Small bug fix and new configuration file ready to receive GPS signals in real-time with USRP devices and appropiate front-ends. Remember to tune the front-end gain (source section in config file) and, in some particular antenna and LNA setups, tune also the acquisition threshold (acquisition section). The configuration is tested on USRP v1 + DBSRX, USRP 2 + DBSRX and USRP B100 + WBX.

git-svn-id: https://svn.code.sf.net/p/gnss-sdr/code/trunk@491 64b25241-fba3-4117-9849-534c7e92360d

conf/gnss-sdr_GPS_USRP_realtime.conf

@@ -0,0 +1,381 @@
+; Default configuration file
+; You can define your own receiver and invoke it by doing
+; gnss-sdr --config_file=my_GNSS_SDR_configuration.conf
+;
+
+[GNSS-SDR]
+
+;######### GLOBAL OPTIONS ##################
+;internal_fs_hz: Internal signal sampling frequency after the signal conditioning stage [Hz].
+GNSS-SDR.internal_fs_hz=2000000
+
+;######### CONTROL_THREAD CONFIG ############
+ControlThread.wait_for_flowgraph=false
+
+;######### SUPL RRLP GPS assistance configuration #####
+GNSS-SDR.SUPL_gps_enabled=false
+GNSS-SDR.SUPL_read_gps_assistance_xml=true
+GNSS-SDR.SUPL_gps_ephemeris_server=supl.nokia.com
+GNSS-SDR.SUPL_gps_ephemeris_port=7275
+GNSS-SDR.SUPL_gps_acquisition_server=supl.google.com
+GNSS-SDR.SUPL_gps_acquisition_port=7275
+GNSS-SDR.SUPL_MCC=244
+GNSS-SDR.SUPL_MNS=5
+GNSS-SDR.SUPL_LAC=0x59e2
+GNSS-SDR.SUPL_CI=0x31b0
+
+;######### SIGNAL_SOURCE CONFIG ############
+;#implementation: Use [File_Signal_Source] or [UHD_Signal_Source] or [GN3S_Signal_Source] (experimental)
+SignalSource.implementation=UHD_Signal_Source
+
+;#filename: path to file with the captured GNSS signal samples to be processed
+SignalSource.filename=/media/DATALOGGER/Agilent GPS Generator/cap2/agilent_cap2.dat
+
+;#item_type: Type and resolution for each of the signal samples. Use only gr_complex in this version.
+SignalSource.item_type=gr_complex
+
+;#sampling_frequency: Original Signal sampling frequency in [Hz] 
+SignalSource.sampling_frequency=2000000
+
+;#freq: RF front-end center frequency in [Hz] 
+SignalSource.freq=1575420000
+
+;#gain: Front-end Gain in [dB] 
+SignalSource.gain=60
+
+;#subdevice: UHD subdevice specification (for USRP1 use A:0 or B:0)
+SignalSource.subdevice=A:0
+
+;#samples: Number of samples to be processed. Notice that 0 indicates the entire file.
+SignalSource.samples=0
+
+;#repeat: Repeat the processing file. Disable this option in this version
+SignalSource.repeat=false
+
+;#dump: Dump the Signal source data to a file. Disable this option in this version
+SignalSource.dump=false
+
+SignalSource.dump_filename=../data/signal_source.dat
+
+
+;#enable_throttle_control: Enabling this option tells the signal source to keep the delay between samples in post processing.
+; it helps to not overload the CPU, but the processing time will be longer. 
+SignalSource.enable_throttle_control=false
+
+
+;######### SIGNAL_CONDITIONER CONFIG ############
+;## It holds blocks to change data type, filter and resample input data. 
+
+;#implementation: Use [Pass_Through] or [Signal_Conditioner]
+;#[Pass_Through] disables this block and the [DataTypeAdapter], [InputFilter] and [Resampler] blocks
+;#[Signal_Conditioner] enables this block. Then you have to configure [DataTypeAdapter], [InputFilter] and [Resampler] blocks
+;SignalConditioner.implementation=Signal_Conditioner
+SignalConditioner.implementation=Pass_Through
+
+;######### DATA_TYPE_ADAPTER CONFIG ############
+;## Changes the type of input data. Please disable it in this version.
+;#implementation: [Pass_Through] disables this block
+DataTypeAdapter.implementation=Pass_Through
+
+;######### INPUT_FILTER CONFIG ############
+;## Filter the input data. Can be combined with frequency translation for IF signals
+
+;#implementation: Use [Pass_Through] or [Fir_Filter] or [Freq_Xlating_Fir_Filter]
+;#[Pass_Through] disables this block
+;#[Fir_Filter] enables a FIR Filter
+;#[Freq_Xlating_Fir_Filter] enables FIR filter and a composite frequency translation that shifts IF down to zero Hz.
+
+;InputFilter.implementation=Fir_Filter
+;InputFilter.implementation=Freq_Xlating_Fir_Filter
+InputFilter.implementation=Pass_Through
+
+;#dump: Dump the filtered data to a file.
+InputFilter.dump=false
+
+;#dump_filename: Log path and filename.
+InputFilter.dump_filename=../data/input_filter.dat
+
+;#The following options are used in the filter design of Fir_Filter and Freq_Xlating_Fir_Filter implementation. 
+;#These options are based on parameters of gnuradio's function: gr_remez.
+;#These function calculates the optimal (in the Chebyshev/minimax sense) FIR filter inpulse reponse given a set of band edges, the desired reponse on those bands, and the weight given to the error in those bands.
+
+;#input_item_type: Type and resolution for input signal samples. Use only gr_complex in this version.
+InputFilter.input_item_type=gr_complex
+
+;#outut_item_type: Type and resolution for output filtered signal samples. Use only gr_complex in this version.
+InputFilter.output_item_type=gr_complex
+
+;#taps_item_type: Type and resolution for the taps of the filter. Use only float in this version.
+InputFilter.taps_item_type=float
+
+;#number_of_taps: Number of taps in the filter. Increasing this parameter increases the processing time
+InputFilter.number_of_taps=5
+
+;#number_of _bands: Number of frequency bands in the filter.
+InputFilter.number_of_bands=2
+
+;#bands: frequency at the band edges [ b1 e1 b2 e2 b3 e3 ...].
+;#Frequency is in the range [0, 1], with 1 being the Nyquist frequency (Fs/2)
+;#The number of band_begin and band_end elements must match the number of bands
+
+InputFilter.band1_begin=0.0
+InputFilter.band1_end=0.45
+InputFilter.band2_begin=0.55
+InputFilter.band2_end=1.0
+
+;#ampl: desired amplitude at the band edges [ a(b1) a(e1) a(b2) a(e2) ...].
+;#The number of ampl_begin and ampl_end elements must match the number of bands
+
+InputFilter.ampl1_begin=1.0
+InputFilter.ampl1_end=1.0
+InputFilter.ampl2_begin=0.0
+InputFilter.ampl2_end=0.0
+
+;#band_error: weighting applied to each band (usually 1).
+;#The number of band_error elements must match the number of bands
+InputFilter.band1_error=1.0
+InputFilter.band2_error=1.0
+
+;#filter_type: one of "bandpass", "hilbert" or "differentiator" 
+InputFilter.filter_type=bandpass
+
+;#grid_density: determines how accurately the filter will be constructed.
+;The minimum value is 16; higher values are slower to compute the filter.
+InputFilter.grid_density=16
+
+;#The following options are used only in Freq_Xlating_Fir_Filter implementation.
+;#InputFilter.IF is the intermediate frequency (in Hz) shifted down to zero Hz
+
+InputFilter.sampling_frequency=2000000
+InputFilter.IF=0
+
+
+
+;######### RESAMPLER CONFIG ############
+;## Resamples the input data. 
+
+;#implementation: Use [Pass_Through] or [Direct_Resampler]
+;#[Pass_Through] disables this block
+;#[Direct_Resampler] enables a resampler that implements a nearest neigbourhood interpolation
+;Resampler.implementation=Direct_Resampler
+Resampler.implementation=Pass_Through
+
+;#dump: Dump the resamplered data to a file.
+Resampler.dump=false
+;#dump_filename: Log path and filename.
+Resampler.dump_filename=../data/resampler.dat
+
+;#item_type: Type and resolution for each of the signal samples. Use only gr_complex in this version.
+Resampler.item_type=gr_complex
+
+;#sample_freq_in: the sample frequency of the input signal
+Resampler.sample_freq_in=8000000
+
+;#sample_freq_out: the desired sample frequency of the output signal
+Resampler.sample_freq_out=2000000
+
+
+;######### CHANNELS GLOBAL CONFIG ############
+;#count: Number of available satellite channels.
+Channels.count=6
+;#in_acquisition: Number of channels simultaneously acquiring
+Channels.in_acquisition=1
+;#system: GPS, GLONASS, Galileo, SBAS or Compass
+;#if the option is disabled by default is assigned GPS
+Channel.system=GPS
+
+;#signal: 
+;# "1C" GPS L1 C/A
+;# "1P" GPS L1 P
+;# "1W" GPS L1 Z-tracking and similar (AS on)
+;# "1Y" GPS L1 Y
+;# "1M" GPS L1 M
+;# "1N" GPS L1 codeless
+;# "2C" GPS L2 C/A
+;# "2D" GPS L2 L1(C/A)+(P2-P1) semi-codeless
+;# "2S" GPS L2 L2C (M)
+;# "2L" GPS L2 L2C (L)
+;# "2X" GPS L2 L2C (M+L)
+;# "2P" GPS L2 P
+;# "2W" GPS L2 Z-tracking and similar (AS on)
+;# "2Y" GPS L2 Y
+;# "2M" GPS GPS L2 M
+;# "2N" GPS L2 codeless
+;# "5I" GPS L5 I
+;# "5Q" GPS L5 Q
+;# "5X" GPS L5 I+Q
+;# "1C" GLONASS G1 C/A
+;# "1P" GLONASS G1 P
+;# "2C" GLONASS G2 C/A  (Glonass M)
+;# "2P" GLONASS G2 P
+;# "1A" GALILEO E1 A (PRS)
+;# "1B" GALILEO E1 B (I/NAV OS/CS/SoL)
+;# "1C" GALILEO E1 C (no data)
+;# "1X" GALILEO E1 B+C
+;# "1Z" GALILEO E1 A+B+C
+;# "5I" GALILEO E5a I (F/NAV OS)
+;# "5Q" GALILEO E5a Q  (no data)
+;# "5X" GALILEO E5a I+Q
+;# "7I" GALILEO E5b I
+;# "7Q" GALILEO E5b Q
+;# "7X" GALILEO E5b I+Q
+;# "8I" GALILEO E5 I
+;# "8Q" GALILEO E5 Q
+;# "8X" GALILEO E5 I+Q
+;# "6A" GALILEO E6 A
+;# "6B" GALILEO E6 B
+;# "6C" GALILEO E6 C
+;# "6X" GALILEO E6 B+C
+;# "6Z" GALILEO E6 A+B+C
+;# "1C" SBAS L1 C/A
+;# "5I" SBAS L5 I
+;# "5Q" SBAS L5 Q
+;# "5X" SBAS L5 I+Q
+;# "2I" COMPASS E2 I
+;# "2Q" COMPASS E2 Q
+;# "2X" COMPASS E2 IQ
+;# "7I" COMPASS E5b I
+;# "7Q" COMPASS E5b Q
+;# "7X" COMPASS E5b IQ
+;# "6I" COMPASS E6 I
+;# "6Q" COMPASS E6 Q
+;# "6X" COMPASS E6 IQ
+;#if the option is disabled by default is assigned "1C" GPS L1 C/A
+Channel.signal=1C
+
+;######### SPECIFIC CHANNELS CONFIG ######
+;#The following options are specific to each channel and overwrite the generic options 
+
+;######### CHANNEL 0 CONFIG ############
+
+Channel0.system=GPS
+Channel0.signal=1C
+
+;#satellite: Satellite PRN ID for this channel. Disable this option to random search
+Channel0.satellite=11
+
+;######### CHANNEL 1 CONFIG ############
+
+Channel1.system=GPS
+Channel1.signal=1C
+Channel1.satellite=18
+
+
+;######### ACQUISITION GLOBAL CONFIG ############
+
+;#dump: Enable or disable the acquisition internal data file logging [true] or [false] 
+Acquisition.dump=false
+;#filename: Log path and filename
+Acquisition.dump_filename=./acq_dump.dat
+;#item_type: Type and resolution for each of the signal samples. Use only gr_complex in this version.
+Acquisition.item_type=gr_complex
+;#if: Signal intermediate frequency in [Hz] 
+Acquisition.if=0
+;#sampled_ms: Signal block duration for the acquisition signal detection [ms]
+Acquisition.coherent_integration_time_ms=1
+;#implementation: Acquisition algorithm selection for this channel: [GPS_L1_CA_PCPS_Acquisition] or [Galileo_E1_PCPS_Ambiguous_Acquisition]
+Acquisition.implementation=GPS_L1_CA_PCPS_Acquisition
+;#threshold: Acquisition threshold. It will be ignored if pfa is defined.
+Acquisition.threshold=0.01
+;#pfa: Acquisition false alarm probability. This option overrides the threshold option. Only use with implementations: [GPS_L1_CA_PCPS_Acquisition] or [Galileo_E1_PCPS_Ambiguous_Acquisition]
+;Acquisition.pfa=0.0001
+;#doppler_max: Maximum expected Doppler shift [Hz]
+Acquisition.doppler_max=10000
+;#doppler_max: Doppler step in the grid search [Hz]
+Acquisition.doppler_step=500
+;#bit_transition_flag: Enable or disable a strategy to deal with bit transitions in GPS signals: process two dwells and take
+maximum test statistics. Only use with implementation: [GPS_L1_CA_PCPS_Acquisition] (should not be used for Galileo_E1_PCPS_Ambiguous_Acquisition])
+Acquisition.bit_transition_flag=false
+;#max_dwells: Maximum number of consecutive dwells to be processed. It will be ignored if bit_transition_flag=true
+Acquisition.max_dwells=1
+
+;######### ACQUISITION CHANNELS CONFIG ######
+;#The following options are specific to each channel and overwrite the generic options
+
+
+;######### TRACKING GLOBAL CONFIG ############
+
+;#implementation: Selected tracking algorithm: [GPS_L1_CA_DLL_PLL_Tracking] or [GPS_L1_CA_DLL_FLL_PLL_Tracking]
+Tracking.implementation=GPS_L1_CA_DLL_PLL_Optim_Tracking
+;#item_type: Type and resolution for each of the signal samples. Use only [gr_complex] in this version.
+Tracking.item_type=gr_complex
+
+;#sampling_frequency: Signal Intermediate Frequency in [Hz] 
+Tracking.if=0
+
+;#dump: Enable or disable the Tracking internal binary data file logging [true] or [false] 
+Tracking.dump=false
+
+;#dump_filename: Log path and filename. Notice that the tracking channel will add "x.dat" where x is the channel number.
+Tracking.dump_filename=./tracking_ch_
+
+;#pll_bw_hz: PLL loop filter bandwidth [Hz]
+Tracking.pll_bw_hz=50.0;
+
+;#dll_bw_hz: DLL loop filter bandwidth [Hz]
+Tracking.dll_bw_hz=2.0;
+
+;#fll_bw_hz: FLL loop filter bandwidth [Hz]
+Tracking.fll_bw_hz=10.0;
+
+;#order: PLL/DLL loop filter order [2] or [3]
+Tracking.order=3;
+
+;#early_late_space_chips: correlator early-late space [chips]. Use [0.5]
+Tracking.early_late_space_chips=0.5;
+
+;######### TELEMETRY DECODER CONFIG ############
+;#implementation: Use [GPS_L1_CA_Telemetry_Decoder] for GPS L1 C/A.
+TelemetryDecoder.implementation=GPS_L1_CA_Telemetry_Decoder
+TelemetryDecoder.dump=false
+
+;######### OBSERVABLES CONFIG ############
+;#implementation: Use [GPS_L1_CA_Observables] for GPS L1 C/A.
+Observables.implementation=GPS_L1_CA_Observables
+
+;#dump: Enable or disable the Observables internal binary data file logging [true] or [false] 
+Observables.dump=false
+
+;#dump_filename: Log path and filename.
+Observables.dump_filename=./observables.dat
+
+
+;######### PVT CONFIG ############
+;#implementation: Position Velocity and Time (PVT) implementation algorithm: Use [GPS_L1_CA_PVT] in this version.
+PVT.implementation=GPS_L1_CA_PVT
+
+;#averaging_depth: Number of PVT observations in the moving average algorithm
+PVT.averaging_depth=10
+
+;#flag_average: Enables the PVT averaging between output intervals (arithmetic mean) [true] or [false] 
+PVT.flag_averaging=true
+
+;#output_rate_ms: Period between two PVT outputs. Notice that the minimum period is equal to the tracking integration time (for GPS CA L1 is 1ms) [ms]
+PVT.output_rate_ms=100
+
+;#display_rate_ms: Position console print (std::out) interval [ms]. Notice that output_rate_ms<=display_rate_ms.
+PVT.display_rate_ms=500
+
+;# RINEX, KML, and NMEA output configuration
+
+;#dump_filename: Log path and filename without extension. Notice that PVT will add ".dat" to the binary dump and ".kml" to GoogleEarth dump.
+PVT.dump_filename=./PVT
+
+;#nmea_dump_filename: NMEA log path and filename
+PVT.nmea_dump_filename=./gnss_sdr_pvt.nmea;
+
+;#flag_nmea_tty_port: Enable or disable the NMEA log to a serial TTY port (Can be used with real hardware or virtual one)
+PVT.flag_nmea_tty_port=false;
+
+;#nmea_dump_devname: serial device descriptor for NMEA logging
+PVT.nmea_dump_devname=/dev/pts/4
+
+
+;#dump: Enable or disable the PVT internal binary data file logging [true] or [false] 
+PVT.dump=false
+
+;######### OUTPUT_FILTER CONFIG ############
+;# Receiver output filter: Leave this block disabled in this version
+OutputFilter.implementation=Null_Sink_Output_Filter
+OutputFilter.filename=data/gnss-sdr.dat
+OutputFilter.item_type=gr_complex

src/algorithms/signal_source/adapters/gn3s_signal_source.cc

@@ -31,6 +31,7 @@
 #include "gn3s_signal_source.h"
 #include <gnuradio/blocks/file_sink.h>
 #include <gnuradio/msg_queue.h>
+#include <gflags/gflags.h>
 #include <glog/logging.h>
 #include <gn3s/gn3s_source_cc.h>
 #include "configuration_interface.h"
@@ -112,7 +113,7 @@ void Gn3sSignalSource::disconnect(gr::top_block_sptr top_block)
 
 gr::basic_block_sptr Gn3sSignalSource::get_left_block()
 {
-    LOG_AT_LEVEL(WARNING) << "Left block of a signal source should not be retrieved";
+    LOG(WARNING) << "Left block of a signal source should not be retrieved";
     return gr::block_sptr();
 }
 

src/algorithms/tracking/gnuradio_blocks/galileo_e1_dll_pll_veml_tracking_cc.cc

@@ -174,6 +174,11 @@ galileo_e1_dll_pll_veml_tracking_cc::galileo_e1_dll_pll_veml_tracking_cc(
     d_carrier_lock_threshold = CARRIER_LOCK_THRESHOLD;
 
     systemName["E"] = std::string("Galileo");
+    *d_Very_Early=gr_complex(0,0);
+    *d_Early=gr_complex(0,0);
+    *d_Prompt=gr_complex(0,0);
+    *d_Late=gr_complex(0,0);
+    *d_Very_Late=gr_complex(0,0);
 }
 
 void galileo_e1_dll_pll_veml_tracking_cc::start_tracking()
@@ -472,6 +477,23 @@ int galileo_e1_dll_pll_veml_tracking_cc::general_work (int noutput_items,gr_vect
         }
     else
     {
+    	// ########## DEBUG OUTPUT (TIME ONLY for channel 0 when tracking is disabled)
+    	/*!
+    	 *  \todo The stop timer has to be moved to the signal source!
+    	 */
+    	// stream to collect cout calls to improve thread safety
+    	std::stringstream tmp_str_stream;
+    	if (floor(d_sample_counter / d_fs_in) != d_last_seg)
+    	{
+    		d_last_seg = floor(d_sample_counter / d_fs_in);
+
+    		if (d_channel == 0)
+    		{
+    			// debug: Second counter in channel 0
+    			tmp_str_stream << "Current input signal time = " << d_last_seg << " [s]" << std::endl << std::flush;
+    			std::cout << tmp_str_stream.rdbuf() << std::flush;
+    		}
+    	}
     	*d_Early = gr_complex(0,0);
     	*d_Prompt = gr_complex(0,0);
     	*d_Late = gr_complex(0,0);

src/algorithms/tracking/gnuradio_blocks/galileo_e1_tcp_connector_tracking_cc.cc

@@ -489,6 +489,23 @@ int Galileo_E1_Tcp_Connector_Tracking_cc::general_work (int noutput_items, gr_ve
         }
     else
         {
+			// ########## DEBUG OUTPUT (TIME ONLY for channel 0 when tracking is disabled)
+			/*!
+			 *  \todo The stop timer has to be moved to the signal source!
+			 */
+			// stream to collect cout calls to improve thread safety
+			std::stringstream tmp_str_stream;
+			if (floor(d_sample_counter / d_fs_in) != d_last_seg)
+			{
+				d_last_seg = floor(d_sample_counter / d_fs_in);
+
+				if (d_channel == 0)
+				{
+					// debug: Second counter in channel 0
+					tmp_str_stream << "Current input signal time = " << d_last_seg << " [s]" << std::endl << std::flush;
+					std::cout << tmp_str_stream.rdbuf() << std::flush;
+				}
+			}
             *d_Early = gr_complex(0,0);
             *d_Prompt = gr_complex(0,0);
             *d_Late = gr_complex(0,0);

src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_fll_pll_tracking_cc.cc

@@ -540,6 +540,23 @@ int Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::general_work (int noutput_items, gr_vecto
         }
     else
         {
+			// ########## DEBUG OUTPUT (TIME ONLY for channel 0 when tracking is disabled)
+			/*!
+			 *  \todo The stop timer has to be moved to the signal source!
+			 */
+			// stream to collect cout calls to improve thread safety
+			std::stringstream tmp_str_stream;
+			if (floor(d_sample_counter / d_fs_in) != d_last_seg)
+			{
+				d_last_seg = floor(d_sample_counter / d_fs_in);
+
+				if (d_channel == 0)
+				{
+					// debug: Second counter in channel 0
+					tmp_str_stream << "Current input signal time = " << d_last_seg << " [s]" << std::endl << std::flush;
+					std::cout << tmp_str_stream.rdbuf() << std::flush;
+				}
+			}
             *d_Early  = gr_complex(0,0);
             *d_Prompt = gr_complex(0,0);
             *d_Late   = gr_complex(0,0);

src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_pll_optim_tracking_cc.cc

@@ -499,6 +499,24 @@ int Gps_L1_Ca_Dll_Pll_Optim_Tracking_cc::general_work (int noutput_items, gr_vec
         }
     else
         {
+
+			// ########## DEBUG OUTPUT (TIME ONLY for channel 0 when tracking is disabled)
+			/*!
+			 *  \todo The stop timer has to be moved to the signal source!
+			 */
+			// stream to collect cout calls to improve thread safety
+			std::stringstream tmp_str_stream;
+			if (floor(d_sample_counter / d_fs_in) != d_last_seg)
+			{
+				d_last_seg = floor(d_sample_counter / d_fs_in);
+
+				if (d_channel == 0)
+				{
+					// debug: Second counter in channel 0
+					tmp_str_stream << "Current input signal time = " << d_last_seg << " [s]" << std::endl << std::flush;
+					std::cout << tmp_str_stream.rdbuf() << std::flush;
+				}
+			}
             *d_Early = gr_complex(0,0);
             *d_Prompt = gr_complex(0,0);
             *d_Late = gr_complex(0,0);

src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_pll_tracking_cc.cc

@@ -515,6 +515,23 @@ int Gps_L1_Ca_Dll_Pll_Tracking_cc::general_work (int noutput_items, gr_vector_in
         }
     else
         {
+			// ########## DEBUG OUTPUT (TIME ONLY for channel 0 when tracking is disabled)
+			/*!
+			 *  \todo The stop timer has to be moved to the signal source!
+			 */
+			// stream to collect cout calls to improve thread safety
+			std::stringstream tmp_str_stream;
+			if (floor(d_sample_counter / d_fs_in) != d_last_seg)
+			{
+				d_last_seg = floor(d_sample_counter / d_fs_in);
+
+				if (d_channel == 0)
+				{
+					// debug: Second counter in channel 0
+					tmp_str_stream << "Current input signal time = " << d_last_seg << " [s]" << std::endl << std::flush;
+					std::cout << tmp_str_stream.rdbuf() << std::flush;
+				}
+			}
             *d_Early = gr_complex(0,0);
             *d_Prompt = gr_complex(0,0);
             *d_Late = gr_complex(0,0);

src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_tcp_connector_tracking_cc.cc

@@ -558,6 +558,23 @@ int Gps_L1_Ca_Tcp_Connector_Tracking_cc::general_work (int noutput_items, gr_vec
         }
     else
         {
+			// ########## DEBUG OUTPUT (TIME ONLY for channel 0 when tracking is disabled)
+			/*!
+			 *  \todo The stop timer has to be moved to the signal source!
+			 */
+			// stream to collect cout calls to improve thread safety
+			std::stringstream tmp_str_stream;
+			if (floor(d_sample_counter / d_fs_in) != d_last_seg)
+			{
+				d_last_seg = floor(d_sample_counter / d_fs_in);
+
+				if (d_channel == 0)
+				{
+					// debug: Second counter in channel 0
+					tmp_str_stream << "Current input signal time = " << d_last_seg << " [s]" << std::endl << std::flush;
+					std::cout << tmp_str_stream.rdbuf() << std::flush;
+				}
+			}
             *d_Early = gr_complex(0,0);
             *d_Prompt = gr_complex(0,0);
             *d_Late = gr_complex(0,0);