50,12 @@
 #include <cstring>  // for memcpy
 #include <iostream>
 
-#define NUM_PRNs 32
+#define NUM_PRNs 32  // number of PRNS
+
+// the following flags are FPGA-specific and they are using arrange the values of the local code in the way the FPGA
+// expects. This arrangement is done in the initialisation to avoid consuming unnecessary clock cycles during tracking.
+#define LOCAL_CODE_FPGA_ENABLE_WRITE_MEMORY 0x0C000000      // flag that enables WE (Write Enable) of the local code FPGA
+#define LOCAL_CODE_FPGA_CORRELATOR_SELECT_COUNT 0x20000000  // flag that selects the writing of the pilot code in the FPGA (as opposed to the data code)
 
 
 GpsL5DllPllTrackingFpga::GpsL5DllPllTrackingFpga(
@@ -70,11 +75,27 @@ GpsL5DllPllTrackingFpga::GpsL5DllPllTrackingFpga(
     trk_param_fpga.dump_filename = dump_filename;
     bool dump_mat = configuration->property(role + ".dump_mat", true);
     trk_param_fpga.dump_mat = dump_mat;
+    trk_param_fpga.high_dyn = configuration->property(role + ".high_dyn", false);
+    if (configuration->property(role + ".smoother_length", 10) < 1)
+        {
+            trk_param_fpga.smoother_length = 1;
+            std::cout << TEXT_RED << "WARNING: GPS L5. smoother_length must be bigger than 0. It has been set to 1" << TEXT_RESET << std::endl;
+        }
+    else
+        {
+            trk_param_fpga.smoother_length = configuration->property(role + ".smoother_length", 10);
+        }
     float pll_bw_hz = configuration->property(role + ".pll_bw_hz", 50.0);
-    if (FLAGS_pll_bw_hz != 0.0) pll_bw_hz = static_cast<float>(FLAGS_pll_bw_hz);
+    if (FLAGS_pll_bw_hz != 0.0)
+        {
+            pll_bw_hz = static_cast<float>(FLAGS_pll_bw_hz);
+        }
     trk_param_fpga.pll_bw_hz = pll_bw_hz;
     float dll_bw_hz = configuration->property(role + ".dll_bw_hz", 2.0);
-    if (FLAGS_dll_bw_hz != 0.0) dll_bw_hz = static_cast<float>(FLAGS_dll_bw_hz);
+    if (FLAGS_dll_bw_hz != 0.0)
+        {
+            dll_bw_hz = static_cast<float>(FLAGS_dll_bw_hz);
+        }
     trk_param_fpga.dll_bw_hz = dll_bw_hz;
     float pll_bw_narrow_hz = configuration->property(role + ".pll_bw_narrow_hz", 2.0);
     trk_param_fpga.pll_bw_narrow_hz = pll_bw_narrow_hz;
@@ -82,6 +103,49 @@ GpsL5DllPllTrackingFpga::GpsL5DllPllTrackingFpga(
     trk_param_fpga.dll_bw_narrow_hz = dll_bw_narrow_hz;
     float early_late_space_chips = configuration->property(role + ".early_late_space_chips", 0.5);
     trk_param_fpga.early_late_space_chips = early_late_space_chips;
+
+    int dll_filter_order = configuration->property(role + ".dll_filter_order", 2);
+    if (dll_filter_order < 1)
+        {
+            LOG(WARNING) << "dll_filter_order parameter must be 1, 2 or 3. Set to 1.";
+            dll_filter_order = 1;
+        }
+    if (dll_filter_order > 3)
+        {
+            LOG(WARNING) << "dll_filter_order parameter must be 1, 2 or 3. Set to 3.";
+            dll_filter_order = 3;
+        }
+    trk_param_fpga.dll_filter_order = dll_filter_order;
+
+    int pll_filter_order = configuration->property(role + ".pll_filter_order", 3);
+    if (pll_filter_order < 2)
+        {
+            LOG(WARNING) << "pll_filter_order parameter must be 2 or 3. Set to 2.";
+            pll_filter_order = 2;
+        }
+    if (pll_filter_order > 3)
+        {
+            LOG(WARNING) << "pll_filter_order parameter must be 2 or 3. Set to 3.";
+            pll_filter_order = 3;
+        }
+    trk_param_fpga.pll_filter_order = pll_filter_order;
+
+    if (pll_filter_order == 2)
+        {
+            trk_param_fpga.fll_filter_order = 1;
+        }
+    if (pll_filter_order == 3)
+        {
+            trk_param_fpga.fll_filter_order = 2;
+        }
+
+    bool enable_fll_pull_in = configuration->property(role + ".enable_fll_pull_in", false);
+    trk_param_fpga.enable_fll_pull_in = enable_fll_pull_in;
+    float fll_bw_hz = configuration->property(role + ".fll_bw_hz", 35.0);
+    trk_param_fpga.fll_bw_hz = fll_bw_hz;
+    float pull_in_time_s = configuration->property(role + ".pull_in_time_s", 2.0);
+    trk_param_fpga.pull_in_time_s = pull_in_time_s;
+
     int32_t vector_length = std::round(static_cast<double>(fs_in) / (static_cast<double>(GPS_L5I_CODE_RATE_HZ) / static_cast<double>(GPS_L5I_CODE_LENGTH_CHIPS)));
     trk_param_fpga.vector_length = vector_length;
     int32_t extend_correlation_symbols = configuration->property(role + ".extend_correlation_symbols", 1);
@@ -111,16 +175,28 @@ GpsL5DllPllTrackingFpga::GpsL5DllPllTrackingFpga(
     char sig_[3] = "L5";
     std::memcpy(trk_param_fpga.signal, sig_, 3);
     int32_t cn0_samples = configuration->property(role + ".cn0_samples", 20);
-    if (FLAGS_cn0_samples != 20) cn0_samples = FLAGS_cn0_samples;
+    if (FLAGS_cn0_samples != 20)
+        {
+            cn0_samples = FLAGS_cn0_samples;
+        }
     trk_param_fpga.cn0_samples = cn0_samples;
     int32_t cn0_min = configuration->property(role + ".cn0_min", 25);
-    if (FLAGS_cn0_min != 25) cn0_min = FLAGS_cn0_min;
+    if (FLAGS_cn0_min != 25)
+        {
+            cn0_min = FLAGS_cn0_min;
+        }
     trk_param_fpga.cn0_min = cn0_min;
     int32_t max_lock_fail = configuration->property(role + ".max_lock_fail", 50);
-    if (FLAGS_max_lock_fail != 50) max_lock_fail = FLAGS_max_lock_fail;
+    if (FLAGS_max_lock_fail != 50)
+        {
+            max_lock_fail = FLAGS_max_lock_fail;
+        }
     trk_param_fpga.max_lock_fail = max_lock_fail;
     double carrier_lock_th = configuration->property(role + ".carrier_lock_th", 0.75);
-    if (FLAGS_carrier_lock_th != 0.85) carrier_lock_th = FLAGS_carrier_lock_th;
+    if (FLAGS_carrier_lock_th != 0.85)
+        {
+            carrier_lock_th = FLAGS_carrier_lock_th;
+        }
     trk_param_fpga.carrier_lock_th = carrier_lock_th;
 
     // FPGA configuration parameters
@@ -163,18 +239,40 @@ GpsL5DllPllTrackingFpga::GpsL5DllPllTrackingFpga(
                     gps_l5q_code_gen_float(tracking_code, PRN);
                     gps_l5i_code_gen_float(data_code, PRN);
 
+                    // The code is generated as a series of 1s and -1s. In order to store the values using only one bit, a -1 is stored as a 0 in the FPGA
                     for (uint32_t s = 0; s < code_length_chips; s++)
                         {
-                            d_ca_codes[static_cast<int32_t>(code_length_chips) * (PRN - 1) + s] = static_cast<int32_t>(tracking_code[s]);
+                            int32_t tmp_value = static_cast<int32_t>(tracking_code[s]);
-                            d_data_codes[static_cast<int32_t>(code_length_chips) * (PRN - 1) + s] = static_cast<int32_t>(data_code[s]);
+                            if (tmp_value < 0)
+                                {
+                                    tmp_value = 0;
+                                }
+                            tmp_value = tmp_value | LOCAL_CODE_FPGA_ENABLE_WRITE_MEMORY;
+                            d_ca_codes[static_cast<int32_t>(code_length_chips) * (PRN - 1) + s] = tmp_value;
+
+                            tmp_value = static_cast<int32_t>(data_code[s]);
+                            if (tmp_value < 0)
+                                {
+                                    tmp_value = 0;
+                                }
+                            tmp_value = tmp_value | LOCAL_CODE_FPGA_ENABLE_WRITE_MEMORY | LOCAL_CODE_FPGA_CORRELATOR_SELECT_COUNT;
+                            d_data_codes[static_cast<int32_t>(code_length_chips) * (PRN - 1) + s] = tmp_value;
                         }
                 }
             else
                 {
                     gps_l5i_code_gen_float(tracking_code, PRN);
+
+                    // The code is generated as a series of 1s and -1s. In order to store the values using only one bit, a -1 is stored as a 0 in the FPGA
                     for (uint32_t s = 0; s < code_length_chips; s++)
                         {
-                            d_ca_codes[static_cast<int32_t>(code_length_chips) * (PRN - 1) + s] = static_cast<int32_t>(tracking_code[s]);
+                            int32_t tmp_value = static_cast<int32_t>(tracking_code[s]);
+                            if (tmp_value < 0)
+                                {
+                                    tmp_value = 0;
+                                }
+                            tmp_value = tmp_value | LOCAL_CODE_FPGA_ENABLE_WRITE_MEMORY;
+                            d_ca_codes[static_cast<int32_t>(code_length_chips) * (PRN - 1) + s] = tmp_value;
                         }
                 }
         }

src/algorithms/tracking/gnuradio_blocks/dll_pll_veml_tracking.cc

@@ -560,9 +560,6 @@ void dll_pll_veml_tracking::start_tracking()
     d_carrier_phase_rate_step_rad = 0.0;
     d_carr_ph_history.clear();
     d_code_ph_history.clear();
-    // DLL/PLL filter initialization
-    d_carrier_loop_filter.initialize(static_cast<float>(d_acq_carrier_doppler_hz));  // initialize the carrier filter
-    d_code_loop_filter.initialize();                                                 // initialize the code filter
 
     if (systemName == "GPS" and signal_type == "1C")
         {
@@ -732,8 +729,13 @@ void dll_pll_veml_tracking::start_tracking()
 
     d_current_correlation_time_s = d_code_period;
 
+    // Initialize tracking  ==========================================
+    d_carrier_loop_filter.set_params(trk_parameters.fll_bw_hz, trk_parameters.pll_bw_hz, trk_parameters.pll_filter_order);
     d_code_loop_filter.set_noise_bandwidth(trk_parameters.dll_bw_hz);
     d_code_loop_filter.set_update_interval(d_code_period);
+    // DLL/PLL filter initialization
+    d_carrier_loop_filter.initialize(static_cast<float>(d_acq_carrier_doppler_hz));  // initialize the carrier filter
+    d_code_loop_filter.initialize();                                                 // initialize the code filter
 
     // DEBUG OUTPUT
     std::cout << "Tracking of " << systemName << " " << signal_pretty_name << " signal started on channel " << d_channel << " for satellite " << Gnss_Satellite(systemName, d_acquisition_gnss_synchro->PRN) << std::endl;
@@ -1541,6 +1543,7 @@ void dll_pll_veml_tracking::stop_tracking()
     d_state = 0;
 }
 
+
 int dll_pll_veml_tracking::general_work(int noutput_items __attribute__((unused)), gr_vector_int &ninput_items,
     gr_vector_const_void_star &input_items, gr_vector_void_star &output_items)
 {
@@ -1572,10 +1575,6 @@ int dll_pll_veml_tracking::general_work(int noutput_items __attribute__((unused)
                 double acq_trk_diff_seconds = static_cast<double>(acq_trk_diff_samples) / trk_parameters.fs_in;
                 double delta_trk_to_acq_prn_start_samples = static_cast<double>(acq_trk_diff_samples) - d_acq_code_phase_samples;
 
-                // Doppler effect Fd = (C / (C + Vr)) * F
-                double radial_velocity = (d_signal_carrier_freq + d_acq_carrier_doppler_hz) / d_signal_carrier_freq;
-                // new chip and PRN sequence periods based on acq Doppler
-                d_code_freq_chips = radial_velocity * d_code_chip_rate;
                 d_code_freq_chips = d_code_chip_rate;
                 d_code_phase_step_chips = d_code_freq_chips / trk_parameters.fs_in;
                 d_code_phase_rate_step_chips = 0.0;

src/algorithms/tracking/gnuradio_blocks/dll_pll_veml_tracking_fpga.h

@@ -33,20 +33,20 @@
 #define GNSS_SDR_DLL_PLL_VEML_TRACKING_FPGA_H
 
 #include "dll_pll_conf_fpga.h"
-#include "tracking_2nd_DLL_filter.h"
+#include "tracking_FLL_PLL_filter.h"  // for PLL/FLL filter
-#include "tracking_2nd_PLL_filter.h"
+#include "tracking_loop_filter.h"     // for DLL filter
 #include <boost/circular_buffer.hpp>
-#include <boost/shared_ptr.hpp>
+#include <boost/shared_ptr.hpp>   // for boost::shared_ptr
-#include <gnuradio/block.h>
+#include <gnuradio/block.h>       // for block
 #include <gnuradio/gr_complex.h>  // for gr_complex
-#include <gnuradio/types.h>       // for gr_vector_const_void_star
+#include <gnuradio/types.h>       // for gr_vector_int, gr_vector...
 #include <pmt/pmt.h>              // for pmt_t
-#include <cstdint>
+#include <cstdint>                // for int32_t
-#include <deque>    // for deque
+#include <deque>                  // for deque
-#include <fstream>  // for ofstream
+#include <fstream>                // for string, ofstream
-#include <memory>   // for shared_ptr
+#include <memory>                 // for shared_ptr
 #include <string>
-#include <utility>
+#include <utility>  // for pair
 
 class Fpga_Multicorrelator_8sc;
 class Gnss_Synchro;
@@ -77,7 +77,7 @@ public:
 
 private:
     friend dll_pll_veml_tracking_fpga_sptr dll_pll_veml_make_tracking_fpga(const Dll_Pll_Conf_Fpga &conf_);
-
+    void msg_handler_telemetry_to_trk(const pmt::pmt_t &msg);
     dll_pll_veml_tracking_fpga(const Dll_Pll_Conf_Fpga &conf_);
     void msg_handler_preamble_index(pmt::pmt_t msg);
 
@@ -91,7 +91,7 @@ private:
     void log_data(bool integrating);
     int32_t save_matfile();
 
-    void run_state_2(Gnss_Synchro &current_synchro_data);
+    //void run_state_2(Gnss_Synchro &current_synchro_data);
 
     // tracking configuration vars
     Dll_Pll_Conf_Fpga trk_parameters;
@@ -115,23 +115,20 @@ private:
     std::string *d_secondary_code_string;
     std::string signal_pretty_name;
 
-    int32_t *d_gps_l1ca_preambles_symbols;
+    int32_t *d_preambles_symbols;
+    int32_t d_preamble_length_symbols;
     boost::circular_buffer<float> d_symbol_history;
 
-    //tracking state machine
+    // tracking state machine
     int32_t d_state;
-    //Integration period in samples
+
+    // Integration period in samples
     int32_t d_correlation_length_ms;
     int32_t d_n_correlator_taps;
 
     float *d_local_code_shift_chips;
     float *d_prompt_data_shift;
     std::shared_ptr<Fpga_Multicorrelator_8sc> multicorrelator_fpga;
-    /*  TODO: currently the multicorrelator does not support adding extra correlator
-        with different local code, thus we need extra multicorrelator instance.
-        Implement this functionality inside multicorrelator class
-        as an enhancement to increase the performance
-     */
     gr_complex *d_correlator_outs;
     gr_complex *d_Very_Early;
     gr_complex *d_Early;
@@ -146,9 +143,9 @@ private:
     gr_complex d_VE_accu;
     gr_complex d_E_accu;
     gr_complex d_P_accu;
+    gr_complex d_P_accu_old;
     gr_complex d_L_accu;
     gr_complex d_VL_accu;
-    gr_complex d_last_prompt;
 
     gr_complex *d_Prompt_Data;
 
@@ -163,15 +160,18 @@ private:
     float d_rem_carr_phase_rad;
 
     // PLL and DLL filter library
-    Tracking_2nd_DLL_filter d_code_loop_filter;
+    Tracking_loop_filter d_code_loop_filter;
-    Tracking_2nd_PLL_filter d_carrier_loop_filter;
+    Tracking_FLL_PLL_filter d_carrier_loop_filter;
 
     // acquisition
     double d_acq_code_phase_samples;
     double d_acq_carrier_doppler_hz;
 
     // tracking vars
-    double d_carr_error_hz;
+    bool d_pull_in_transitory;
+    double d_current_correlation_time_s;
+    double d_carr_phase_error_hz;
+    double d_carr_freq_error_hz;
     double d_carr_error_filt_hz;
     double d_code_error_chips;
     double d_code_error_filt_chips;
@@ -194,11 +194,12 @@ private:
     // CN0 estimation and lock detector
     int32_t d_cn0_estimation_counter;
     int32_t d_carrier_lock_fail_counter;
-    std::deque<float> d_carrier_lock_detector_queue;
+    //std::deque<float> d_carrier_lock_detector_queue;
     double d_carrier_lock_test;
     double d_CN0_SNV_dB_Hz;
     double d_carrier_lock_threshold;
-    std::deque<gr_complex> d_Prompt_buffer_deque;
+    boost::circular_buffer<gr_complex> d_Prompt_circular_buffer;
+    //std::deque<gr_complex> d_Prompt_buffer_deque;
     gr_complex *d_Prompt_buffer;
 
     // file dump

src/algorithms/tracking/libs/dll_pll_conf_fpga.cc

@@ -44,6 +44,15 @@ Dll_Pll_Conf_Fpga::Dll_Pll_Conf_Fpga()
     dump = false;
     dump_mat = true;
     dump_filename = std::string("./dll_pll_dump.dat");
+    enable_fll_pull_in = false;
+    enable_fll_steady_state = false;
+    pull_in_time_s = 2;
+    fll_filter_order = 1;
+    pll_filter_order = 3;
+    dll_filter_order = 2;
+    fll_bw_hz = 35.0;
+    pll_pull_in_bw_hz = 50.0;
+    dll_pull_in_bw_hz = 3.0;
     pll_bw_hz = 35.0;
     dll_bw_hz = 2.0;
     pll_bw_narrow_hz = 5.0;

src/algorithms/tracking/libs/dll_pll_conf_fpga.h

@@ -42,11 +42,22 @@ class Dll_Pll_Conf_Fpga
 {
 public:
     /* DLL/PLL tracking configuration */
+    int fll_filter_order;
+    bool enable_fll_pull_in;
+    bool enable_fll_steady_state;
+    unsigned int pull_in_time_s;  // signed integer, when pull in time is not yet reached it has to be compared against a negative number
+    int pll_filter_order;
+    int dll_filter_order;
+
+
     double fs_in;
     uint32_t vector_length;
     bool dump;
     bool dump_mat;
     std::string dump_filename;
+    float pll_pull_in_bw_hz;
+    float dll_pull_in_bw_hz;
+    float fll_bw_hz;
     float pll_bw_hz;
     float dll_bw_hz;
     float pll_bw_narrow_hz;

src/algorithms/tracking/libs/fpga_multicorrelator.cc

@@ -51,14 +51,15 @@
 #define CODE_PHASE_STEP_CHIPS_NUM_NBITS CODE_RESAMPLER_NUM_BITS_PRECISION
 #define pwrtwo(x) (1 << (x))
 #define MAX_CODE_RESAMPLER_COUNTER pwrtwo(CODE_PHASE_STEP_CHIPS_NUM_NBITS)  // 2^CODE_PHASE_STEP_CHIPS_NUM_NBITS
-#define PHASE_CARR_NBITS 32
+#define PHASE_CARR_MAX 2147483648                                           // 2^(31) The phase is represented as a 32-bit vector in 1.31 format
-#define PHASE_CARR_NBITS_INT 1
+#define PHASE_CARR_MAX_div_PI 683565275.5764316                             // 2^(31)/pi
-#define PHASE_CARR_NBITS_FRAC PHASE_CARR_NBITS - PHASE_CARR_NBITS_INT
+#define TWO_PI 6.283185307179586
 #define LOCAL_CODE_FPGA_CORRELATOR_SELECT_COUNT 0x20000000
 #define LOCAL_CODE_FPGA_CLEAR_ADDRESS_COUNTER 0x10000000
 #define LOCAL_CODE_FPGA_ENABLE_WRITE_MEMORY 0x0C000000
 #define TEST_REGISTER_TRACK_WRITEVAL 0x55AA
-
+#define ENABLE_TRK_INT_ON_RESET 1 /* flag that causes the tracking HW accelerator to trigger an interrupt when it is reset. It is used \
+                          to avoid a potential deadlock caused by the SW waiting for an interrupt from the FPGA when the HW is reset */
 #ifndef TEMP_FAILURE_RETRY
 #define TEMP_FAILURE_RETRY(exp)              \
     ({                                       \
@@ -118,6 +119,7 @@ Fpga_Multicorrelator_8sc::Fpga_Multicorrelator_8sc(int32_t n_correlators,
     d_data_codes = data_codes;
     d_multicorr_type = multicorr_type;
     d_code_samples_per_chip = code_samples_per_chip;
+    d_code_length_samples = d_code_length_chips * d_code_samples_per_chip;
 
     DLOG(INFO) << "TRACKING FPGA CLASS CREATED";
 }
@@ -171,28 +173,30 @@ void Fpga_Multicorrelator_8sc::set_output_vectors(gr_complex *corr_out, gr_compl
 }
 
 
-void Fpga_Multicorrelator_8sc::update_local_code(float rem_code_phase_chips)
+void Fpga_Multicorrelator_8sc::update_local_code()
 {
-    d_rem_code_phase_chips = rem_code_phase_chips;
     Fpga_Multicorrelator_8sc::fpga_compute_code_shift_parameters();
     Fpga_Multicorrelator_8sc::fpga_configure_code_parameters_in_fpga();
 }
 
 
 void Fpga_Multicorrelator_8sc::Carrier_wipeoff_multicorrelator_resampler(
-    float rem_carrier_phase_in_rad,
+    float rem_carrier_phase_in_rad,                             // nco phase initial position
-    float phase_step_rad,
+    float phase_step_rad,                                       // nco phase step
-    float carrier_phase_rate_step_rad __attribute__((unused)),
+    float carrier_phase_rate_step_rad __attribute__((unused)),  // nco phase step rate change
-    float rem_code_phase_chips,
+    float rem_code_phase_chips,                                 // code resampler initial position
-    float code_phase_step_chips __attribute__((unused)),
+    float code_phase_step_chips __attribute__((unused)),        // code resampler step
-    float code_phase_rate_step_chips __attribute__((unused)),
+    float code_phase_rate_step_chips __attribute__((unused)),   // code resampler step rate
-    int32_t signal_length_samples)
+    int32_t signal_length_samples)                              // number of samples
 {
-    update_local_code(rem_code_phase_chips);
+    d_rem_carrier_phase_in_rad = rem_carrier_phase_in_rad;        // nco phase initial position
-    d_rem_carrier_phase_in_rad = rem_carrier_phase_in_rad;
+    d_phase_step_rad = phase_step_rad;                            // nco phase step
-    d_code_phase_step_chips = code_phase_step_chips;
+    d_carrier_phase_rate_step_rad = carrier_phase_rate_step_rad;  // nco phase step rate
-    d_phase_step_rad = phase_step_rad;
+    d_rem_code_phase_chips = rem_code_phase_chips;                // code resampler initial position
-    d_correlator_length_samples = signal_length_samples;
+    d_code_phase_step_chips = code_phase_step_chips;              // code resampler step
+    d_code_phase_rate_step_chips = code_phase_rate_step_chips;    // code resampler step rate
+    d_correlator_length_samples = signal_length_samples;          // number of samples
+    Fpga_Multicorrelator_8sc::update_local_code();
     Fpga_Multicorrelator_8sc::fpga_compute_signal_parameters_in_fpga();
     Fpga_Multicorrelator_8sc::fpga_configure_signal_parameters_in_fpga();
     Fpga_Multicorrelator_8sc::fpga_launch_multicorrelator_fpga();
@@ -279,6 +283,16 @@ void Fpga_Multicorrelator_8sc::set_channel(uint32_t channel)
         {
             LOG(INFO) << "Test register sanity check success !";
         }
+
+    d_map_base[INT_ON_RST_REG_ADDR] = ENABLE_TRK_INT_ON_RESET;  // enable interrupts on reset to prevent deadlock
+
+    // enable interrupts
+    int32_t reenable = 1;
+    ssize_t nbytes = TEMP_FAILURE_RETRY(write(d_device_descriptor, reinterpret_cast<void *>(&reenable), sizeof(int32_t)));
+    if (nbytes != sizeof(int32_t))
+        {
+            std::cerr << "Error launching the FPGA multicorrelator" << std::endl;
+        }
 }
 
 
@@ -298,88 +312,72 @@ uint32_t Fpga_Multicorrelator_8sc::fpga_acquisition_test_register(
 void Fpga_Multicorrelator_8sc::fpga_configure_tracking_gps_local_code(int32_t PRN)
 {
     uint32_t k;
-    uint32_t code_chip;
-    uint32_t select_pilot_corelator = LOCAL_CODE_FPGA_CORRELATOR_SELECT_COUNT;
 
     d_map_base[PROG_MEMS_ADDR] = LOCAL_CODE_FPGA_CLEAR_ADDRESS_COUNTER;
-    for (k = 0; k < d_code_length_chips * d_code_samples_per_chip; k++)
+    for (k = 0; k < d_code_length_samples; k++)
         {
-            if (d_ca_codes[((int32_t(d_code_length_chips)) * d_code_samples_per_chip * (PRN - 1)) + k] == 1)
+            d_map_base[PROG_MEMS_ADDR] = d_ca_codes[(d_code_length_samples * (PRN - 1)) + k];
-                {
-                    code_chip = 1;
-                }
-            else
-                {
-                    code_chip = 0;
-                }
-
-            // copy the local code to the FPGA memory one by one
-            d_map_base[PROG_MEMS_ADDR] = LOCAL_CODE_FPGA_ENABLE_WRITE_MEMORY | code_chip;  // | select_fpga_correlator;
         }
     if (d_track_pilot)
         {
             d_map_base[PROG_MEMS_ADDR] = LOCAL_CODE_FPGA_CLEAR_ADDRESS_COUNTER;
-            for (k = 0; k < d_code_length_chips * d_code_samples_per_chip; k++)
+            for (k = 0; k < d_code_length_samples; k++)
                 {
-                    if (d_data_codes[((int32_t(d_code_length_chips)) * d_code_samples_per_chip * (PRN - 1)) + k] == 1)
+                    d_map_base[PROG_MEMS_ADDR] = d_data_codes[(d_code_length_samples * (PRN - 1)) + k];
-                        {
-                            code_chip = 1;
-                        }
-                    else
-                        {
-                            code_chip = 0;
-                        }
-                    d_map_base[PROG_MEMS_ADDR] = LOCAL_CODE_FPGA_ENABLE_WRITE_MEMORY | code_chip | select_pilot_corelator;
                 }
         }
+
+    d_map_base[CODE_LENGTH_MINUS_1_REG_ADDR] = (d_code_length_samples)-1;  // number of samples - 1
 }
 
 
 void Fpga_Multicorrelator_8sc::fpga_compute_code_shift_parameters(void)
 {
-    float temp_calculation;
+    float frac_part;   // decimal part
-    int32_t i;
+    int32_t dec_part;  // fractional part
 
-    for (i = 0; i < d_n_correlators; i++)
+    for (uint32_t i = 0; i < d_n_correlators; i++)
         {
-            temp_calculation = floor(d_shifts_chips[i] - d_rem_code_phase_chips);
+            dec_part = floor(d_shifts_chips[i] - d_rem_code_phase_chips);
 
-            if (temp_calculation < 0)
+            if (dec_part < 0)
                 {
-                    temp_calculation = temp_calculation + (d_code_length_chips * d_code_samples_per_chip);  // % operator does not work as in Matlab with negative numbers
+                    dec_part = dec_part + d_code_length_samples;  // % operator does not work as in Matlab with negative numbers
                 }
-            d_initial_index[i] = static_cast<uint32_t>((static_cast<int32_t>(temp_calculation)) % (d_code_length_chips * d_code_samples_per_chip));
+            d_initial_index[i] = dec_part;
-            temp_calculation = fmod(d_shifts_chips[i] - d_rem_code_phase_chips, 1.0);
+
-            if (temp_calculation < 0)
+
+            frac_part = fmod(d_shifts_chips[i] - d_rem_code_phase_chips, 1.0);
+            if (frac_part < 0)
                 {
-                    temp_calculation = temp_calculation + 1.0;  // fmod operator does not work as in Matlab with negative numbers
+                    frac_part = frac_part + 1.0;  // fmod operator does not work as in Matlab with negative numbers
                 }
 
-            d_initial_interp_counter[i] = static_cast<uint32_t>(floor(MAX_CODE_RESAMPLER_COUNTER * temp_calculation));
+            d_initial_interp_counter[i] = static_cast<uint32_t>(floor(MAX_CODE_RESAMPLER_COUNTER * frac_part));
         }
     if (d_track_pilot)
         {
-            temp_calculation = floor(d_prompt_data_shift[0] - d_rem_code_phase_chips);
+            dec_part = floor(d_prompt_data_shift[0] - d_rem_code_phase_chips);
 
-            if (temp_calculation < 0)
+            if (dec_part < 0)
                 {
-                    temp_calculation = temp_calculation + (d_code_length_chips * d_code_samples_per_chip);  // % operator does not work as in Matlab with negative numbers
+                    dec_part = dec_part + d_code_length_samples;  // % operator does not work as in Matlab with negative numbers
                 }
-            d_initial_index[d_n_correlators] = static_cast<uint32_t>((static_cast<int32_t>(temp_calculation)) % (d_code_length_chips * d_code_samples_per_chip));
+            d_initial_index[d_n_correlators] = dec_part;
-            temp_calculation = fmod(d_prompt_data_shift[0] - d_rem_code_phase_chips, 1.0);
+
-            if (temp_calculation < 0)
+            frac_part = fmod(d_prompt_data_shift[0] - d_rem_code_phase_chips, 1.0);
+            if (frac_part < 0)
                 {
-                    temp_calculation = temp_calculation + 1.0;  // fmod operator does not work as in Matlab with negative numbers
+                    frac_part = frac_part + 1.0;  // fmod operator does not work as in Matlab with negative numbers
                 }
-            d_initial_interp_counter[d_n_correlators] = static_cast<uint32_t>(floor(MAX_CODE_RESAMPLER_COUNTER * temp_calculation));
+            d_initial_interp_counter[d_n_correlators] = static_cast<uint32_t>(floor(MAX_CODE_RESAMPLER_COUNTER * frac_part));
         }
 }
 
 
 void Fpga_Multicorrelator_8sc::fpga_configure_code_parameters_in_fpga(void)
 {
-    int32_t i;
+    for (uint32_t i = 0; i < d_n_correlators; i++)
-    for (i = 0; i < d_n_correlators; i++)
         {
             d_map_base[INITIAL_INDEX_REG_BASE_ADDR + i] = d_initial_index[i];
             d_map_base[INITIAL_INTERP_COUNTER_REG_BASE_ADDR + i] = d_initial_interp_counter[i];
@@ -389,8 +387,6 @@ void Fpga_Multicorrelator_8sc::fpga_configure_code_parameters_in_fpga(void)
             d_map_base[INITIAL_INDEX_REG_BASE_ADDR + d_n_correlators] = d_initial_index[d_n_correlators];
             d_map_base[INITIAL_INTERP_COUNTER_REG_BASE_ADDR + d_n_correlators] = d_initial_interp_counter[d_n_correlators];
         }
-
-    d_map_base[CODE_LENGTH_MINUS_1_REG_ADDR] = (d_code_length_chips * d_code_samples_per_chip) - 1;  // number of samples - 1
 }
 
 
@@ -399,58 +395,52 @@ void Fpga_Multicorrelator_8sc::fpga_compute_signal_parameters_in_fpga(void)
     float d_rem_carrier_phase_in_rad_temp;
 
     d_code_phase_step_chips_num = static_cast<uint32_t>(roundf(MAX_CODE_RESAMPLER_COUNTER * d_code_phase_step_chips));
-    if (d_code_phase_step_chips > 1.0)
+    d_code_phase_rate_step_chips_num = static_cast<uint32_t>(roundf(MAX_CODE_RESAMPLER_COUNTER * d_code_phase_rate_step_chips));
-        {
-            std::cout << "Warning : d_code_phase_step_chips = " << d_code_phase_step_chips << " cannot be bigger than one" << std::endl;
-        }
 
     if (d_rem_carrier_phase_in_rad > M_PI)
         {
-            d_rem_carrier_phase_in_rad_temp = -2 * M_PI + d_rem_carrier_phase_in_rad;
+            d_rem_carrier_phase_in_rad_temp = -TWO_PI + d_rem_carrier_phase_in_rad;
         }
     else if (d_rem_carrier_phase_in_rad < -M_PI)
         {
-            d_rem_carrier_phase_in_rad_temp = 2 * M_PI + d_rem_carrier_phase_in_rad;
+            d_rem_carrier_phase_in_rad_temp = TWO_PI + d_rem_carrier_phase_in_rad;
         }
     else
         {
             d_rem_carrier_phase_in_rad_temp = d_rem_carrier_phase_in_rad;
         }
-    d_rem_carr_phase_rad_int = static_cast<int32_t>(roundf((fabs(d_rem_carrier_phase_in_rad_temp) / M_PI) * pow(2, PHASE_CARR_NBITS_FRAC)));
-    if (d_rem_carrier_phase_in_rad_temp < 0)
-        {
-            d_rem_carr_phase_rad_int = -d_rem_carr_phase_rad_int;
-        }
-    d_phase_step_rad_int = static_cast<int32_t>(roundf((fabs(d_phase_step_rad) / M_PI) * pow(2, PHASE_CARR_NBITS_FRAC)));  // the FPGA accepts a range for the phase step between -pi and +pi
 
-    if (d_phase_step_rad < 0)
+    d_rem_carr_phase_rad_int = static_cast<int32_t>(roundf((d_rem_carrier_phase_in_rad_temp)*PHASE_CARR_MAX_div_PI));
-        {
+    d_phase_step_rad_int = static_cast<int32_t>(roundf((d_phase_step_rad)*PHASE_CARR_MAX_div_PI));  // the FPGA accepts a range for the phase step between -pi and +pi
-            d_phase_step_rad_int = -d_phase_step_rad_int;
+    d_carrier_phase_rate_step_rad_int = static_cast<int32_t>(roundf((d_carrier_phase_rate_step_rad)*PHASE_CARR_MAX_div_PI));
-        }
 }
 
 
 void Fpga_Multicorrelator_8sc::fpga_configure_signal_parameters_in_fpga(void)
 {
-    d_map_base[CODE_PHASE_STEP_CHIPS_NUM_REG_ADDR] = d_code_phase_step_chips_num;
+    d_map_base[CODE_PHASE_STEP_CHIPS_NUM_REG_ADDR] = d_code_phase_step_chips_num;  // code phase step
 
-    d_map_base[NSAMPLES_MINUS_1_REG_ADDR] = d_correlator_length_samples - 1;
+    d_map_base[CODE_PHASE_STEP_CHIPS_RATE] = d_code_phase_rate_step_chips_num;  // code phase step rate
 
-    d_map_base[REM_CARR_PHASE_RAD_REG_ADDR] = d_rem_carr_phase_rad_int;
+    d_map_base[NSAMPLES_MINUS_1_REG_ADDR] = d_correlator_length_samples - 1;  // number of samples
 
-    d_map_base[PHASE_STEP_RAD_REG_ADDR] = d_phase_step_rad_int;
+    d_map_base[REM_CARR_PHASE_RAD_REG_ADDR] = d_rem_carr_phase_rad_int;  // initial nco phase
+
+    d_map_base[PHASE_STEP_RAD_REG_ADDR] = d_phase_step_rad_int;  // nco phase step
+
+    d_map_base[PHASE_STEP_RATE_REG_ADDR] = d_carrier_phase_rate_step_rad_int;  // nco phase step rate
 }
 
 
 void Fpga_Multicorrelator_8sc::fpga_launch_multicorrelator_fpga(void)
 {
-    // enable interrupts
+    //    // enable interrupts
-    int32_t reenable = 1;
+    //    int32_t reenable = 1;
-    ssize_t nbytes = TEMP_FAILURE_RETRY(write(d_device_descriptor, reinterpret_cast<void *>(&reenable), sizeof(int32_t)));
+    //    ssize_t nbytes = TEMP_FAILURE_RETRY(write(d_device_descriptor, reinterpret_cast<void *>(&reenable), sizeof(int32_t)));
-    if (nbytes != sizeof(int32_t))
+    //    if (nbytes != sizeof(int32_t))
-        {
+    //        {
-            std::cerr << "Error launching the FPGA multicorrelator" << std::endl;
+    //            std::cerr << "Error launching the FPGA multicorrelator" << std::endl;
-        }
+    //        }
     // writing 1 to reg 14 launches the tracking
     d_map_base[START_FLAG_ADDR] = 1;
 }
@@ -460,9 +450,8 @@ void Fpga_Multicorrelator_8sc::read_tracking_gps_results(void)
 {
     int32_t readval_real;
     int32_t readval_imag;
-    int32_t k;
 
-    for (k = 0; k < d_n_correlators; k++)
+    for (uint32_t k = 0; k < d_n_correlators; k++)
         {
             readval_real = d_map_base[RESULT_REG_REAL_BASE_ADDR + k];
             readval_imag = d_map_base[RESULT_REG_IMAG_BASE_ADDR + k];

src/algorithms/tracking/libs/fpga_multicorrelator.h

@@ -54,7 +54,10 @@
 #define DROP_SAMPLES_REG_ADDR 18
 #define INITIAL_COUNTER_VALUE_REG_ADDR_LSW 19
 #define INITIAL_COUNTER_VALUE_REG_ADDR_MSW 20
+#define CODE_PHASE_STEP_CHIPS_RATE 21
+#define PHASE_STEP_RATE_REG_ADDR 22
 #define STOP_TRACKING_REG_ADDR 23
+#define INT_ON_RST_REG_ADDR 24  // cause interrupt on reset to prevent deadlock
 #define START_FLAG_ADDR 30
 // read-write addresses
 #define TEST_REG_ADDR 31
@@ -77,7 +80,7 @@ public:
     void set_output_vectors(gr_complex *corr_out, gr_complex *Prompt_Data);
     void set_local_code_and_taps(
         float *shifts_chips, float *prompt_data_shift, int32_t PRN);
-    void update_local_code(float rem_code_phase_chips);
+    void update_local_code();
     void Carrier_wipeoff_multicorrelator_resampler(
         float rem_carrier_phase_in_rad, float phase_step_rad,
         float carrier_phase_rate_step_rad,
@@ -96,27 +99,32 @@ private:
     gr_complex *d_Prompt_Data;
     float *d_shifts_chips;
     float *d_prompt_data_shift;
-    int32_t d_code_length_chips;
+    uint32_t d_code_length_chips;
-    int32_t d_n_correlators; // number of correlators
+    uint32_t d_code_length_samples;
+    uint32_t d_n_correlators;  // number of correlators
 
     // data related to the hardware module and the driver
     int32_t d_device_descriptor;    // driver descriptor
     volatile uint32_t *d_map_base;  // driver memory map
 
     // configuration data received from the interface
-    uint32_t d_channel;       // channel number
+    uint32_t d_channel;  // channel number
     uint32_t d_correlator_length_samples;
     float d_rem_code_phase_chips;
     float d_code_phase_step_chips;
+    float d_code_phase_rate_step_chips;
     float d_rem_carrier_phase_in_rad;
     float d_phase_step_rad;
+    float d_carrier_phase_rate_step_rad;
 
     // configuration data computed in the format that the FPGA expects
     uint32_t *d_initial_index;
     uint32_t *d_initial_interp_counter;
     uint32_t d_code_phase_step_chips_num;
+    uint32_t d_code_phase_rate_step_chips_num;
     int32_t d_rem_carr_phase_rad_int;
     int32_t d_phase_step_rad_int;
+    int32_t d_carrier_phase_rate_step_rad_int;
     uint64_t d_initial_sample_counter;
 
     // driver

src/core/interfaces/acquisition_interface.h

@@ -58,7 +58,7 @@ class AcquisitionInterface : public GNSSBlockInterface
 public:
     virtual void set_gnss_synchro(Gnss_Synchro* gnss_synchro) = 0;
     virtual void set_channel(unsigned int channel_id) = 0;
-    virtual void set_channel_fsm(std::shared_ptr<ChannelFsm> channel_fsm) = 0;
+    virtual void set_channel_fsm(std::weak_ptr<ChannelFsm> channel_fsm) = 0;
     virtual void set_threshold(float threshold) = 0;
     virtual void set_doppler_max(unsigned int doppler_max) = 0;
     virtual void set_doppler_step(unsigned int doppler_step) = 0;

src/core/libs/gnss_sdr_fpga_sample_counter.cc

@@ -2,11 +2,12 @@
  * \file gnss_sdr_fpga_sample_counter.cc
  * \brief Simple block to report the current receiver time based on the output
  * of the tracking or telemetry blocks
+ * \author Marc Majoral 2019. mmajoral(at)cttc.es
  * \author Javier Arribas 2018. jarribas(at)cttc.es
  *
  * -------------------------------------------------------------------------
  *
- * Copyright (C) 2010-2018  (see AUTHORS file for a list of contributors)
+ * Copyright (C) 2010-2019  (see AUTHORS file for a list of contributors)
  *
  * GNSS-SDR is a software defined Global Navigation
  *          Satellite Systems receiver
@@ -69,19 +70,17 @@ gnss_sdr_fpga_sample_counter::gnss_sdr_fpga_sample_counter(
     interval_ms = _interval_ms;
     fs = _fs;
     samples_per_output = std::round(fs * static_cast<double>(interval_ms) / 1e3);
-    //todo: Load here the hardware counter register with this amount of samples. It should produce an
-    //interrupt every samples_per_output count.
-    //The hardware timer must keep always interrupting the PS. It must not wait for the interrupt to
-    //be served.
     open_device();
     is_open = true;
     sample_counter = 0ULL;
+    last_sample_counter = 0ULL;
     current_T_rx_ms = 0;
     current_s = 0;
     current_m = 0;
     current_h = 0;
     current_days = 0;
-    report_interval_ms = 1000;     // default reporting 1 second
+    report_interval_ms = 1000;  // default reporting 1 second
+    samples_per_report = std::round(fs * static_cast<double>(report_interval_ms) / 1e3);
     flag_enable_send_msg = false;  // enable it for reporting time with asynchronous message
     flag_m = false;
     flag_h = false;
@@ -105,11 +104,9 @@ gnss_sdr_fpga_sample_counter::~gnss_sdr_fpga_sample_counter()
 }
 
 
-// Called by gnuradio to enable drivers, etc for i/o devices.
+// Called by GNU Radio to enable drivers, etc for i/o devices.
 bool gnss_sdr_fpga_sample_counter::start()
 {
-    //todo: place here the RE-INITIALIZATION routines. This function will be called by GNURadio at every start of the flowgraph.
-
     // configure the number of samples per output in the FPGA and enable the interrupts
     configure_samples_per_output(samples_per_output);
 
@@ -118,11 +115,9 @@ bool gnss_sdr_fpga_sample_counter::start()
 }
 
 
-// Called by GNURadio to disable drivers, etc for i/o devices.
+// Called by GNU Radio to disable drivers, etc for i/o devices.
 bool gnss_sdr_fpga_sample_counter::stop()
 {
-    //todo: place here the routines to stop the associated hardware (if needed).This function will be called by GNURadio at every stop of the flowgraph.
-    // return true if everything is ok.
     close_device();
     is_open = false;
     return true;
@@ -194,65 +189,31 @@ void gnss_sdr_fpga_sample_counter::close_device()
 }
 
 
-uint32_t gnss_sdr_fpga_sample_counter::wait_for_interrupt_and_read_counter()
-{
-    int32_t irq_count;
-    ssize_t nb;
-    int32_t counter;
-
-    // enable interrupts
-    int32_t reenable = 1;
-    ssize_t nbytes = TEMP_FAILURE_RETRY(write(fd, reinterpret_cast<void *>(&reenable), sizeof(int32_t)));
-    if (nbytes != sizeof(int32_t))
-        {
-            std::cerr << "Error enabling interruptions in the FPGA." << std::endl;
-        }
-
-    // wait for interrupt
-    nb = read(fd, &irq_count, sizeof(irq_count));
-    if (nb != sizeof(irq_count))
-        {
-            std::cout << "FPGA sample counter module read failed to retrieve 4 bytes!" << std::endl;
-            std::cout << "FPGA sample counter module interrupt number " << irq_count << std::endl;
-        }
-
-    // it is a rising edge interrupt, the interrupt does not need to be acknowledged
-    //map_base[1] = 0; // writing anything to reg 1 acknowledges the interrupt
-
-    // add number of passed samples or read the current counter value for more accuracy
-    counter = samples_per_output;  //map_base[0];
-    return counter;
-}
-
-
 int gnss_sdr_fpga_sample_counter::general_work(int noutput_items __attribute__((unused)),
     __attribute__((unused)) gr_vector_int &ninput_items,
     __attribute__((unused)) gr_vector_const_void_star &input_items,
     gr_vector_void_star &output_items)
 {
-    //todo: Call here a function that waits for an interrupt. Do not open a thread,
+    wait_for_interrupt();
-    //it must be a simple call to a BLOCKING function.
-    // The function will return the actual absolute sample count of the internal counter of the timmer.
-    // store the sample count in class member sample_counter
-    // Possible problem: what happen if the PS is overloaded and gnuradio does not call this function
-    // with the sufficient rate to catch all the interrupts in the counter. To be evaluated later.
 
-    uint32_t counter = wait_for_interrupt_and_read_counter();
+    uint64_t sample_counter_tmp, sample_counter_msw_tmp;
-    uint64_t samples_passed = 2 * static_cast<uint64_t>(samples_per_output) - static_cast<uint64_t>(counter);  // ellapsed samples
+    sample_counter_tmp = map_base[0];
-    // Note: at this moment the sample counter is implemented as a sample counter that decreases to zero and then it is automatically
+    sample_counter_msw_tmp = map_base[1];
-    // reloaded again and keeps counter. It is done in this way to minimize the logic in the FPGA and maximize the FPGA clock performance
+    sample_counter_msw_tmp = sample_counter_msw_tmp << 32;
-    // (it takes less resources and latency in the FPGA to compare a number against a fixed value like zero than to compare it to a programmable
+    sample_counter_tmp = sample_counter_tmp + sample_counter_msw_tmp;  // 2^32
-    // variable number).
+    sample_counter = sample_counter_tmp;
 
-    sample_counter = sample_counter + samples_passed;  //samples_per_output;
     auto *out = reinterpret_cast<Gnss_Synchro *>(output_items[0]);
     out[0] = Gnss_Synchro();
     out[0].Flag_valid_symbol_output = false;
     out[0].Flag_valid_word = false;
     out[0].Channel_ID = -1;
     out[0].fs = fs;
-    if ((current_T_rx_ms % report_interval_ms) == 0)
+
+    if ((sample_counter - last_sample_counter) > samples_per_report)
         {
+            last_sample_counter = sample_counter;
+
             current_s++;
             if ((current_s % 60) == 0)
                 {
@@ -310,7 +271,25 @@ int gnss_sdr_fpga_sample_counter::general_work(int noutput_items __attribute__((
                 }
         }
     out[0].Tracking_sample_counter = sample_counter;
-    //current_T_rx_ms = (sample_counter * 1000) / samples_per_output;
     current_T_rx_ms = interval_ms * (sample_counter) / samples_per_output;
     return 1;
 }
+
+
+void gnss_sdr_fpga_sample_counter::wait_for_interrupt()
+{
+    int32_t irq_count;
+    ssize_t nb;
+
+    // enable interrupts
+    int32_t reenable = 1;
+    write(fd, reinterpret_cast<void *>(&reenable), sizeof(int32_t));
+
+    // wait for interrupt
+    nb = read(fd, &irq_count, sizeof(irq_count));
+    if (nb != sizeof(irq_count))
+        {
+            std::cout << "fpga sample counter module read failed to retrieve 4 bytes!" << std::endl;
+            std::cout << "fpga sample counter module interrupt number " << irq_count << std::endl;
+        }
+}

src/core/libs/gnss_sdr_fpga_sample_counter.h

@@ -55,11 +55,15 @@ private:
     void close_device(void);
     void open_device(void);
     bool start();
+
     bool stop();
-    uint32_t wait_for_interrupt_and_read_counter(void);
+    void wait_for_interrupt(void);
     uint32_t samples_per_output;
+    uint32_t samples_per_report;
     double fs;
     uint64_t sample_counter;
+    uint64_t last_sample_counter;
+
     uint32_t interval_ms;
     uint64_t current_T_rx_ms;  // Receiver time in ms since the beginning of the run
     uint32_t current_s;        // Receiver time in seconds, modulo 60
@@ -70,6 +74,7 @@ private:
     bool flag_days;            // True if the receiver has been running for at least 1 day
     uint32_t current_days;     // Receiver time in days since the beginning of the run
     int32_t report_interval_ms;
+
     bool flag_enable_send_msg;
     int32_t fd;                             // driver descriptor
     volatile uint32_t *map_base;            // driver memory map

src/core/receiver/gnss_flowgraph.cc

@@ -246,8 +246,8 @@ void GNSSFlowgraph::connect()
                                 {
                                     // Connect the multichannel signal source to multiple signal conditioners
                                     // GNURADIO max_streams=-1 means infinite ports!
-                                    LOG(INFO) << "sig_source_.at(i)->get_right_block()->output_signature()->max_streams()=" << sig_source_.at(i)->get_right_block()->output_signature()->max_streams();
+                                    DLOG(INFO) << "sig_source_.at(i)->get_right_block()->output_signature()->max_streams()=" << sig_source_.at(i)->get_right_block()->output_signature()->max_streams();
-                                    LOG(INFO) << "sig_conditioner_.at(signal_conditioner_ID)->get_left_block()->input_signature()=" << sig_conditioner_.at(signal_conditioner_ID)->get_left_block()->input_signature()->max_streams();
+                                    DLOG(INFO) << "sig_conditioner_.at(signal_conditioner_ID)->get_left_block()->input_signature()=" << sig_conditioner_.at(signal_conditioner_ID)->get_left_block()->input_signature()->max_streams();
 
                                     if (sig_source_.at(i)->get_right_block()->output_signature()->max_streams() > 1)
                                         {
@@ -443,10 +443,26 @@ void GNSSFlowgraph::connect()
                                                 {
                                                     // create a FIR low pass filter
                                                     std::vector<float> taps;
+
+                                                    //                                                    float beta = 7.0;
+                                                    //                                                    float halfband = 0.5;
+                                                    //                                                    float fractional_bw = 0.4;
+                                                    //                                                    float rate = 1.0 / static_cast<float>(decimation);
+                                                    //
+                                                    //                                                    float trans_width = rate * (halfband - fractional_bw);
+                                                    //                                                    float mid_transition_band = rate * halfband - trans_width / 2.0;
+                                                    //
+                                                    //                                                    taps = gr::filter::firdes::low_pass(1.0,
+                                                    //                                                        1.0,
+                                                    //                                                        mid_transition_band,
+                                                    //                                                        trans_width,
+                                                    //                                                        gr::filter::firdes::win_type::WIN_KAISER,
+                                                    //                                                        beta);
+
                                                     taps = gr::filter::firdes::low_pass(1.0,
                                                         fs,
                                                         acq_fs / 2.1,
-                                                        acq_fs / 10,
+                                                        acq_fs / 2,
                                                         gr::filter::firdes::win_type::WIN_HAMMING);
 
                                                     gr::basic_block_sptr fir_filter_ccf_ = gr::filter::fir_filter_ccf::make(decimation, taps);

src/core/system_parameters/GPS_L1_CA.h

@@ -83,6 +83,7 @@ const int32_t GPS_L1_CA_HISTORY_DEEP = 100;
     {                          \
         1, 0, 0, 0, 1, 0, 1, 1 \
     }
+const std::string GPS_CA_PREAMBLE = {"10001011"};
 const int32_t GPS_CA_PREAMBLE_LENGTH_BITS = 8;
 const int32_t GPS_CA_PREAMBLE_LENGTH_SYMBOLS = 160;
 const double GPS_CA_PREAMBLE_DURATION_S = 0.160;

src/utils/matlab/libs/plotVEMLTracking.m

@@ -63,7 +63,13 @@ for channelNr = channelList
     
     %% Plot all figures =======================================================
     
-    timeAxisInSeconds = (1:4:settings.msToProcess)/1000;
+    if isfield(trackResults(channelNr), 'prn_start_time_s')
+        timeAxis=trackResults(channelNr).prn_start_time_s;
+        time_label='RX Time (s)';
+    else
+        timeAxis = (1:length(trackResults(channelNr).PRN));
+        time_label='Epoch';
+    end
     
     %----- Discrete-Time Scatter Plot ---------------------------------
     plot(handles(1, 1), trackResults(channelNr).data_I,...
@@ -77,29 +83,26 @@ for channelNr = channelList
     ylabel(handles(1, 1), 'Q prompt');
     
     %----- Nav bits ---------------------------------------------------
-    t = (1:length(trackResults(channelNr).data_I));
+    plot  (handles(1, 2), timeAxis, ...
-    plot  (handles(1, 2), t, ...
         trackResults(channelNr).data_I);
     
     grid  (handles(1, 2));
     title (handles(1, 2), 'Bits of the navigation message');
-    xlabel(handles(1, 2), 'Time (s)');
+    xlabel(handles(1, 2), time_label);
     axis  (handles(1, 2), 'tight');
     
     %----- PLL discriminator unfiltered--------------------------------
-    t = (1:length(trackResults(channelNr).pllDiscr));
+    plot  (handles(2, 1), timeAxis, ...
-    plot  (handles(2, 1), t, ...
         trackResults(channelNr).pllDiscr, 'r');
     
     grid  (handles(2, 1));
     axis  (handles(2, 1), 'tight');
-    xlabel(handles(2, 1), 'Time (s)');
+    xlabel(handles(2, 1), time_label);
     ylabel(handles(2, 1), 'Amplitude');
     title (handles(2, 1), 'Raw PLL discriminator');
     
     %----- Correlation ------------------------------------------------
-    t = (1:length(trackResults(channelNr).I_VE));
+    plot(handles(2, 2), timeAxis, ...
-    plot(handles(2, 2), t, ...
         [sqrt(trackResults(channelNr).I_VE.^2 + ...
         trackResults(channelNr).Q_VE.^2)', ...
         sqrt(trackResults(channelNr).I_E.^2 + ...
@@ -114,7 +117,7 @@ for channelNr = channelList
     
     grid  (handles(2, 2));
     title (handles(2, 2), 'Correlation results');
-    xlabel(handles(2, 2), 'Time (s)');
+    xlabel(handles(2, 2), time_label);
     axis  (handles(2, 2), 'tight');
     
     hLegend = legend(handles(2, 2), '$\sqrt{I_{VE}^2 + Q_{VE}^2}$', ...
@@ -127,35 +130,32 @@ for channelNr = channelList
     set(hLegend, 'Interpreter', 'Latex');
     
     %----- PLL discriminator filtered----------------------------------
-    t = (1:length(trackResults(channelNr).pllDiscrFilt));
+    plot  (handles(3, 1), timeAxis, ...
-    plot  (handles(3, 1), t, ...
         trackResults(channelNr).pllDiscrFilt, 'b');
     
     grid  (handles(3, 1));
     axis  (handles(3, 1), 'tight');
-    xlabel(handles(3, 1), 'Time (s)');
+    xlabel(handles(3, 1), time_label);
     ylabel(handles(3, 1), 'Amplitude');
     title (handles(3, 1), 'Filtered PLL discriminator');
     
     %----- DLL discriminator unfiltered--------------------------------
-    t = (1:length(trackResults(channelNr).dllDiscr));
+    plot  (handles(3, 2), timeAxis, ...
-    plot  (handles(3, 2), t, ...
         trackResults(channelNr).dllDiscr, 'r');
     
     grid  (handles(3, 2));
     axis  (handles(3, 2), 'tight');
-    xlabel(handles(3, 2), 'Time (s)');
+    xlabel(handles(3, 2), time_label);
     ylabel(handles(3, 2), 'Amplitude');
     title (handles(3, 2), 'Raw DLL discriminator');
     
     %----- DLL discriminator filtered----------------------------------
-    t = (1:length(trackResults(channelNr).dllDiscrFilt));
+    plot  (handles(3, 3), timeAxis, ...
-    plot  (handles(3, 3), t, ...
         trackResults(channelNr).dllDiscrFilt, 'b');
     
     grid  (handles(3, 3));
     axis  (handles(3, 3), 'tight');
-    xlabel(handles(3, 3), 'Time (s)');
+    xlabel(handles(3, 3), time_label);
     ylabel(handles(3, 3), 'Amplitude');
     title (handles(3, 3), 'Filtered DLL discriminator');