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Code Issues Releases Wiki Activity

Experimental extended correlation for GPS L1 CA C_Aid tracking

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This commit is contained in:
Javier Arribas
2016-03-08 18:30:56 +01:00
parent 59011a7772
commit d664dc63b3
8 changed files with 319 additions and 134 deletions
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325
src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_pll_c_aid_tracking_cc.cc
View File

@@ -34,7 +34,9 @@
#include <memory>
#include <sstream>
#include <boost/lexical_cast.hpp>
#include <boost/bind.hpp>
#include <gnuradio/io_signature.h>
#include <pmt/pmt.h>
#include <volk/volk.h>
#include <glog/logging.h>
#include "gps_sdr_signal_processing.h"
@@ -82,6 +84,17 @@ void gps_l1_ca_dll_pll_c_aid_tracking_cc::forecast (int noutput_items,
}
}
void gps_l1_ca_dll_pll_c_aid_tracking_cc::msg_handler_preamble_index(pmt::pmt_t msg)
{
//pmt::print(msg);
DLOG(INFO) << "Extended correlation for Tracking CH " << d_channel << ": Satellite " << Gnss_Satellite(systemName[sys], d_acquisition_gnss_synchro->PRN)<< std::endl;
if (d_enable_20ms_integration==false) //avoid re-setting preamble indicator
{
d_preamble_index=pmt::to_long(msg);
d_enable_20ms_integration=true;
d_preamble_synchronized=false;
}
}
gps_l1_ca_dll_pll_c_aid_tracking_cc::gps_l1_ca_dll_pll_c_aid_tracking_cc(
@@ -97,6 +110,13 @@ gps_l1_ca_dll_pll_c_aid_tracking_cc::gps_l1_ca_dll_pll_c_aid_tracking_cc(
gr::block("gps_l1_ca_dll_pll_c_aid_tracking_cc", gr::io_signature::make(1, 1, sizeof(gr_complex)),
gr::io_signature::make(1, 1, sizeof(Gnss_Synchro)))
{
// create asynchronous message ports
this->message_port_register_in(pmt::mp("preamble_index"));
this->set_msg_handler(pmt::mp("preamble_index"),
boost::bind(&gps_l1_ca_dll_pll_c_aid_tracking_cc::msg_handler_preamble_index, this, _1));
// initialize internal vars
d_queue = queue;
d_dump = dump;
@@ -107,8 +127,10 @@ gps_l1_ca_dll_pll_c_aid_tracking_cc::gps_l1_ca_dll_pll_c_aid_tracking_cc(
d_correlation_length_samples = static_cast<int>(d_vector_length);
// Initialize tracking ==========================================
d_code_loop_filter.set_DLL_BW(dll_bw_hz);
d_carrier_loop_filter.set_params(10.0, pll_bw_hz,2);
d_pll_bw_hz=pll_bw_hz;
d_dll_bw_hz=dll_bw_hz;
d_code_loop_filter.set_DLL_BW(d_dll_bw_hz);
d_carrier_loop_filter.set_params(10.0, d_pll_bw_hz,2);
//--- DLL variables --------------------------------------------------------
d_early_late_spc_chips = early_late_space_chips; // Define early-late offset (in chips)
@@ -141,7 +163,9 @@ gps_l1_ca_dll_pll_c_aid_tracking_cc::gps_l1_ca_dll_pll_c_aid_tracking_cc(
d_rem_carrier_phase_rad = 0.0;
// sample synchronization
d_sample_counter = 0;
d_sample_counter = 0; //(from trk to tlm)
// symbol synchronization (from tlm to trk)
d_symbol_counter =0;
//d_sample_counter_seconds = 0;
d_acq_sample_stamp = 0;
@@ -175,6 +199,8 @@ gps_l1_ca_dll_pll_c_aid_tracking_cc::gps_l1_ca_dll_pll_c_aid_tracking_cc(
d_rem_code_phase_chips = 0.0;
d_code_phase_step_chips = 0.0;
d_carrier_phase_step_rad = 0.0;
d_enable_20ms_integration=false;
d_preamble_synchronized=false;
//set_min_output_buffer((long int)300);
}
@@ -258,7 +284,8 @@ void gps_l1_ca_dll_pll_c_aid_tracking_cc::start_tracking()
// enable tracking
d_pull_in = true;
d_enable_tracking = true;
d_enable_20ms_integration=false;
d_preamble_synchronized=false;
LOG(INFO) << "PULL-IN Doppler [Hz]=" << d_carrier_doppler_hz
<< " Code Phase correction [samples]=" << delay_correction_samples
<< " PULL-IN Code Phase [samples]=" << d_acq_code_phase_samples;
@@ -315,6 +342,7 @@ int gps_l1_ca_dll_pll_c_aid_tracking_cc::general_work (int noutput_items, gr_vec
current_synchro_data = *d_acquisition_gnss_synchro;
*out[0] = current_synchro_data;
consume_each(samples_offset); //shift input to perform alignment with local replica
d_symbol_counter++;
return 1;
}
@@ -326,115 +354,203 @@ int gps_l1_ca_dll_pll_c_aid_tracking_cc::general_work (int noutput_items, gr_vec
multicorrelator_cpu.set_input_output_vectors(d_correlator_outs,in);
multicorrelator_cpu.Carrier_wipeoff_multicorrelator_resampler(d_rem_carrier_phase_rad, d_carrier_phase_step_rad, d_rem_code_phase_chips, d_code_phase_step_chips, d_correlation_length_samples);
// UPDATE INTEGRATION TIME
CURRENT_INTEGRATION_TIME_S = static_cast<double>(d_correlation_length_samples) / static_cast<double>(d_fs_in);
// ####### 20ms coherent intergration extension (experimental)
// keep the last 40 symbols (2 bits to detect transitions)
d_E_history.push_back(d_correlator_outs[0]); // save early output
d_P_history.push_back(d_correlator_outs[1]); // save prompt output
d_L_history.push_back(d_correlator_outs[2]); // save late output
// ################## PLL ##########################################################
// Update PLL discriminator [rads/Ti -> Secs/Ti]
carr_phase_error_secs_Ti = pll_cloop_two_quadrant_atan(d_correlator_outs[1]) / GPS_TWO_PI; //prompt output
// Carrier discriminator filter
// NOTICE: The carrier loop filter includes the Carrier Doppler accumulator, as described in Kaplan
//d_carrier_doppler_hz = d_acq_carrier_doppler_hz + carr_phase_error_filt_secs_ti/INTEGRATION_TIME;
// Input [s/Ti] -> output [Hz]
d_carrier_doppler_hz = d_carrier_loop_filter.get_carrier_error(0.0, carr_phase_error_secs_Ti, CURRENT_INTEGRATION_TIME_S);
// PLL to DLL assistance [Secs/Ti]
d_pll_to_dll_assist_secs_Ti = (d_carrier_doppler_hz * CURRENT_INTEGRATION_TIME_S) / GPS_L1_FREQ_HZ;
// code Doppler frequency update
d_code_freq_chips = GPS_L1_CA_CODE_RATE_HZ + ((d_carrier_doppler_hz * GPS_L1_CA_CODE_RATE_HZ) / GPS_L1_FREQ_HZ);
if (d_P_history.size()>GPS_CA_TELEMETRY_SYMBOLS_PER_BIT)
{
d_E_history.pop_front();
d_P_history.pop_front();
d_L_history.pop_front();
}
// ################## DLL ##########################################################
// DLL discriminator
code_error_chips_Ti = dll_nc_e_minus_l_normalized(d_correlator_outs[0], d_correlator_outs[2]); //[chips/Ti] //early and late
// Code discriminator filter
code_error_filt_chips = d_code_loop_filter.get_code_nco(code_error_chips_Ti); //input [chips/Ti] -> output [chips/second]
code_error_filt_secs_Ti = code_error_filt_chips*CURRENT_INTEGRATION_TIME_S/d_code_freq_chips; // [s/Ti]
// DLL code error estimation [s/Ti]
// TODO: PLL carrier aid to DLL is disabled. Re-enable it and measure performance
dll_code_error_secs_Ti = - code_error_filt_secs_Ti + d_pll_to_dll_assist_secs_Ti;
bool enable_dll_pll;
if (d_enable_20ms_integration==true)
{
long int symbol_diff=d_symbol_counter-d_preamble_index;
if (symbol_diff % GPS_CA_TELEMETRY_SYMBOLS_PER_BIT == 0)
{
// compute coherent integration and enable tracking loop
// perform coherent integration using correlator output history
//gr_complex d_correlator_outs_2[3];
//std::cout<<"##### RESET COHERENT INTEGRATION ####"<<std::endl;
d_correlator_outs[0]=gr_complex(0.0,0.0);
d_correlator_outs[1]=gr_complex(0.0,0.0);
d_correlator_outs[2]=gr_complex(0.0,0.0);
for (int n=0;n<GPS_CA_TELEMETRY_SYMBOLS_PER_BIT;n++)
{
d_correlator_outs[0]+=d_E_history.at(n);
d_correlator_outs[1]+=d_P_history.at(n);
d_correlator_outs[2]+=d_L_history.at(n);
}
// ################## CARRIER AND CODE NCO BUFFER ALIGNEMENT #######################
// keep alignment parameters for the next input buffer
double T_chip_seconds;
double T_prn_seconds;
double T_prn_samples;
double K_blk_samples;
// Compute the next buffer length based in the new period of the PRN sequence and the code phase error estimation
T_chip_seconds = 1 / d_code_freq_chips;
T_prn_seconds = T_chip_seconds * GPS_L1_CA_CODE_LENGTH_CHIPS;
T_prn_samples = T_prn_seconds * static_cast<double>(d_fs_in);
K_blk_samples = T_prn_samples + d_rem_code_phase_samples - dll_code_error_secs_Ti * static_cast<double>(d_fs_in);
if (d_preamble_synchronized==false)
{
d_preamble_synchronized=true;
}
current_synchro_data.symbol_integration_enabled=true;
// UPDATE INTEGRATION TIME
CURRENT_INTEGRATION_TIME_S = static_cast<double>(GPS_CA_TELEMETRY_SYMBOLS_PER_BIT)*GPS_L1_CA_CODE_PERIOD;
d_code_loop_filter.set_DLL_BW(d_dll_bw_hz);
d_carrier_loop_filter.set_params(10.0, d_pll_bw_hz/5,2);
enable_dll_pll=true;
d_correlation_length_samples = round(K_blk_samples); //round to a discrete samples
old_d_rem_code_phase_samples=d_rem_code_phase_samples;
d_rem_code_phase_samples = K_blk_samples - static_cast<double>(d_correlation_length_samples); //rounding error < 1 sample
}else{
current_synchro_data.symbol_integration_enabled=false;
if(d_preamble_synchronized==true)
{
// continue extended coherent correlation
d_correlation_length_samples=d_correlation_length_samples-d_rem_code_phase_integer_samples;
d_rem_code_phase_integer_samples=0;
d_rem_carrier_phase_rad = fmod(d_rem_carrier_phase_rad + d_carrier_phase_step_rad * d_correlation_length_samples, GPS_TWO_PI);
d_rem_code_phase_chips = fmod(d_rem_code_phase_chips + d_code_phase_step_chips*d_correlation_length_samples,GPS_L1_CA_CODE_LENGTH_CHIPS);
// disable tracking loop and inform telemetry decoder
enable_dll_pll=false;
}else{
// perform basic (1ms) correlation
// UPDATE INTEGRATION TIME
CURRENT_INTEGRATION_TIME_S = static_cast<double>(d_correlation_length_samples) / static_cast<double>(d_fs_in);
enable_dll_pll=true;
}
}
}else{
current_synchro_data.symbol_integration_enabled=false;
// UPDATE INTEGRATION TIME
CURRENT_INTEGRATION_TIME_S = static_cast<double>(d_correlation_length_samples) / static_cast<double>(d_fs_in);
enable_dll_pll=true;
}
// UPDATE REMNANT CARRIER PHASE
CORRECTED_INTEGRATION_TIME_S=(static_cast<double>(d_correlation_length_samples)/static_cast<double>(d_fs_in));
//remnant carrier phase [rad]
d_rem_carrier_phase_rad = fmod(d_rem_carrier_phase_rad + GPS_TWO_PI * d_carrier_doppler_hz * CORRECTED_INTEGRATION_TIME_S, GPS_TWO_PI);
// UPDATE CARRIER PHASE ACCUULATOR
//carrier phase accumulator prior to update the PLL estimators (accumulated carrier in this loop depends on the old estimations!)
d_acc_carrier_phase_cycles -= d_carrier_doppler_hz * CORRECTED_INTEGRATION_TIME_S;
// ###### end 20ms correlation extension
//################### PLL COMMANDS #################################################
//carrier phase step (NCO phase increment per sample) [rads/sample]
d_carrier_phase_step_rad = GPS_TWO_PI * d_carrier_doppler_hz / static_cast<double>(d_fs_in);
if (enable_dll_pll==true)
{
// ################## PLL ##########################################################
// Update PLL discriminator [rads/Ti -> Secs/Ti]
carr_phase_error_secs_Ti = pll_cloop_two_quadrant_atan(d_correlator_outs[1]) / GPS_TWO_PI; //prompt output
// Carrier discriminator filter
// NOTICE: The carrier loop filter includes the Carrier Doppler accumulator, as described in Kaplan
//d_carrier_doppler_hz = d_acq_carrier_doppler_hz + carr_phase_error_filt_secs_ti/INTEGRATION_TIME;
// Input [s/Ti] -> output [Hz]
d_carrier_doppler_hz = d_carrier_loop_filter.get_carrier_error(0.0, carr_phase_error_secs_Ti, CURRENT_INTEGRATION_TIME_S);
// PLL to DLL assistance [Secs/Ti]
d_pll_to_dll_assist_secs_Ti = (d_carrier_doppler_hz * CURRENT_INTEGRATION_TIME_S) / GPS_L1_FREQ_HZ;
// code Doppler frequency update
d_code_freq_chips = GPS_L1_CA_CODE_RATE_HZ + ((d_carrier_doppler_hz * GPS_L1_CA_CODE_RATE_HZ) / GPS_L1_FREQ_HZ);
//################### DLL COMMANDS #################################################
//code phase step (Code resampler phase increment per sample) [chips/sample]
d_code_phase_step_chips = d_code_freq_chips / static_cast<double>(d_fs_in);
//remnant code phase [chips]
d_rem_code_phase_chips = d_rem_code_phase_samples * (d_code_freq_chips / static_cast<double>(d_fs_in));
// ################## DLL ##########################################################
// DLL discriminator
code_error_chips_Ti = dll_nc_e_minus_l_normalized(d_correlator_outs[0], d_correlator_outs[2]); //[chips/Ti] //early and late
// Code discriminator filter
code_error_filt_chips = d_code_loop_filter.get_code_nco(code_error_chips_Ti); //input [chips/Ti] -> output [chips/second]
code_error_filt_secs_Ti = code_error_filt_chips*CURRENT_INTEGRATION_TIME_S/d_code_freq_chips; // [s/Ti]
// DLL code error estimation [s/Ti]
dll_code_error_secs_Ti = - code_error_filt_secs_Ti + d_pll_to_dll_assist_secs_Ti;
// ####### CN0 ESTIMATION AND LOCK DETECTORS #######################################
if (d_cn0_estimation_counter < CN0_ESTIMATION_SAMPLES)
{
// fill buffer with prompt correlator output values
d_Prompt_buffer[d_cn0_estimation_counter] = d_correlator_outs[1]; //prompt
d_cn0_estimation_counter++;
}
else
{
d_cn0_estimation_counter = 0;
// Code lock indicator
d_CN0_SNV_dB_Hz = cn0_svn_estimator(d_Prompt_buffer, CN0_ESTIMATION_SAMPLES, d_fs_in, GPS_L1_CA_CODE_LENGTH_CHIPS);
// Carrier lock indicator
d_carrier_lock_test = carrier_lock_detector(d_Prompt_buffer, CN0_ESTIMATION_SAMPLES);
// Loss of lock detection
if (d_carrier_lock_test < d_carrier_lock_threshold or d_CN0_SNV_dB_Hz < MINIMUM_VALID_CN0)
{
d_carrier_lock_fail_counter++;
}
else
{
if (d_carrier_lock_fail_counter > 0) d_carrier_lock_fail_counter--;
}
if (d_carrier_lock_fail_counter > MAXIMUM_LOCK_FAIL_COUNTER)
{
std::cout << "Loss of lock in channel " << d_channel << "!" << std::endl;
LOG(INFO) << "Loss of lock in channel " << d_channel << "!";
std::unique_ptr<ControlMessageFactory> cmf(new ControlMessageFactory());
if (d_queue != gr::msg_queue::sptr())
{
d_queue->handle(cmf->GetQueueMessage(d_channel, 2));
}
d_carrier_lock_fail_counter = 0;
d_enable_tracking = false; // TODO: check if disabling tracking is consistent with the channel state machine
}
}
// ################## CARRIER AND CODE NCO BUFFER ALIGNEMENT #######################
// ########### Output the tracking data to navigation and PVT ##########
current_synchro_data.Prompt_I = static_cast<double>((d_correlator_outs[1]).real());
current_synchro_data.Prompt_Q = static_cast<double>((d_correlator_outs[1]).imag());
// Tracking_timestamp_secs is aligned with the CURRENT PRN start sample (Hybridization OK!)
current_synchro_data.Tracking_timestamp_secs = (static_cast<double>(d_sample_counter) + old_d_rem_code_phase_samples) / static_cast<double>(d_fs_in);
// This tracking block aligns the Tracking_timestamp_secs with the start sample of the PRN, thus, Code_phase_secs=0
current_synchro_data.Code_phase_secs = 0;
current_synchro_data.Carrier_phase_rads = GPS_TWO_PI * d_acc_carrier_phase_cycles;
current_synchro_data.Carrier_Doppler_hz = d_carrier_doppler_hz;
current_synchro_data.CN0_dB_hz = d_CN0_SNV_dB_Hz;
current_synchro_data.Flag_valid_pseudorange = false;
*out[0] = current_synchro_data;
// keep alignment parameters for the next input buffer
double T_chip_seconds;
double T_prn_seconds;
double T_prn_samples;
double K_prn_samples;
// Compute the next buffer length based in the new period of the PRN sequence and the code phase error estimation
T_chip_seconds = 1 / d_code_freq_chips;
T_prn_seconds = T_chip_seconds * GPS_L1_CA_CODE_LENGTH_CHIPS;
T_prn_samples = T_prn_seconds * static_cast<double>(d_fs_in);
K_prn_samples = round(T_prn_samples);
double K_T_prn_error_samples=K_prn_samples-T_prn_samples;
old_d_rem_code_phase_samples=d_rem_code_phase_samples;
d_rem_code_phase_samples= d_rem_code_phase_samples - K_T_prn_error_samples -dll_code_error_secs_Ti * static_cast<double>(d_fs_in);
d_rem_code_phase_integer_samples=round(d_rem_code_phase_samples);
d_correlation_length_samples = K_prn_samples + d_rem_code_phase_integer_samples; //round to a discrete samples
d_rem_code_phase_samples=d_rem_code_phase_samples-d_rem_code_phase_integer_samples;
// UPDATE REMNANT CARRIER PHASE
CORRECTED_INTEGRATION_TIME_S=(static_cast<double>(d_correlation_length_samples)/static_cast<double>(d_fs_in));
//remnant carrier phase [rad]
d_rem_carrier_phase_rad = fmod(d_rem_carrier_phase_rad + GPS_TWO_PI * d_carrier_doppler_hz * CORRECTED_INTEGRATION_TIME_S, GPS_TWO_PI);
// UPDATE CARRIER PHASE ACCUULATOR
//carrier phase accumulator prior to update the PLL estimators (accumulated carrier in this loop depends on the old estimations!)
d_acc_carrier_phase_cycles -= d_carrier_doppler_hz * CORRECTED_INTEGRATION_TIME_S;
//################### PLL COMMANDS #################################################
//carrier phase step (NCO phase increment per sample) [rads/sample]
d_carrier_phase_step_rad = GPS_TWO_PI * d_carrier_doppler_hz / static_cast<double>(d_fs_in);
//################### DLL COMMANDS #################################################
//code phase step (Code resampler phase increment per sample) [chips/sample]
d_code_phase_step_chips = d_code_freq_chips / static_cast<double>(d_fs_in);
//remnant code phase [chips]
d_rem_code_phase_chips = d_rem_code_phase_samples * (d_code_freq_chips / static_cast<double>(d_fs_in));
// ####### CN0 ESTIMATION AND LOCK DETECTORS #######################################
if (d_cn0_estimation_counter < CN0_ESTIMATION_SAMPLES)
{
// fill buffer with prompt correlator output values
d_Prompt_buffer[d_cn0_estimation_counter] = d_correlator_outs[1]; //prompt
d_cn0_estimation_counter++;
}
else
{
d_cn0_estimation_counter = 0;
// Code lock indicator
d_CN0_SNV_dB_Hz = cn0_svn_estimator(d_Prompt_buffer, CN0_ESTIMATION_SAMPLES, d_fs_in, GPS_L1_CA_CODE_LENGTH_CHIPS);
// Carrier lock indicator
d_carrier_lock_test = carrier_lock_detector(d_Prompt_buffer, CN0_ESTIMATION_SAMPLES);
// Loss of lock detection
if (d_carrier_lock_test < d_carrier_lock_threshold or d_CN0_SNV_dB_Hz < MINIMUM_VALID_CN0)
{
d_carrier_lock_fail_counter++;
}
else
{
if (d_carrier_lock_fail_counter > 0) d_carrier_lock_fail_counter--;
}
if (d_carrier_lock_fail_counter > MAXIMUM_LOCK_FAIL_COUNTER)
{
std::cout << "Loss of lock in channel " << d_channel << "!" << std::endl;
LOG(INFO) << "Loss of lock in channel " << d_channel << "!";
std::unique_ptr<ControlMessageFactory> cmf(new ControlMessageFactory());
if (d_queue != gr::msg_queue::sptr())
{
d_queue->handle(cmf->GetQueueMessage(d_channel, 2));
}
d_carrier_lock_fail_counter = 0;
d_enable_tracking = false; // TODO: check if disabling tracking is consistent with the channel state machine
}
}
// ########### Output the tracking data to navigation and PVT ##########
current_synchro_data.Prompt_I = static_cast<double>((d_correlator_outs[1]).real());
current_synchro_data.Prompt_Q = static_cast<double>((d_correlator_outs[1]).imag());
// Tracking_timestamp_secs is aligned with the CURRENT PRN start sample (Hybridization OK!)
current_synchro_data.Tracking_timestamp_secs = (static_cast<double>(d_sample_counter) + old_d_rem_code_phase_samples) / static_cast<double>(d_fs_in);
// This tracking block aligns the Tracking_timestamp_secs with the start sample of the PRN, thus, Code_phase_secs=0
current_synchro_data.Code_phase_secs = 0;
current_synchro_data.Carrier_phase_rads = GPS_TWO_PI * d_acc_carrier_phase_cycles;
current_synchro_data.Carrier_Doppler_hz = d_carrier_doppler_hz;
current_synchro_data.CN0_dB_hz = d_CN0_SNV_dB_Hz;
current_synchro_data.Flag_valid_pseudorange = false;
current_synchro_data.Flag_valid_symbol_output = true;
*out[0] = current_synchro_data;
}else{
//todo: fill synchronization data to produce output while coherent integration is running
current_synchro_data.Flag_valid_symbol_output = false;
current_synchro_data.Prompt_I = static_cast<double>((d_correlator_outs[1]).real());
current_synchro_data.Prompt_Q = static_cast<double>((d_correlator_outs[1]).imag());
// Tracking_timestamp_secs is aligned with the CURRENT PRN start sample (Hybridization OK!)
current_synchro_data.Tracking_timestamp_secs = (static_cast<double>(d_sample_counter) + d_rem_code_phase_samples) / static_cast<double>(d_fs_in);
// This tracking block aligns the Tracking_timestamp_secs with the start sample of the PRN, thus, Code_phase_secs=0
current_synchro_data.Code_phase_secs = 0;
current_synchro_data.Carrier_phase_rads = GPS_TWO_PI * d_acc_carrier_phase_cycles; // todo: project the acc carrier phase
current_synchro_data.Carrier_Doppler_hz = d_carrier_doppler_hz;// todo: project the carrier doppler
current_synchro_data.CN0_dB_hz = d_CN0_SNV_dB_Hz;
current_synchro_data.Flag_valid_pseudorange = false;
*out[0] = current_synchro_data;
}
// ########## DEBUG OUTPUT
/*!
@@ -553,6 +669,7 @@ int gps_l1_ca_dll_pll_c_aid_tracking_cc::general_work (int noutput_items, gr_vec
{
LOG(WARNING) << "noutput_items = 0";
}
d_symbol_counter++;
return 1; //output tracking result ALWAYS even in the case of d_enable_tracking==false
}

16
src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_pll_c_aid_tracking_cc.h
View File

@@ -39,9 +39,11 @@
#include <fstream>
#include <map>
#include <deque>
#include <string>
#include <gnuradio/block.h>
#include <gnuradio/msg_queue.h>
#include <pmt/pmt.h>
#include "concurrent_queue.h"
#include "gnss_synchro.h"
#include "tracking_2nd_DLL_filter.h"
@@ -130,6 +132,7 @@ private:
double d_rem_code_phase_samples;
double d_rem_code_phase_chips;
double d_rem_carrier_phase_rad;
int d_rem_code_phase_integer_samples;
// PLL and DLL filter library
Tracking_2nd_DLL_filter d_code_loop_filter;
@@ -140,6 +143,8 @@ private:
double d_acq_carrier_doppler_hz;
// tracking vars
float d_dll_bw_hz;
float d_pll_bw_hz;
double d_code_freq_chips;
double d_code_phase_step_chips;
double d_carrier_doppler_hz;
@@ -148,6 +153,17 @@ private:
double d_code_phase_samples;
double d_pll_to_dll_assist_secs_Ti;
// symbol history to detect bit transition
std::deque<gr_complex> d_E_history;
std::deque<gr_complex> d_P_history;
std::deque<gr_complex> d_L_history;
long int d_preamble_index;
long int d_symbol_counter;
bool d_enable_20ms_integration;
bool d_preamble_synchronized;
int d_correlation_symbol_counter;
void msg_handler_preamble_index(pmt::pmt_t msg);
//Integration period in samples
int d_correlation_length_samples;