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/*!
* \ file gps_l1_ca_tcp_connector_tracking_cc . cc
* \ brief Implementation of a TCP connector block based on Code DLL + carrier PLL
* \ author David Pubill , 2012. dpubill ( at ) cttc . es
* Javier Arribas , 2011. jarribas ( at ) cttc . es
*
*
* Code DLL + carrier PLL according to the algorithms described in :
* [ 1 ] K . Borre , D . M . Akos , N . Bertelsen , P . Rinder , and S . H . Jensen ,
* A Software - Defined GPS and Galileo Receiver . A Single - Frequency
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* Approach , Birkhauser , 2007
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*
* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
*
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* Copyright ( C ) 2010 - 2015 ( see AUTHORS file for a list of contributors )
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*
* 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
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* ( at your option ) any later version .
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*
* 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 "gps_l1_ca_tcp_connector_tracking_cc.h"
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# include <cmath>
# include <iostream>
# include <sstream>
# include <boost/asio.hpp>
# include <boost/lexical_cast.hpp>
# include <gnuradio/io_signature.h>
# include <glog/logging.h>
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# include <volk_gnsssdr/volk_gnsssdr.h>
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# include "gps_sdr_signal_processing.h"
# include "tracking_discriminators.h"
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# include "lock_detectors.h"
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# include "GPS_L1_CA.h"
# include "control_message_factory.h"
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# include "gnss_sdr_flags.h"
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# include "tcp_communication.h"
# include "tcp_packet_data.h"
using google : : LogMessage ;
gps_l1_ca_tcp_connector_tracking_cc_sptr
gps_l1_ca_tcp_connector_make_tracking_cc (
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long if_freq ,
long fs_in ,
unsigned int vector_length ,
bool dump ,
std : : string dump_filename ,
float early_late_space_chips ,
size_t port_ch0 )
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{
return gps_l1_ca_tcp_connector_tracking_cc_sptr ( new Gps_L1_Ca_Tcp_Connector_Tracking_cc ( if_freq ,
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fs_in , vector_length , dump , dump_filename , early_late_space_chips , port_ch0 ) ) ;
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}
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void Gps_L1_Ca_Tcp_Connector_Tracking_cc : : forecast ( int noutput_items ,
gr_vector_int & ninput_items_required )
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{
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if ( noutput_items ! = 0 )
{
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ninput_items_required [ 0 ] = static_cast < int > ( d_vector_length ) * 2 ; //set the required available samples in each call
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}
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}
Gps_L1_Ca_Tcp_Connector_Tracking_cc : : Gps_L1_Ca_Tcp_Connector_Tracking_cc (
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long if_freq ,
long fs_in ,
unsigned int vector_length ,
bool dump ,
std : : string dump_filename ,
float early_late_space_chips ,
size_t port_ch0 ) : gr : : block ( " Gps_L1_Ca_Tcp_Connector_Tracking_cc " , gr : : io_signature : : make ( 1 , 1 , sizeof ( gr_complex ) ) ,
gr : : io_signature : : make ( 1 , 1 , sizeof ( Gnss_Synchro ) ) )
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{
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// Telemetry bit synchronization message port input
this - > message_port_register_in ( pmt : : mp ( " preamble_timestamp_s " ) ) ;
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this - > message_port_register_out ( pmt : : mp ( " events " ) ) ;
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// initialize internal vars
d_dump = dump ;
d_if_freq = if_freq ;
d_fs_in = fs_in ;
d_vector_length = vector_length ;
d_dump_filename = dump_filename ;
//--- DLL variables --------------------------------------------------------
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d_early_late_spc_chips = early_late_space_chips ; // Define early-late offset (in chips)
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//--- TCP CONNECTOR variables --------------------------------------------------------
d_port_ch0 = port_ch0 ;
d_port = 0 ;
d_listen_connection = true ;
d_control_id = 0 ;
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// Initialization of local code replica
// Get space for a vector with the C/A code replica sampled 1x/chip
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d_ca_code = static_cast < gr_complex * > ( volk_gnsssdr_malloc ( ( GPS_L1_CA_CODE_LENGTH_CHIPS ) * sizeof ( gr_complex ) , volk_gnsssdr_get_alignment ( ) ) ) ;
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// correlator outputs (scalar)
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d_n_correlator_taps = 3 ; // Very-Early, Early, Prompt, Late, Very-Late
d_correlator_outs = static_cast < gr_complex * > ( volk_gnsssdr_malloc ( d_n_correlator_taps * sizeof ( gr_complex ) , volk_gnsssdr_get_alignment ( ) ) ) ;
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for ( int n = 0 ; n < d_n_correlator_taps ; n + + )
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{
d_correlator_outs [ n ] = gr_complex ( 0 , 0 ) ;
}
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// map memory pointers of correlator outputs
d_Early = & d_correlator_outs [ 0 ] ;
d_Prompt = & d_correlator_outs [ 1 ] ;
d_Late = & d_correlator_outs [ 2 ] ;
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d_local_code_shift_chips = static_cast < float * > ( volk_gnsssdr_malloc ( d_n_correlator_taps * sizeof ( float ) , volk_gnsssdr_get_alignment ( ) ) ) ;
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// Set TAPs delay values [chips]
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d_local_code_shift_chips [ 0 ] = - d_early_late_spc_chips ;
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d_local_code_shift_chips [ 1 ] = 0.0 ;
d_local_code_shift_chips [ 2 ] = d_early_late_spc_chips ;
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d_correlation_length_samples = d_vector_length ;
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multicorrelator_cpu . init ( 2 * d_correlation_length_samples , d_n_correlator_taps ) ;
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//--- Perform initializations ------------------------------
// define initial code frequency basis of NCO
d_code_freq_hz = GPS_L1_CA_CODE_RATE_HZ ;
// define residual code phase (in chips)
d_rem_code_phase_samples = 0.0 ;
// define residual carrier phase
d_rem_carr_phase_rad = 0.0 ;
// sample synchronization
d_sample_counter = 0 ;
d_sample_counter_seconds = 0 ;
d_acq_sample_stamp = 0 ;
d_enable_tracking = false ;
d_pull_in = false ;
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d_current_prn_length_samples = static_cast < int > ( d_vector_length ) ;
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// CN0 estimation and lock detector buffers
d_cn0_estimation_counter = 0 ;
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d_Prompt_buffer = new gr_complex [ FLAGS_cn0_samples ] ;
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d_carrier_lock_test = 1 ;
d_CN0_SNV_dB_Hz = 0 ;
d_carrier_lock_fail_counter = 0 ;
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d_carrier_lock_threshold = FLAGS_carrier_lock_th ;
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systemName [ " G " ] = std : : string ( " GPS " ) ;
systemName [ " R " ] = std : : string ( " GLONASS " ) ;
systemName [ " S " ] = std : : string ( " SBAS " ) ;
systemName [ " E " ] = std : : string ( " Galileo " ) ;
systemName [ " C " ] = std : : string ( " Compass " ) ;
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d_acquisition_gnss_synchro = 0 ;
d_channel = 0 ;
d_next_rem_code_phase_samples = 0 ;
d_acq_code_phase_samples = 0.0 ;
d_acq_carrier_doppler_hz = 0.0 ;
d_carrier_doppler_hz = 0.0 ;
d_acc_carrier_phase_rad = 0.0 ;
d_code_phase_samples = 0 ;
d_next_prn_length_samples = 0 ;
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d_code_phase_step_chips = 0.0 ;
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}
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void Gps_L1_Ca_Tcp_Connector_Tracking_cc : : start_tracking ( )
{
/*
* correct the code phase according to the delay between acq and trk
*/
d_acq_code_phase_samples = d_acquisition_gnss_synchro - > Acq_delay_samples ;
d_acq_carrier_doppler_hz = d_acquisition_gnss_synchro - > Acq_doppler_hz ;
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d_acq_sample_stamp = d_acquisition_gnss_synchro - > Acq_samplestamp_samples ;
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long int acq_trk_diff_samples ;
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float acq_trk_diff_seconds ;
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acq_trk_diff_samples = static_cast < long int > ( d_sample_counter ) - static_cast < long int > ( d_acq_sample_stamp ) ;
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std : : cout < < " acq_trk_diff_samples= " < < acq_trk_diff_samples < < std : : endl ;
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acq_trk_diff_seconds = static_cast < float > ( acq_trk_diff_samples ) / static_cast < float > ( d_fs_in ) ;
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//doppler effect
// Fd=(C/(C+Vr))*F
float radial_velocity ;
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radial_velocity = ( GPS_L1_FREQ_HZ + d_acq_carrier_doppler_hz ) / GPS_L1_FREQ_HZ ;
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// new chip and prn sequence periods based on acq Doppler
float T_chip_mod_seconds ;
float T_prn_mod_seconds ;
float T_prn_mod_samples ;
d_code_freq_hz = radial_velocity * GPS_L1_CA_CODE_RATE_HZ ;
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d_code_phase_step_chips = static_cast < double > ( d_code_freq_hz ) / static_cast < double > ( d_fs_in ) ;
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T_chip_mod_seconds = 1 / d_code_freq_hz ;
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T_prn_mod_seconds = T_chip_mod_seconds * GPS_L1_CA_CODE_LENGTH_CHIPS ;
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T_prn_mod_samples = T_prn_mod_seconds * static_cast < float > ( d_fs_in ) ;
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d_next_prn_length_samples = round ( T_prn_mod_samples ) ;
float T_prn_true_seconds = GPS_L1_CA_CODE_LENGTH_CHIPS / GPS_L1_CA_CODE_RATE_HZ ;
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float T_prn_true_samples = T_prn_true_seconds * static_cast < float > ( d_fs_in ) ;
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float T_prn_diff_seconds ;
T_prn_diff_seconds = T_prn_true_seconds - T_prn_mod_seconds ;
float N_prn_diff ;
N_prn_diff = acq_trk_diff_seconds / T_prn_true_seconds ;
float corrected_acq_phase_samples , delay_correction_samples ;
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corrected_acq_phase_samples = fmod ( ( d_acq_code_phase_samples + T_prn_diff_seconds * N_prn_diff * static_cast < float > ( d_fs_in ) ) , T_prn_true_samples ) ;
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if ( corrected_acq_phase_samples < 0 )
{
corrected_acq_phase_samples = T_prn_mod_samples + corrected_acq_phase_samples ;
}
delay_correction_samples = d_acq_code_phase_samples - corrected_acq_phase_samples ;
d_acq_code_phase_samples = corrected_acq_phase_samples ;
d_carrier_doppler_hz = d_acq_carrier_doppler_hz ;
// generate local reference ALWAYS starting at chip 1 (1 sample per chip)
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gps_l1_ca_code_gen_complex ( d_ca_code , d_acquisition_gnss_synchro - > PRN , 0 ) ;
multicorrelator_cpu . set_local_code_and_taps ( static_cast < int > ( GPS_L1_CA_CODE_LENGTH_CHIPS ) , d_ca_code , d_local_code_shift_chips ) ;
for ( int n = 0 ; n < d_n_correlator_taps ; n + + )
{
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d_correlator_outs [ n ] = gr_complex ( 0 , 0 ) ;
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}
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d_carrier_lock_fail_counter = 0 ;
d_rem_code_phase_samples = 0 ;
d_rem_carr_phase_rad = 0 ;
d_rem_code_phase_samples = 0 ;
d_next_rem_code_phase_samples = 0 ;
d_acc_carrier_phase_rad = 0 ;
d_code_phase_samples = d_acq_code_phase_samples ;
std : : string sys_ = & d_acquisition_gnss_synchro - > System ;
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sys = sys_ . substr ( 0 , 1 ) ;
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// DEBUG OUTPUT
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std : : cout < < " Tracking of GPS L1 C/A signal started on channel " < < d_channel < < " for satellite " < < Gnss_Satellite ( systemName [ sys ] , d_acquisition_gnss_synchro - > PRN ) < < std : : endl ;
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LOG ( INFO ) < < " Starting tracking of satellite " < < Gnss_Satellite ( systemName [ sys ] , d_acquisition_gnss_synchro - > PRN ) < < " on channel " < < d_channel ;
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// enable tracking
d_pull_in = true ;
d_enable_tracking = true ;
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LOG ( INFO ) < < " PULL-IN Doppler [Hz]= " < < d_carrier_doppler_hz
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< < " Code Phase correction [samples]= " < < delay_correction_samples
< < " PULL-IN Code Phase [samples]= " < < d_acq_code_phase_samples ;
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}
Gps_L1_Ca_Tcp_Connector_Tracking_cc : : ~ Gps_L1_Ca_Tcp_Connector_Tracking_cc ( )
{
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if ( d_dump_file . is_open ( ) )
{
try
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{
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d_dump_file . close ( ) ;
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}
catch ( const std : : exception & ex )
{
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LOG ( WARNING ) < < " Exception in destructor " < < ex . what ( ) ;
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}
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}
try
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{
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volk_gnsssdr_free ( d_local_code_shift_chips ) ;
volk_gnsssdr_free ( d_correlator_outs ) ;
volk_gnsssdr_free ( d_ca_code ) ;
d_tcp_com . close_tcp_connection ( d_port ) ;
delete [ ] d_Prompt_buffer ;
multicorrelator_cpu . free ( ) ;
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}
catch ( const std : : exception & ex )
{
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LOG ( WARNING ) < < " Exception in destructor " < < ex . what ( ) ;
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}
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}
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int Gps_L1_Ca_Tcp_Connector_Tracking_cc : : 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 )
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{
// process vars
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float carr_error = 0.0 ;
float code_error = 0.0 ;
float code_nco = 0.0 ;
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tcp_packet_data tcp_data ;
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// GNSS_SYNCHRO OBJECT to interchange data between tracking->telemetry_decoder
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Gnss_Synchro current_synchro_data = Gnss_Synchro ( ) ;
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// Block input data and block output stream pointers
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const gr_complex * in = reinterpret_cast < const gr_complex * > ( input_items [ 0 ] ) ;
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Gnss_Synchro * * out = reinterpret_cast < Gnss_Synchro * * > ( & output_items [ 0 ] ) ;
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if ( d_enable_tracking = = true )
{
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// Fill the acquisition data
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current_synchro_data = * d_acquisition_gnss_synchro ;
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/*
* Receiver signal alignment
*/
if ( d_pull_in = = true )
{
int samples_offset ;
// 28/11/2011 ACQ to TRK transition BUG CORRECTION
float acq_trk_shif_correction_samples ;
int acq_to_trk_delay_samples ;
acq_to_trk_delay_samples = d_sample_counter - d_acq_sample_stamp ;
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acq_trk_shif_correction_samples = d_next_prn_length_samples - fmod ( static_cast < float > ( acq_to_trk_delay_samples ) , static_cast < float > ( d_next_prn_length_samples ) ) ;
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samples_offset = round ( d_acq_code_phase_samples + acq_trk_shif_correction_samples ) ;
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current_synchro_data . Tracking_sample_counter = d_sample_counter + samples_offset ;
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current_synchro_data . fs = d_fs_in ;
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* out [ 0 ] = current_synchro_data ;
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d_sample_counter_seconds = d_sample_counter_seconds + ( static_cast < double > ( samples_offset ) / static_cast < double > ( d_fs_in ) ) ;
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d_sample_counter = d_sample_counter + samples_offset ; //count for the processed samples
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d_pull_in = false ;
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consume_each ( samples_offset ) ; //shift input to perform alignment with local replica
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return 1 ;
}
// Update the prn length based on code freq (variable) and
// sampling frequency (fixed)
// variable code PRN sample block size
d_current_prn_length_samples = d_next_prn_length_samples ;
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// ################# CARRIER WIPEOFF AND CORRELATORS ##############################
// perform carrier wipe-off and compute Early, Prompt and Late correlation
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multicorrelator_cpu . set_input_output_vectors ( d_correlator_outs , in ) ;
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double carr_phase_step_rad = GPS_TWO_PI * d_carrier_doppler_hz / static_cast < double > ( d_fs_in ) ;
double rem_code_phase_chips = d_rem_code_phase_samples * ( d_code_freq_hz / d_fs_in ) ;
multicorrelator_cpu . Carrier_wipeoff_multicorrelator_resampler ( d_rem_carr_phase_rad ,
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carr_phase_step_rad ,
rem_code_phase_chips ,
d_code_phase_step_chips ,
d_current_prn_length_samples ) ;
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//! Variable used for control
d_control_id + + ;
//! Send and receive a TCP packet
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boost : : array < float , NUM_TX_VARIABLES_GPS_L1_CA > tx_variables_array = { { d_control_id ,
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( * d_Early ) . real ( ) ,
( * d_Early ) . imag ( ) ,
( * d_Late ) . real ( ) ,
( * d_Late ) . imag ( ) ,
( * d_Prompt ) . real ( ) ,
( * d_Prompt ) . imag ( ) ,
d_acq_carrier_doppler_hz ,
1 } } ;
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d_tcp_com . send_receive_tcp_packet_gps_l1_ca ( tx_variables_array , & tcp_data ) ;
//! Recover the tracking data
code_error = tcp_data . proc_pack_code_error ;
carr_error = tcp_data . proc_pack_carr_error ;
// Modify carrier freq based on NCO command
d_carrier_doppler_hz = tcp_data . proc_pack_carrier_doppler_hz ;
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// Modify code freq based on NCO command
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code_nco = 1 / ( 1 / GPS_L1_CA_CODE_RATE_HZ - code_error / GPS_L1_CA_CODE_LENGTH_CHIPS ) ;
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d_code_freq_hz = code_nco ;
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// Update the phasestep based on code freq (variable) and
// sampling frequency (fixed)
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d_code_phase_step_chips = d_code_freq_hz / static_cast < float > ( d_fs_in ) ; //[chips]
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// variable code PRN sample block size
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double T_chip_seconds ;
double T_prn_seconds ;
double T_prn_samples ;
double K_blk_samples ;
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T_chip_seconds = 1.0 / static_cast < double > ( d_code_freq_hz ) ;
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T_prn_seconds = T_chip_seconds * GPS_L1_CA_CODE_LENGTH_CHIPS ;
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T_prn_samples = T_prn_seconds * static_cast < double > ( d_fs_in ) ;
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d_rem_code_phase_samples = d_next_rem_code_phase_samples ;
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K_blk_samples = T_prn_samples + d_rem_code_phase_samples ; //-code_error*(double)d_fs_in;
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// Update the current PRN delay (code phase in samples)
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double T_prn_true_seconds = GPS_L1_CA_CODE_LENGTH_CHIPS / GPS_L1_CA_CODE_RATE_HZ ;
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double T_prn_true_samples = T_prn_true_seconds * static_cast < double > ( d_fs_in ) ;
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d_code_phase_samples = d_code_phase_samples + T_prn_samples - T_prn_true_samples ;
if ( d_code_phase_samples < 0 )
{
d_code_phase_samples = T_prn_true_samples + d_code_phase_samples ;
}
d_code_phase_samples = fmod ( d_code_phase_samples , T_prn_true_samples ) ;
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d_next_prn_length_samples = round ( K_blk_samples ) ; //round to a discrete samples
d_next_rem_code_phase_samples = K_blk_samples - d_next_prn_length_samples ; //rounding error
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/*!
* \ todo Improve the lock detection algorithm !
*/
// ####### CN0 ESTIMATION AND LOCK DETECTORS ######
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if ( d_cn0_estimation_counter < FLAGS_cn0_samples )
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{
// fill buffer with prompt correlator output values
d_Prompt_buffer [ d_cn0_estimation_counter ] = * d_Prompt ;
d_cn0_estimation_counter + + ;
}
else
{
d_cn0_estimation_counter = 0 ;
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d_CN0_SNV_dB_Hz = cn0_svn_estimator ( d_Prompt_buffer , FLAGS_cn0_samples , d_fs_in , GPS_L1_CA_CODE_LENGTH_CHIPS ) ;
d_carrier_lock_test = carrier_lock_detector ( d_Prompt_buffer , FLAGS_cn0_samples ) ;
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// ###### TRACKING UNLOCK NOTIFICATION #####
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if ( d_carrier_lock_test < d_carrier_lock_threshold or d_CN0_SNV_dB_Hz < FLAGS_cn0_min )
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{
d_carrier_lock_fail_counter + + ;
}
else
{
if ( d_carrier_lock_fail_counter > 0 ) d_carrier_lock_fail_counter - - ;
}
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if ( d_carrier_lock_fail_counter > FLAGS_max_lock_fail )
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{
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std : : cout < < " Loss of lock in channel " < < d_channel < < " ! " < < std : : endl ;
LOG ( INFO ) < < " Loss of lock in channel " < < d_channel < < " ! " ;
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this - > message_port_pub ( pmt : : mp ( " events " ) , pmt : : from_long ( 3 ) ) ; //3 -> loss of lock
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d_carrier_lock_fail_counter = 0 ;
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d_enable_tracking = false ; // TODO: check if disabling tracking is consistent with the channel state machine
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}
}
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// ########### Output the tracking data to navigation and PVT ##########
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current_synchro_data . Prompt_I = static_cast < double > ( ( * d_Prompt ) . real ( ) ) ;
current_synchro_data . Prompt_Q = static_cast < double > ( ( * d_Prompt ) . imag ( ) ) ;
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//compute remnant code phase samples AFTER the Tracking timestamp
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d_rem_code_phase_samples = K_blk_samples - d_current_prn_length_samples ; //rounding error < 1 sample
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current_synchro_data . Tracking_sample_counter = d_sample_counter + d_current_prn_length_samples ;
current_synchro_data . Code_phase_samples = d_rem_code_phase_samples ;
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current_synchro_data . Carrier_phase_rads = static_cast < double > ( d_acc_carrier_phase_rad ) ;
current_synchro_data . Carrier_Doppler_hz = static_cast < double > ( d_carrier_doppler_hz ) ;
current_synchro_data . CN0_dB_hz = static_cast < double > ( d_CN0_SNV_dB_Hz ) ;
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current_synchro_data . Flag_valid_symbol_output = true ;
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current_synchro_data . correlation_length_ms = 1 ;
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}
else
{
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* d_Early = gr_complex ( 0 , 0 ) ;
* d_Prompt = gr_complex ( 0 , 0 ) ;
* d_Late = gr_complex ( 0 , 0 ) ;
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// GNSS_SYNCHRO OBJECT to interchange data between tracking->telemetry_decoder
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current_synchro_data . Tracking_sample_counter = d_sample_counter + d_correlation_length_samples ;
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//! When tracking is disabled an array of 1's is sent to maintain the TCP connection
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boost : : array < float , NUM_TX_VARIABLES_GPS_L1_CA > tx_variables_array = { { 1 , 1 , 1 , 1 , 1 , 1 , 1 , 1 , 0 } } ;
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d_tcp_com . send_receive_tcp_packet_gps_l1_ca ( tx_variables_array , & tcp_data ) ;
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}
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//assign the GNURadio block output data
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current_synchro_data . System = { ' G ' } ;
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std : : string str_aux = " 1C " ;
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const char * str = str_aux . c_str ( ) ; // get a C style null terminated string
std : : memcpy ( static_cast < void * > ( current_synchro_data . Signal ) , str , 3 ) ;
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current_synchro_data . fs = d_fs_in ;
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* out [ 0 ] = current_synchro_data ;
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if ( d_dump )
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{
// MULTIPLEXED FILE RECORDING - Record results to file
float prompt_I ;
float prompt_Q ;
float tmp_E , tmp_P , tmp_L ;
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float tmp_VE = 0.0 ;
float tmp_VL = 0.0 ;
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float tmp_float ;
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prompt_I = d_correlator_outs [ 1 ] . real ( ) ;
prompt_Q = d_correlator_outs [ 1 ] . imag ( ) ;
tmp_E = std : : abs < float > ( d_correlator_outs [ 0 ] ) ;
tmp_P = std : : abs < float > ( d_correlator_outs [ 1 ] ) ;
tmp_L = std : : abs < float > ( d_correlator_outs [ 2 ] ) ;
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try
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{
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// Dump correlators output
d_dump_file . write ( reinterpret_cast < char * > ( & tmp_VE ) , sizeof ( float ) ) ;
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d_dump_file . write ( reinterpret_cast < char * > ( & tmp_E ) , sizeof ( float ) ) ;
d_dump_file . write ( reinterpret_cast < char * > ( & tmp_P ) , sizeof ( float ) ) ;
d_dump_file . write ( reinterpret_cast < char * > ( & tmp_L ) , sizeof ( float ) ) ;
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d_dump_file . write ( reinterpret_cast < char * > ( & tmp_VL ) , sizeof ( float ) ) ;
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// PROMPT I and Q (to analyze navigation symbols)
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d_dump_file . write ( reinterpret_cast < char * > ( & prompt_I ) , sizeof ( float ) ) ;
d_dump_file . write ( reinterpret_cast < char * > ( & prompt_Q ) , sizeof ( float ) ) ;
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// PRN start sample stamp
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d_dump_file . write ( reinterpret_cast < char * > ( & d_sample_counter ) , sizeof ( unsigned long int ) ) ;
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// accumulated carrier phase
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tmp_float = d_acc_carrier_phase_rad ;
d_dump_file . write ( reinterpret_cast < char * > ( & tmp_float ) , sizeof ( float ) ) ;
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// carrier and code frequency
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tmp_float = d_carrier_doppler_hz ;
d_dump_file . write ( reinterpret_cast < char * > ( & tmp_float ) , sizeof ( float ) ) ;
tmp_float = d_code_freq_hz ;
d_dump_file . write ( reinterpret_cast < char * > ( & tmp_float ) , sizeof ( float ) ) ;
// PLL commands
tmp_float = 0.0 ;
d_dump_file . write ( reinterpret_cast < char * > ( & tmp_float ) , sizeof ( float ) ) ;
tmp_float = carr_error ;
d_dump_file . write ( reinterpret_cast < char * > ( & tmp_float ) , sizeof ( float ) ) ;
// DLL commands
tmp_float = 0.0 ;
d_dump_file . write ( reinterpret_cast < char * > ( & tmp_float ) , sizeof ( float ) ) ;
tmp_float = code_error ;
d_dump_file . write ( reinterpret_cast < char * > ( & tmp_float ) , sizeof ( float ) ) ;
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// CN0 and carrier lock test
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tmp_float = d_CN0_SNV_dB_Hz ;
d_dump_file . write ( reinterpret_cast < char * > ( & tmp_float ) , sizeof ( float ) ) ;
tmp_float = d_carrier_lock_test ;
d_dump_file . write ( reinterpret_cast < char * > ( & tmp_float ) , sizeof ( float ) ) ;
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// AUX vars (for debug purposes)
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tmp_float = 0.0 ;
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d_dump_file . write ( reinterpret_cast < char * > ( & tmp_float ) , sizeof ( float ) ) ;
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double tmp_double = static_cast < double > ( d_sample_counter + d_correlation_length_samples ) ;
d_dump_file . write ( reinterpret_cast < char * > ( & tmp_double ) , sizeof ( double ) ) ;
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// PRN
unsigned int prn_ = d_acquisition_gnss_synchro - > PRN ;
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d_dump_file . write ( reinterpret_cast < char * > ( & prn_ ) , sizeof ( unsigned int ) ) ;
}
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catch ( const std : : ifstream : : failure & e )
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{
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LOG ( WARNING ) < < " Exception writing trk dump file " < < e . what ( ) ;
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}
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}
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consume_each ( d_current_prn_length_samples ) ; // this is necessary in gr::block derivates
d_sample_counter_seconds = d_sample_counter_seconds + ( static_cast < double > ( d_current_prn_length_samples ) / static_cast < double > ( d_fs_in ) ) ;
d_sample_counter + = d_current_prn_length_samples ; //count for the processed samples
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if ( d_enable_tracking )
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{
return 1 ;
}
else
{
return 0 ;
}
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}
void Gps_L1_Ca_Tcp_Connector_Tracking_cc : : set_channel ( unsigned int channel )
{
d_channel = channel ;
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LOG ( INFO ) < < " Tracking Channel set to " < < d_channel ;
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// ############# ENABLE DATA FILE LOG #################
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if ( d_dump = = true )
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{
if ( d_dump_file . is_open ( ) = = false )
{
try
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{
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d_dump_filename . append ( boost : : lexical_cast < std : : string > ( d_channel ) ) ;
d_dump_filename . append ( " .dat " ) ;
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d_dump_file . exceptions ( std : : ifstream : : failbit | std : : ifstream : : badbit ) ;
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d_dump_file . open ( d_dump_filename . c_str ( ) , std : : ios : : out | std : : ios : : binary ) ;
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LOG ( INFO ) < < " Tracking dump enabled on channel " < < d_channel < < " Log file: " < < d_dump_filename . c_str ( ) ;
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}
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catch ( const std : : ifstream : : failure & e )
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{
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LOG ( WARNING ) < < " channel " < < d_channel < < " Exception opening trk dump file " < < e . what ( ) ;
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}
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}
}
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//! Listen for connections on a TCP port
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if ( d_listen_connection = = true )
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{
d_port = d_port_ch0 + d_channel ;
d_listen_connection = d_tcp_com . listen_tcp_connection ( d_port , d_port_ch0 ) ;
}
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}
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void Gps_L1_Ca_Tcp_Connector_Tracking_cc : : set_gnss_synchro ( Gnss_Synchro * p_gnss_synchro )
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{
d_acquisition_gnss_synchro = p_gnss_synchro ;
}