Merge branch 'new_volk_module' of git+ssh://github.com/gnss-sdr/gnss-sdr

into new_volk_module

# Please enter a commit message to explain why this merge is necessary,
# especially if it merges an updated upstream into a topic branch.
#
# Lines starting with '#' will be ignored, and an empty message aborts
# the commit.

src/algorithms/acquisition/adapters/CMakeLists.txt

@@ -50,6 +50,7 @@ include_directories(
      ${GFlags_INCLUDE_DIRS}
      ${GNURADIO_RUNTIME_INCLUDE_DIRS}
      ${GNURADIO_BLOCKS_INCLUDE_DIRS}
+     ${VOLK_GNSSSDR_INCLUDE_DIRS}
 )
 
 file(GLOB ACQ_ADAPTER_HEADERS "*.h")

src/algorithms/acquisition/adapters/gps_l1_ca_pcps_acquisition.cc

@@ -84,36 +84,36 @@ GpsL1CaPcpsAcquisition::GpsL1CaPcpsAcquisition(
 
     code_ = new gr_complex[vector_length_];
 
-    // if (item_type_.compare("gr_complex") == 0 )
-    //         {
+    if (item_type_.compare("cshort") == 0 )
+	 {
+        item_size_ = sizeof(lv_16sc_t);
+        acquisition_sc_ = pcps_make_acquisition_sc(sampled_ms_, max_dwells_,
+                shift_resolution_, if_, fs_in_, code_length_, code_length_,
+                bit_transition_flag_, queue_, dump_, dump_filename_);
+        DLOG(INFO) << "acquisition(" << acquisition_cc_->unique_id() << ")";
+
+	 }else{
 		 item_size_ = sizeof(gr_complex);
 		 acquisition_cc_ = pcps_make_acquisition_cc(sampled_ms_, max_dwells_,
             shift_resolution_, if_, fs_in_, code_length_, code_length_,
             bit_transition_flag_, queue_, dump_, dump_filename_);
+		 DLOG(INFO) << "acquisition(" << acquisition_cc_->unique_id() << ")";
+	 }
 
     stream_to_vector_ = gr::blocks::stream_to_vector::make(item_size_, vector_length_);
-
     DLOG(INFO) << "stream_to_vector(" << stream_to_vector_->unique_id() << ")";
-    DLOG(INFO) << "acquisition(" << acquisition_cc_->unique_id() << ")";
+    //now is supported natively by the acquisition (_sc variant)
+//    if (item_type_.compare("cshort") == 0)
+//        {
+//            cshort_to_float_x2_ = make_cshort_to_float_x2();
+//            float_to_complex_ = gr::blocks::float_to_complex::make();
 //        }
 
-    if (item_type_.compare("cshort") == 0)
-        {
-            cshort_to_float_x2_ = make_cshort_to_float_x2();
-            float_to_complex_ = gr::blocks::float_to_complex::make();
-        }
-
     if (item_type_.compare("cbyte") == 0)
         {
             cbyte_to_float_x2_ = make_complex_byte_to_float_x2();
             float_to_complex_ = gr::blocks::float_to_complex::make();
         }
-    //}
-    //else
-    // {
-    //     LOG(WARNING) << item_type_
-    //             << " unknown acquisition item type";
-    // }
     channel_ = 0;
     threshold_ = 0.0;
     doppler_max_ = 0;
@@ -132,10 +132,13 @@ GpsL1CaPcpsAcquisition::~GpsL1CaPcpsAcquisition()
 void GpsL1CaPcpsAcquisition::set_channel(unsigned int channel)
 {
     channel_ = channel;
-    //if (item_type_.compare("gr_complex") == 0)
-    //{
+    if (item_type_.compare("cshort") == 0)
+    {
+    	acquisition_sc_->set_channel(channel_);
+    }else{
         acquisition_cc_->set_channel(channel_);
-    //}
+    }
+
 }
 
 
@@ -155,30 +158,39 @@ void GpsL1CaPcpsAcquisition::set_threshold(float threshold)
 
     DLOG(INFO) << "Channel " << channel_ << " Threshold = " << threshold_;
 
-   // if (item_type_.compare("gr_complex") == 0)
-    //    {
+
+    if (item_type_.compare("cshort") == 0)
+    {
+    	acquisition_sc_->set_threshold(threshold_);
+    }else{
         acquisition_cc_->set_threshold(threshold_);
-    //    }
+    }
 }
 
 
 void GpsL1CaPcpsAcquisition::set_doppler_max(unsigned int doppler_max)
 {
     doppler_max_ = doppler_max;
-    //   if (item_type_.compare("gr_complex") == 0)
-    //  {
+
+    if (item_type_.compare("cshort") == 0)
+    {
+    	acquisition_sc_->set_doppler_max(doppler_max_);
+    }else{
         acquisition_cc_->set_doppler_max(doppler_max_);
-    // }
+    }
 }
 
 
 void GpsL1CaPcpsAcquisition::set_doppler_step(unsigned int doppler_step)
 {
     doppler_step_ = doppler_step;
-    //   if (item_type_.compare("gr_complex") == 0)
-    //      {
+
+    if (item_type_.compare("cshort") == 0)
+     {
+     	acquisition_sc_->set_doppler_step(doppler_step_);
+     }else{
          acquisition_cc_->set_doppler_step(doppler_step_);
-    //     }
+     }
 
 }
 
@@ -187,39 +199,49 @@ void GpsL1CaPcpsAcquisition::set_channel_queue(
         concurrent_queue<int> *channel_internal_queue)
 {
     channel_internal_queue_ = channel_internal_queue;
-    //  if (item_type_.compare("gr_complex") == 0)
-    //  {
+
+    if (item_type_.compare("cshort") == 0)
+     {
+     	acquisition_sc_->set_channel_queue(channel_internal_queue_);
+     }else{
          acquisition_cc_->set_channel_queue(channel_internal_queue_);
-    //  }
+     }
 }
 
 
 void GpsL1CaPcpsAcquisition::set_gnss_synchro(Gnss_Synchro* gnss_synchro)
 {
     gnss_synchro_ = gnss_synchro;
-    // if (item_type_.compare("gr_complex") == 0)
-    // {
+
+    if (item_type_.compare("cshort") == 0)
+     {
+     	acquisition_sc_->set_gnss_synchro(gnss_synchro_);
+     }else{
          acquisition_cc_->set_gnss_synchro(gnss_synchro_);
-    // }
+     }
 }
 
 
 signed int GpsL1CaPcpsAcquisition::mag()
 {
-    // //    if (item_type_.compare("gr_complex") == 0)
-    //        {
+    if (item_type_.compare("cshort") == 0)
+     {
+    	return acquisition_sc_->mag();
+     }else{
     	return acquisition_cc_->mag();
-    //       }
-    //   else
-    //       {
-    //           return 0;
-    //      }
+     }
 }
 
 
 void GpsL1CaPcpsAcquisition::init()
 {
+    if (item_type_.compare("cshort") == 0)
+     {
+    	acquisition_sc_->init();
+     }else{
     	acquisition_cc_->init();
+     }
+
     set_local_code();
 }
 
@@ -238,7 +260,13 @@ void GpsL1CaPcpsAcquisition::set_local_code()
                     sizeof(gr_complex)*code_length_);
         }
 
+
+    if (item_type_.compare("cshort") == 0)
+     {
+    	acquisition_sc_->set_local_code(code_);
+     }else{
     	acquisition_cc_->set_local_code(code_);
+     }
 
     delete[] code;
     //  }
@@ -247,18 +275,23 @@ void GpsL1CaPcpsAcquisition::set_local_code()
 
 void GpsL1CaPcpsAcquisition::reset()
 {
-    //  if (item_type_.compare("gr_complex") == 0)
-    //  {
+
+    if (item_type_.compare("cshort") == 0)
+     {
+    	acquisition_sc_->set_active(true);
+     }else{
     	acquisition_cc_->set_active(true);
-    //  }
+     }
 }
 
 void GpsL1CaPcpsAcquisition::set_state(int state)
 {
-    //  if (item_type_.compare("gr_complex") == 0)
-    //  {
+    if (item_type_.compare("cshort") == 0)
+     {
+    	acquisition_sc_->set_state(state);
+     }else{
     	acquisition_cc_->set_state(state);
-    //  }
+     }
 }
 
 
@@ -291,10 +324,12 @@ void GpsL1CaPcpsAcquisition::connect(gr::top_block_sptr top_block)
         }
     else if (item_type_.compare("cshort") == 0)
         {
-            top_block->connect(cshort_to_float_x2_, 0, float_to_complex_, 0);
-            top_block->connect(cshort_to_float_x2_, 1, float_to_complex_, 1);
-            top_block->connect(float_to_complex_, 0, stream_to_vector_, 0);
-            top_block->connect(stream_to_vector_, 0, acquisition_cc_, 0);
+            //top_block->connect(cshort_to_float_x2_, 0, float_to_complex_, 0);
+            //top_block->connect(cshort_to_float_x2_, 1, float_to_complex_, 1);
+            //top_block->connect(float_to_complex_, 0, stream_to_vector_, 0);
+            //top_block->connect(stream_to_vector_, 0, acquisition_cc_, 0);
+    		top_block->connect(stream_to_vector_, 0, acquisition_sc_, 0);
+
         }
     else if (item_type_.compare("cbyte") == 0)
         {
@@ -320,10 +355,11 @@ void GpsL1CaPcpsAcquisition::disconnect(gr::top_block_sptr top_block)
         {
             // Since a short-based acq implementation is not available,
             // we just convert cshorts to gr_complex
-            top_block->disconnect(cshort_to_float_x2_, 0, float_to_complex_, 0);
-            top_block->disconnect(cshort_to_float_x2_, 1, float_to_complex_, 1);
-            top_block->disconnect(float_to_complex_, 0, stream_to_vector_, 0);
-            top_block->disconnect(stream_to_vector_, 0, acquisition_cc_, 0);
+            //top_block->disconnect(cshort_to_float_x2_, 0, float_to_complex_, 0);
+            //top_block->disconnect(cshort_to_float_x2_, 1, float_to_complex_, 1);
+            //top_block->disconnect(float_to_complex_, 0, stream_to_vector_, 0);
+            //top_block->disconnect(stream_to_vector_, 0, acquisition_cc_, 0);
+    		top_block->disconnect(stream_to_vector_, 0, acquisition_sc_, 0);
         }
     else if (item_type_.compare("cbyte") == 0)
         {
@@ -349,7 +385,8 @@ gr::basic_block_sptr GpsL1CaPcpsAcquisition::get_left_block()
         }
     else if (item_type_.compare("cshort") == 0)
         {
-            return cshort_to_float_x2_;
+            //return cshort_to_float_x2_;
+    		return stream_to_vector_;
         }
     else if (item_type_.compare("cbyte") == 0)
         {
@@ -365,6 +402,11 @@ gr::basic_block_sptr GpsL1CaPcpsAcquisition::get_left_block()
 
 gr::basic_block_sptr GpsL1CaPcpsAcquisition::get_right_block()
 {
+	if (item_type_.compare("cshort") == 0)
+	{
+		return acquisition_sc_;
+	}else{
 		return acquisition_cc_;
 	}
+}
 

src/algorithms/acquisition/adapters/gps_l1_ca_pcps_acquisition.h

@@ -43,8 +43,10 @@
 #include "gnss_synchro.h"
 #include "acquisition_interface.h"
 #include "pcps_acquisition_cc.h"
+#include "pcps_acquisition_sc.h"
 #include "cshort_to_float_x2.h"
 #include "complex_byte_to_float_x2.h"
+#include <volk_gnsssdr/volk_gnsssdr.h>
 
 
 
@@ -145,6 +147,7 @@ public:
 private:
     ConfigurationInterface* configuration_;
     pcps_acquisition_cc_sptr acquisition_cc_;
+    pcps_acquisition_sc_sptr acquisition_sc_;
     gr::blocks::stream_to_vector::sptr stream_to_vector_;
     gr::blocks::float_to_complex::sptr float_to_complex_;
     cshort_to_float_x2_sptr cshort_to_float_x2_;

src/algorithms/acquisition/gnuradio_blocks/CMakeLists.txt

@@ -19,6 +19,7 @@
 
 set(ACQ_GR_BLOCKS_SOURCES
     pcps_acquisition_cc.cc
+    pcps_acquisition_sc.cc
     pcps_multithread_acquisition_cc.cc
     pcps_assisted_acquisition_cc.cc
     pcps_acquisition_fine_doppler_cc.cc
@@ -42,6 +43,7 @@ include_directories(
      ${GLOG_INCLUDE_DIRS}
      ${GFlags_INCLUDE_DIRS}
      ${GNURADIO_RUNTIME_INCLUDE_DIRS}
+     ${VOLK_GNSSSDR_INCLUDE_DIRS}
 )
 
 
@@ -57,5 +59,5 @@ endif(OPENCL_FOUND)
 file(GLOB ACQ_GR_BLOCKS_HEADERS "*.h")
 add_library(acq_gr_blocks ${ACQ_GR_BLOCKS_SOURCES} ${ACQ_GR_BLOCKS_HEADERS})
 source_group(Headers FILES ${ACQ_GR_BLOCKS_HEADERS}) 
-target_link_libraries(acq_gr_blocks gnss_sp_libs gnss_system_parameters ${GNURADIO_RUNTIME_LIBRARIES} ${GNURADIO_FFT_LIBRARIES} ${VOLK_LIBRARIES} ${OPT_LIBRARIES})
+target_link_libraries(acq_gr_blocks gnss_sp_libs gnss_system_parameters ${GNURADIO_RUNTIME_LIBRARIES} ${GNURADIO_FFT_LIBRARIES} ${VOLK_LIBRARIES} ${VOLK_GNSSSDR_LIBRARIES} ${OPT_LIBRARIES})
 

src/algorithms/acquisition/gnuradio_blocks/pcps_acquisition_sc.cc

@@ -0,0 +1,472 @@
+/*!
+ * \file pcps_acquisition_sc.cc
+ * \brief This class implements a Parallel Code Phase Search Acquisition
+ * \authors <ul>
+ *          <li> Javier Arribas, 2011. jarribas(at)cttc.es
+ *          <li> Luis Esteve, 2012. luis(at)epsilon-formacion.com
+ *          <li> Marc Molina, 2013. marc.molina.pena@gmail.com
+ *          </ul>
+ *
+ * -------------------------------------------------------------------------
+ *
+ * Copyright (C) 2010-2015  (see AUTHORS file for a list of contributors)
+ *
+ * GNSS-SDR is a software defined Global Navigation
+ *          Satellite Systems receiver
+ *
+ * This file is part of GNSS-SDR.
+ *
+ * GNSS-SDR is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * GNSS-SDR is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GNSS-SDR. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * -------------------------------------------------------------------------
+ */
+
+#include "pcps_acquisition_sc.h"
+#include <sstream>
+#include <boost/filesystem.hpp>
+#include <gnuradio/io_signature.h>
+#include <glog/logging.h>
+#include <volk/volk.h>
+#include "gnss_signal_processing.h"
+#include "control_message_factory.h"
+#include <volk_gnsssdr/volk_gnsssdr.h>
+
+using google::LogMessage;
+
+pcps_acquisition_sc_sptr pcps_make_acquisition_sc(
+                                 unsigned int sampled_ms, unsigned int max_dwells,
+                                 unsigned int doppler_max, long freq, long fs_in,
+                                 int samples_per_ms, int samples_per_code,
+                                 bool bit_transition_flag,
+                                 gr::msg_queue::sptr queue, bool dump,
+                                 std::string dump_filename)
+{
+
+    return pcps_acquisition_sc_sptr(
+            new pcps_acquisition_sc(sampled_ms, max_dwells, doppler_max, freq, fs_in, samples_per_ms,
+                                     samples_per_code, bit_transition_flag, queue, dump, dump_filename));
+}
+
+pcps_acquisition_sc::pcps_acquisition_sc(
+                         unsigned int sampled_ms, unsigned int max_dwells,
+                         unsigned int doppler_max, long freq, long fs_in,
+                         int samples_per_ms, int samples_per_code,
+                         bool bit_transition_flag,
+                         gr::msg_queue::sptr queue, bool dump,
+                         std::string dump_filename) :
+    gr::block("pcps_acquisition_sc",
+    gr::io_signature::make(1, 1, sizeof(lv_16sc_t) * sampled_ms * samples_per_ms * ( bit_transition_flag ? 2 : 1 )),
+    gr::io_signature::make(0, 0, 0))
+{
+    d_sample_counter = 0;    // SAMPLE COUNTER
+    d_active = false;
+    d_state = 0;
+    d_queue = queue;
+    d_freq = freq;
+    d_fs_in = fs_in;
+    d_samples_per_ms = samples_per_ms;
+    d_samples_per_code = samples_per_code;
+    d_sampled_ms = sampled_ms;
+    d_max_dwells = max_dwells;
+    d_well_count = 0;
+    d_doppler_max = doppler_max;
+    d_fft_size = d_sampled_ms * d_samples_per_ms;
+    d_mag = 0;
+    d_input_power = 0.0;
+    d_num_doppler_bins = 0;
+    d_bit_transition_flag = bit_transition_flag;
+    d_threshold = 0.0;
+    d_doppler_step = 250;
+    d_code_phase = 0;
+    d_test_statistics = 0.0;
+    d_channel = 0;
+    d_doppler_freq = 0.0;
+
+    //set_relative_rate( 1.0/d_fft_size );
+
+    // COD:
+    // Experimenting with the overlap/save technique for handling bit trannsitions
+    // The problem: Circular correlation is asynchronous with the received code.
+    // In effect the first code phase used in the correlation is the current
+    // estimate of the code phase at the start of the input buffer. If this is 1/2
+    // of the code period a bit transition would move all the signal energy into
+    // adjacent frequency bands at +/- 1/T where T is the integration time.
+    //
+    // We can avoid this by doing linear correlation, effectively doubling the
+    // size of the input buffer and padding the code with zeros.
+    if( d_bit_transition_flag )
+    {
+        d_fft_size *= 2;
+        d_max_dwells = 1;
+    }
+
+    d_fft_codes = static_cast<gr_complex*>(volk_malloc(d_fft_size * sizeof(gr_complex), volk_get_alignment()));
+    d_magnitude = static_cast<float*>(volk_malloc(d_fft_size * sizeof(float), volk_get_alignment()));
+    //temporary storage for the input conversion from 16sc to float 32fc
+    d_in_32fc = static_cast<gr_complex*>(volk_malloc(d_fft_size * sizeof(gr_complex), volk_get_alignment()));
+
+    // Direct FFT
+    d_fft_if = new gr::fft::fft_complex(d_fft_size, true);
+
+    // Inverse FFT
+    d_ifft = new gr::fft::fft_complex(d_fft_size, false);
+
+    // For dumping samples into a file
+    d_dump = dump;
+    d_dump_filename = dump_filename;
+
+    d_gnss_synchro = 0;
+    d_channel_internal_queue = 0;
+    d_grid_doppler_wipeoffs = 0;
+}
+
+pcps_acquisition_sc::~pcps_acquisition_sc()
+{
+    if (d_num_doppler_bins > 0)
+        {
+            for (unsigned int i = 0; i < d_num_doppler_bins; i++)
+                {
+                    volk_free(d_grid_doppler_wipeoffs[i]);
+                }
+            delete[] d_grid_doppler_wipeoffs;
+        }
+
+    volk_free(d_fft_codes);
+    volk_free(d_magnitude);
+    volk_free(d_in_32fc);
+
+    delete d_ifft;
+    delete d_fft_if;
+
+    if (d_dump)
+        {
+            d_dump_file.close();
+        }
+}
+
+void pcps_acquisition_sc::set_local_code(std::complex<float> * code)
+{
+    // COD
+    // Here we want to create a buffer that looks like this:
+    // [ 0 0 0 ... 0 c_0 c_1 ... c_L]
+    // where c_i is the local code and there are L zeros and L chips
+    int offset = 0;
+    if( d_bit_transition_flag )
+    {
+        std::fill_n( d_fft_if->get_inbuf(), d_samples_per_code, gr_complex( 0.0, 0.0 ) );
+        offset = d_samples_per_code;
+    }
+    memcpy(d_fft_if->get_inbuf() + offset, code, sizeof(gr_complex) * d_samples_per_code);
+    d_fft_if->execute(); // We need the FFT of local code
+    volk_32fc_conjugate_32fc(d_fft_codes, d_fft_if->get_outbuf(), d_fft_size);
+}
+
+void pcps_acquisition_sc::init()
+{
+    d_gnss_synchro->Acq_delay_samples = 0.0;
+    d_gnss_synchro->Acq_doppler_hz = 0.0;
+    d_gnss_synchro->Acq_samplestamp_samples = 0;
+    d_mag = 0.0;
+    d_input_power = 0.0;
+
+    d_num_doppler_bins = ceil( static_cast<double>(static_cast<int>(d_doppler_max) - static_cast<int>(-d_doppler_max)) / static_cast<double>(d_doppler_step));
+
+    // Create the carrier Doppler wipeoff signals
+    d_grid_doppler_wipeoffs = new gr_complex*[d_num_doppler_bins];
+
+    for (unsigned int doppler_index = 0; doppler_index < d_num_doppler_bins; doppler_index++)
+        {
+            d_grid_doppler_wipeoffs[doppler_index] = static_cast<gr_complex*>(volk_malloc(d_fft_size * sizeof(gr_complex), volk_get_alignment()));
+            int doppler = -static_cast<int>(d_doppler_max) + d_doppler_step * doppler_index;
+            complex_exp_gen(d_grid_doppler_wipeoffs[doppler_index], -d_freq - doppler, d_fs_in, d_fft_size);
+        }
+}
+
+
+
+void pcps_acquisition_sc::set_state(int state)
+    {
+        d_state = state;
+        if (d_state == 1)
+            {
+                d_gnss_synchro->Acq_delay_samples = 0.0;
+                d_gnss_synchro->Acq_doppler_hz = 0.0;
+                d_gnss_synchro->Acq_samplestamp_samples = 0;
+                d_well_count = 0;
+                d_mag = 0.0;
+                d_input_power = 0.0;
+                d_test_statistics = 0.0;
+            }
+        else if (d_state == 0)
+            {}
+        else
+            {
+                LOG(ERROR) << "State can only be set to 0 or 1";
+            }
+    }
+
+int pcps_acquisition_sc::general_work(int noutput_items,
+        gr_vector_int &ninput_items, gr_vector_const_void_star &input_items,
+        gr_vector_void_star &output_items)
+{
+    /*
+     * By J.Arribas, L.Esteve and M.Molina
+     * Acquisition strategy (Kay Borre book + CFAR threshold):
+     * 1. Compute the input signal power estimation
+     * 2. Doppler serial search loop
+     * 3. Perform the FFT-based circular convolution (parallel time search)
+     * 4. Record the maximum peak and the associated synchronization parameters
+     * 5. Compute the test statistics and compare to the threshold
+     * 6. Declare positive or negative acquisition using a message queue
+     */
+
+    int acquisition_message = -1; //0=STOP_CHANNEL 1=ACQ_SUCCEES 2=ACQ_FAIL
+
+    switch (d_state)
+    {
+    case 0:
+        {
+            if (d_active)
+                {
+                    //restart acquisition variables
+                    d_gnss_synchro->Acq_delay_samples = 0.0;
+                    d_gnss_synchro->Acq_doppler_hz = 0.0;
+                    d_gnss_synchro->Acq_samplestamp_samples = 0;
+                    d_well_count = 0;
+                    d_mag = 0.0;
+                    d_input_power = 0.0;
+                    d_test_statistics = 0.0;
+
+                    d_state = 1;
+                }
+
+            d_sample_counter += d_fft_size * ninput_items[0]; // sample counter
+            consume_each(ninput_items[0]);
+
+            //DLOG(INFO) << "Consumed " << ninput_items[0] << " items";
+
+            break;
+        }
+
+    case 1:
+        {
+            // initialize acquisition algorithm
+            int doppler;
+            unsigned int indext = 0;
+            float magt = 0.0;
+            const lv_16sc_t *in = (const lv_16sc_t *)input_items[0]; //Get the input samples pointer
+            int effective_fft_size = ( d_bit_transition_flag ? d_fft_size/2 : d_fft_size );
+
+            //TODO: optimize the signal processing chain to not use gr_complex. This is a temporary solution
+            volk_gnsssdr_16ic_convert_32fc(d_in_32fc,in,effective_fft_size);
+
+            float fft_normalization_factor = static_cast<float>(d_fft_size) * static_cast<float>(d_fft_size);
+
+            d_input_power = 0.0;
+            d_mag = 0.0;
+
+            d_sample_counter += d_fft_size; // sample counter
+
+            d_well_count++;
+
+            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;
+
+            // 1- Compute the input signal power estimation
+            volk_32fc_magnitude_squared_32f(d_magnitude, d_in_32fc, d_fft_size);
+            volk_32f_accumulator_s32f(&d_input_power, d_magnitude, d_fft_size);
+            d_input_power /= static_cast<float>(d_fft_size);
+            // 2- Doppler frequency search loop
+            for (unsigned int doppler_index=0; doppler_index < d_num_doppler_bins; doppler_index++)
+                {
+                    // doppler search steps
+
+                    doppler = -static_cast<int>(d_doppler_max) + d_doppler_step * doppler_index;
+
+                    volk_32fc_x2_multiply_32fc(d_fft_if->get_inbuf(), d_in_32fc,
+                                d_grid_doppler_wipeoffs[doppler_index], d_fft_size);
+
+                    // 3- Perform the FFT-based convolution  (parallel time search)
+                    // Compute the FFT of the carrier wiped--off incoming signal
+                    d_fft_if->execute();
+
+                    // Multiply carrier wiped--off, Fourier transformed incoming signal
+                    // with the local FFT'd code reference using SIMD operations with VOLK library
+                    volk_32fc_x2_multiply_32fc(d_ifft->get_inbuf(),
+                                d_fft_if->get_outbuf(), d_fft_codes, d_fft_size);
+
+                    // compute the inverse FFT
+                    d_ifft->execute();
+
+                    // Search maximum
+                    size_t offset = ( d_bit_transition_flag ? effective_fft_size : 0 );
+                    volk_32fc_magnitude_squared_32f(d_magnitude, d_ifft->get_outbuf() + offset, effective_fft_size);
+                    volk_32f_index_max_16u(&indext, d_magnitude, effective_fft_size);
+
+                    // Normalize the maximum value to correct the scale factor introduced by FFTW
+                    magt = d_magnitude[indext] / (fft_normalization_factor * fft_normalization_factor);
+
+                    // 4- record the maximum peak and the associated synchronization parameters
+                    if (d_mag < magt)
+                        {
+                            d_mag = magt;
+
+                            // In case that d_bit_transition_flag = true, we compare the potentially
+                            // new maximum test statistics (d_mag/d_input_power) with the value in
+                            // d_test_statistics. When the second dwell is being processed, the value
+                            // of d_mag/d_input_power could be lower than d_test_statistics (i.e,
+                            // the maximum test statistics in the previous dwell is greater than
+                            // current d_mag/d_input_power). Note that d_test_statistics is not
+                            // restarted between consecutive dwells in multidwell operation.
+                            if (d_test_statistics < (d_mag / d_input_power) || !d_bit_transition_flag)
+                            {
+                                d_gnss_synchro->Acq_delay_samples = static_cast<double>(indext % d_samples_per_code);
+                                d_gnss_synchro->Acq_doppler_hz = static_cast<double>(doppler);
+                                d_gnss_synchro->Acq_samplestamp_samples = d_sample_counter;
+
+                                // 5- Compute the test statistics and compare to the threshold
+                                //d_test_statistics = 2 * d_fft_size * d_mag / d_input_power;
+                                d_test_statistics = d_mag / d_input_power;
+                            }
+                        }
+
+                    // Record results to file if required
+                    if (d_dump)
+                        {
+                            std::stringstream filename;
+                            std::streamsize n = 2 * sizeof(float) * (d_fft_size); // complex file write
+                            filename.str("");
+
+                            boost::filesystem::path p = d_dump_filename;
+                            filename << p.parent_path().string()
+                                     << boost::filesystem::path::preferred_separator
+                                     << p.stem().string()
+                                     << "_" << d_gnss_synchro->System
+                                     <<"_" << d_gnss_synchro->Signal << "_sat_"
+                                     << d_gnss_synchro->PRN << "_doppler_"
+                                     <<  doppler
+                                     << p.extension().string();
+
+                            DLOG(INFO) << "Writing ACQ out to " << filename.str();
+
+                            d_dump_file.open(filename.str().c_str(), std::ios::out | std::ios::binary);
+                            d_dump_file.write((char*)d_ifft->get_outbuf(), n); //write directly |abs(x)|^2 in this Doppler bin?
+                            d_dump_file.close();
+                        }
+                }
+
+            if (!d_bit_transition_flag)
+                {
+                    if (d_test_statistics > d_threshold)
+                        {
+                            d_state = 2; // Positive acquisition
+                        }
+                    else if (d_well_count == d_max_dwells)
+                        {
+                            d_state = 3; // Negative acquisition
+                        }
+                }
+            else
+                {
+                    if (d_well_count == d_max_dwells) // d_max_dwells = 2
+                        {
+                            if (d_test_statistics > d_threshold)
+                                {
+                                    d_state = 2; // Positive acquisition
+                                }
+                            else
+                                {
+                                    d_state = 3; // Negative acquisition
+                                }
+                        }
+                }
+
+            consume_each(1);
+
+            DLOG(INFO) << "Done. Consumed 1 item.";
+
+            break;
+        }
+
+    case 2:
+        {
+            // 6.1- Declare positive acquisition using a message queue
+            DLOG(INFO) << "positive acquisition";
+            DLOG(INFO) << "satellite " << d_gnss_synchro->System << " " << d_gnss_synchro->PRN;
+            DLOG(INFO) << "sample_stamp " << d_sample_counter;
+            DLOG(INFO) << "test statistics value " << d_test_statistics;
+            DLOG(INFO) << "test statistics threshold " << d_threshold;
+            DLOG(INFO) << "code phase " << d_gnss_synchro->Acq_delay_samples;
+            DLOG(INFO) << "doppler " << d_gnss_synchro->Acq_doppler_hz;
+            DLOG(INFO) << "magnitude " << d_mag;
+            DLOG(INFO) << "input signal power " << d_input_power;
+
+            d_active = false;
+            d_state = 0;
+
+            d_sample_counter += d_fft_size * ninput_items[0]; // sample counter
+            consume_each(ninput_items[0]);
+
+            acquisition_message = 1;
+            d_channel_internal_queue->push(acquisition_message);
+
+            break;
+        }
+
+    case 3:
+        {
+            // 6.2- Declare negative acquisition using a message queue
+            DLOG(INFO) << "negative acquisition";
+            DLOG(INFO) << "satellite " << d_gnss_synchro->System << " " << d_gnss_synchro->PRN;
+            DLOG(INFO) << "sample_stamp " << d_sample_counter;
+            DLOG(INFO) << "test statistics value " << d_test_statistics;
+            DLOG(INFO) << "test statistics threshold " << d_threshold;
+            DLOG(INFO) << "code phase " << d_gnss_synchro->Acq_delay_samples;
+            DLOG(INFO) << "doppler " << d_gnss_synchro->Acq_doppler_hz;
+            DLOG(INFO) << "magnitude " << d_mag;
+            DLOG(INFO) << "input signal power " << d_input_power;
+
+            d_active = false;
+            d_state = 0;
+
+            d_sample_counter += d_fft_size * ninput_items[0]; // sample counter
+            consume_each(ninput_items[0]);
+            acquisition_message = 2;
+            d_channel_internal_queue->push(acquisition_message);
+
+            break;
+        }
+    }
+
+    output_items.clear();  // removes a warning
+    return noutput_items;
+}
+
+
+//void pcps_acquisition_sc::forecast (int noutput_items, gr_vector_int &ninput_items_required)
+//{
+    //// COD:
+    //// For zero-padded case we need one extra code period
+    //if( d_bit_transition_flag )
+    //{
+        //ninput_items_required[0] = noutput_items*(d_samples_per_code * d_max_dwells + d_samples_per_code);
+    //}
+    //else
+    //{
+        //ninput_items_required[0] = noutput_items*d_fft_size*d_max_dwells;
+    //}
+//}

src/algorithms/acquisition/gnuradio_blocks/pcps_acquisition_sc.h

@@ -0,0 +1,244 @@
+/*!
+ * \file pcps_acquisition_sc.h
+ * \brief This class implements a Parallel Code Phase Search Acquisition
+ *
+ *  Acquisition strategy (Kay Borre book + CFAR threshold).
+ *  <ol>
+ *  <li> Compute the input signal power estimation
+ *  <li> Doppler serial search loop
+ *  <li> Perform the FFT-based circular convolution (parallel time search)
+ *  <li> Record the maximum peak and the associated synchronization parameters
+ *  <li> Compute the test statistics and compare to the threshold
+ *  <li> Declare positive or negative acquisition using a message queue
+ *  </ol>
+ *
+ * Kay Borre book: K.Borre, D.M.Akos, N.Bertelsen, P.Rinder, and S.H.Jensen,
+ * "A Software-Defined GPS and Galileo Receiver. A Single-Frequency
+ * Approach", Birkha user, 2007. pp 81-84
+ *
+ * \authors <ul>
+ *          <li> Javier Arribas, 2011. jarribas(at)cttc.es
+ *          <li> Luis Esteve, 2012. luis(at)epsilon-formacion.com
+ *          <li> Marc Molina, 2013. marc.molina.pena@gmail.com
+ *          </ul>
+ *
+ * -------------------------------------------------------------------------
+ *
+ * Copyright (C) 2010-2015  (see AUTHORS file for a list of contributors)
+ *
+ * GNSS-SDR is a software defined Global Navigation
+ *          Satellite Systems receiver
+ *
+ * This file is part of GNSS-SDR.
+ *
+ * GNSS-SDR is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * GNSS-SDR is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GNSS-SDR. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * -------------------------------------------------------------------------
+ */
+
+#ifndef GNSS_SDR_PCPS_ACQUISITION_SC_H_
+#define GNSS_SDR_PCPS_ACQUISITION_SC_H_
+
+#include <fstream>
+#include <string>
+#include <gnuradio/block.h>
+#include <gnuradio/msg_queue.h>
+#include <gnuradio/gr_complex.h>
+#include <gnuradio/fft/fft.h>
+#include "concurrent_queue.h"
+#include "gnss_synchro.h"
+
+class pcps_acquisition_sc;
+
+typedef boost::shared_ptr<pcps_acquisition_sc> pcps_acquisition_sc_sptr;
+
+pcps_acquisition_sc_sptr
+pcps_make_acquisition_sc(unsigned int sampled_ms, unsigned int max_dwells,
+                         unsigned int doppler_max, long freq, long fs_in,
+                         int samples_per_ms, int samples_per_code,
+                         bool bit_transition_flag,
+                         gr::msg_queue::sptr queue, bool dump,
+                         std::string dump_filename);
+
+/*!
+ * \brief This class implements a Parallel Code Phase Search Acquisition.
+ *
+ * Check \ref Navitec2012 "An Open Source Galileo E1 Software Receiver",
+ * Algorithm 1, for a pseudocode description of this implementation.
+ */
+class pcps_acquisition_sc: public gr::block
+{
+private:
+    friend pcps_acquisition_sc_sptr
+    pcps_make_acquisition_sc(unsigned int sampled_ms, unsigned int max_dwells,
+            unsigned int doppler_max, long freq, long fs_in,
+            int samples_per_ms, int samples_per_code,
+            bool bit_transition_flag,
+            gr::msg_queue::sptr queue, bool dump,
+            std::string dump_filename);
+
+    pcps_acquisition_sc(unsigned int sampled_ms, unsigned int max_dwells,
+            unsigned int doppler_max, long freq, long fs_in,
+            int samples_per_ms, int samples_per_code,
+            bool bit_transition_flag,
+            gr::msg_queue::sptr queue, bool dump,
+            std::string dump_filename);
+
+    void calculate_magnitudes(gr_complex* fft_begin, int doppler_shift,
+            int doppler_offset);
+
+    long d_fs_in;
+    long d_freq;
+    int d_samples_per_ms;
+    int d_samples_per_code;
+    //unsigned int d_doppler_resolution;
+    float d_threshold;
+    std::string d_satellite_str;
+    unsigned int d_doppler_max;
+    unsigned int d_doppler_step;
+    unsigned int d_sampled_ms;
+    unsigned int d_max_dwells;
+    unsigned int d_well_count;
+    unsigned int d_fft_size;
+    unsigned long int d_sample_counter;
+    gr_complex** d_grid_doppler_wipeoffs;
+    unsigned int d_num_doppler_bins;
+    gr_complex* d_fft_codes;
+    gr_complex* d_in_32fc;
+    gr::fft::fft_complex* d_fft_if;
+    gr::fft::fft_complex* d_ifft;
+    Gnss_Synchro *d_gnss_synchro;
+    unsigned int d_code_phase;
+    float d_doppler_freq;
+    float d_mag;
+    float* d_magnitude;
+    float d_input_power;
+    float d_test_statistics;
+    bool d_bit_transition_flag;
+    gr::msg_queue::sptr d_queue;
+    concurrent_queue<int> *d_channel_internal_queue;
+    std::ofstream d_dump_file;
+    bool d_active;
+    int d_state;
+    bool d_dump;
+    unsigned int d_channel;
+    std::string d_dump_filename;
+
+public:
+    /*!
+     * \brief Default destructor.
+     */
+     ~pcps_acquisition_sc();
+
+     /*!
+      * \brief Set acquisition/tracking common Gnss_Synchro object pointer
+      * to exchange synchronization data between acquisition and tracking blocks.
+      * \param p_gnss_synchro Satellite information shared by the processing blocks.
+      */
+     void set_gnss_synchro(Gnss_Synchro* p_gnss_synchro)
+     {
+         d_gnss_synchro = p_gnss_synchro;
+     }
+
+     /*!
+      * \brief Returns the maximum peak of grid search.
+      */
+     unsigned int mag()
+     {
+         return d_mag;
+     }
+
+     /*!
+      * \brief Initializes acquisition algorithm.
+      */
+     void init();
+
+     /*!
+      * \brief Sets local code for PCPS acquisition algorithm.
+      * \param code - Pointer to the PRN code.
+      */
+     void set_local_code(std::complex<float> * code);
+
+     /*!
+      * \brief Starts acquisition algorithm, turning from standby mode to
+      * active mode
+      * \param active - bool that activates/deactivates the block.
+      */
+     void set_active(bool active)
+     {
+         d_active = active;
+     }
+
+     /*!
+      * \brief If set to 1, ensures that acquisition starts at the
+      * first available sample.
+      * \param state - int=1 forces start of acquisition
+      */
+     void set_state(int state);
+
+     /*!
+      * \brief Set acquisition channel unique ID
+      * \param channel - receiver channel.
+      */
+     void set_channel(unsigned int channel)
+     {
+         d_channel = channel;
+     }
+
+     /*!
+      * \brief Set statistics threshold of PCPS algorithm.
+      * \param threshold - Threshold for signal detection (check \ref Navitec2012,
+      * Algorithm 1, for a definition of this threshold).
+      */
+     void set_threshold(float threshold)
+     {
+         d_threshold = threshold;
+     }
+
+     /*!
+      * \brief Set maximum Doppler grid search
+      * \param doppler_max - Maximum Doppler shift considered in the grid search [Hz].
+      */
+     void set_doppler_max(unsigned int doppler_max)
+     {
+         d_doppler_max = doppler_max;
+     }
+
+     /*!
+      * \brief Set Doppler steps for the grid search
+      * \param doppler_step - Frequency bin of the search grid [Hz].
+      */
+     void set_doppler_step(unsigned int doppler_step)
+     {
+         d_doppler_step = doppler_step;
+     }
+
+     /*!
+      * \brief Set tracking channel internal queue.
+      * \param channel_internal_queue - Channel's internal blocks information queue.
+      */
+     void set_channel_queue(concurrent_queue<int> *channel_internal_queue)
+     {
+         d_channel_internal_queue = channel_internal_queue;
+     }
+
+     /*!
+      * \brief Parallel Code Phase Search Acquisition signal processing.
+      */
+     int general_work(int noutput_items, gr_vector_int &ninput_items,
+             gr_vector_const_void_star &input_items,
+             gr_vector_void_star &output_items);
+};
+
+#endif /* GNSS_SDR_PCPS_ACQUISITION_SC_H_*/