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mirror of https://github.com/gnss-sdr/gnss-sdr synced 2024-11-10 12:00:04 +00:00

Improving tracking stability of carrier lock detector

This commit is contained in:
Javier Arribas 2019-06-11 20:20:23 +02:00
parent d89710e375
commit 559080b651
16 changed files with 151 additions and 219 deletions

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@ -65,9 +65,12 @@ DEFINE_int32(cn0_samples, 20, "Number of correlator outputs used for CN0 estimat
DEFINE_int32(cn0_min, 25, "Minimum valid CN0 (in dB-Hz).");
DEFINE_int32(max_lock_fail, 50, "Maximum number of lock failures before dropping a satellite.");
DEFINE_int32(max_carrier_lock_fail, 5000, "Maximum number of carrier lock failures before dropping a satellite.");
DEFINE_double(carrier_lock_th, 0.85, "Carrier lock threshold (in rad).");
DEFINE_int32(max_lock_fail, 50, "Maximum number of code lock failures before dropping a satellite.");
//cos(2xError_angle)=0.7 -> Error_angle=22 deg
DEFINE_double(carrier_lock_th, 0.7, "Carrier lock threshold (in rad).");
DEFINE_string(RINEX_version, "-", "If defined, specifies the RINEX version (2.11 or 3.02). Overrides the configuration file.");

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@ -50,7 +50,8 @@ DECLARE_int32(doppler_step); //!< If defined, sets the frequency step in the se
// Declare flags for tracking blocks
DECLARE_int32(cn0_samples); //!< Number of correlator outputs used for CN0 estimation.
DECLARE_int32(cn0_min); //!< Minimum valid CN0 (in dB-Hz).
DECLARE_int32(max_lock_fail); //!< Maximum number of lock failures before dropping a satellite.
DECLARE_int32(max_lock_fail); //!< Maximum number of code lock failures before dropping a satellite.
DECLARE_int32(max_carrier_lock_fail); //!< Maximum number of carrier lock failures before dropping a satellite.
DECLARE_double(carrier_lock_th); //!< Carrier lock threshold (in rad).
DECLARE_double(dll_bw_hz); //!< Bandwidth of the DLL low pass filter, in Hz (overrides the configuration file).
DECLARE_double(pll_bw_hz); //!< Bandwidth of the PLL low pass filter, in Hz (overrides the configuration file).

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@ -430,7 +430,14 @@ int gps_l1_ca_telemetry_decoder_gs::general_work(int noutput_items __attribute__
{
DLOG(INFO) << "Preamble confirmation for SAT " << this->d_satellite;
d_preamble_index = d_sample_counter; // record the preamble sample stamp
if (corr_value < 0) flag_PLL_180_deg_phase_locked = true;
if (corr_value < 0)
{
flag_PLL_180_deg_phase_locked = true;
}
else
{
flag_PLL_180_deg_phase_locked = false;
}
d_stat = 2;
}
else

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@ -64,7 +64,7 @@ gps_l5_telemetry_decoder_gs::gps_l5_telemetry_decoder_gs(
this->message_port_register_out(pmt::mp("telemetry_to_trk"));
d_last_valid_preamble = 0;
d_sent_tlm_failed_msg = false;
d_max_symbols_without_valid_frame = GPS_L5_CNAV_DATA_PAGE_BITS * GPS_L5_SAMPLES_PER_SYMBOL * GPS_L5_SYMBOLS_PER_BIT * 5; //rise alarm if 5 consecutive subframes have no valid CRC
d_max_symbols_without_valid_frame = GPS_L5_CNAV_DATA_PAGE_BITS * GPS_L5_SAMPLES_PER_SYMBOL * GPS_L5_SYMBOLS_PER_BIT * 10; //rise alarm if 10 consecutive subframes have no valid CRC
// initialize internal vars
d_dump = dump;

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@ -152,30 +152,12 @@ BeidouB1iDllPllTracking::BeidouB1iDllPllTracking(
trk_param.system = 'C';
char sig_[3] = "B1";
std::memcpy(trk_param.signal, sig_, 3);
int cn0_samples = configuration->property(role + ".cn0_samples", 20);
if (FLAGS_cn0_samples != 20)
{
cn0_samples = FLAGS_cn0_samples;
}
trk_param.cn0_samples = cn0_samples;
int cn0_min = configuration->property(role + ".cn0_min", 25);
if (FLAGS_cn0_min != 25)
{
cn0_min = FLAGS_cn0_min;
}
trk_param.cn0_min = cn0_min;
int max_lock_fail = configuration->property(role + ".max_lock_fail", 50);
if (FLAGS_max_lock_fail != 50)
{
max_lock_fail = FLAGS_max_lock_fail;
}
trk_param.max_lock_fail = max_lock_fail;
double carrier_lock_th = configuration->property(role + ".carrier_lock_th", 0.85);
if (FLAGS_carrier_lock_th != 0.85)
{
carrier_lock_th = FLAGS_carrier_lock_th;
}
trk_param.carrier_lock_th = carrier_lock_th;
trk_param.cn0_samples = configuration->property(role + ".cn0_samples", trk_param.cn0_samples);
trk_param.cn0_min = configuration->property(role + ".cn0_min", trk_param.cn0_min);
trk_param.max_code_lock_fail = configuration->property(role + ".max_lock_fail", trk_param.max_code_lock_fail);
trk_param.max_carrier_lock_fail = configuration->property(role + ".max_carrier_lock_fail", trk_param.max_carrier_lock_fail);
trk_param.carrier_lock_th = configuration->property(role + ".carrier_lock_th", trk_param.carrier_lock_th);
//################# MAKE TRACKING GNURadio object ###################
if (item_type == "gr_complex")

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@ -147,18 +147,11 @@ BeidouB3iDllPllTracking::BeidouB3iDllPllTracking(
trk_param.system = 'C';
char sig_[3] = "B3";
std::memcpy(trk_param.signal, sig_, 3);
int cn0_samples = configuration->property(role + ".cn0_samples", 20);
if (FLAGS_cn0_samples != 20) cn0_samples = FLAGS_cn0_samples;
trk_param.cn0_samples = cn0_samples;
int cn0_min = configuration->property(role + ".cn0_min", 25);
if (FLAGS_cn0_min != 25) cn0_min = FLAGS_cn0_min;
trk_param.cn0_min = cn0_min;
int max_lock_fail = configuration->property(role + ".max_lock_fail", 50);
if (FLAGS_max_lock_fail != 50) max_lock_fail = FLAGS_max_lock_fail;
trk_param.max_lock_fail = max_lock_fail;
double carrier_lock_th = configuration->property(role + ".carrier_lock_th", 0.85);
if (FLAGS_carrier_lock_th != 0.85) carrier_lock_th = FLAGS_carrier_lock_th;
trk_param.carrier_lock_th = carrier_lock_th;
trk_param.cn0_samples = configuration->property(role + ".cn0_samples", trk_param.cn0_samples);
trk_param.cn0_min = configuration->property(role + ".cn0_min", trk_param.cn0_min);
trk_param.max_code_lock_fail = configuration->property(role + ".max_lock_fail", trk_param.max_code_lock_fail);
trk_param.max_carrier_lock_fail = configuration->property(role + ".max_carrier_lock_fail", trk_param.max_carrier_lock_fail);
trk_param.carrier_lock_th = configuration->property(role + ".carrier_lock_th", trk_param.carrier_lock_th);
//################# MAKE TRACKING GNURadio object ###################
if (item_type == "gr_complex")

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@ -162,30 +162,11 @@ GalileoE1DllPllVemlTracking::GalileoE1DllPllVemlTracking(
trk_param.system = 'E';
char sig_[3] = "1B";
std::memcpy(trk_param.signal, sig_, 3);
int cn0_samples = configuration->property(role + ".cn0_samples", 20);
if (FLAGS_cn0_samples != 20)
{
cn0_samples = FLAGS_cn0_samples;
}
trk_param.cn0_samples = cn0_samples;
int cn0_min = configuration->property(role + ".cn0_min", 25);
if (FLAGS_cn0_min != 25)
{
cn0_min = FLAGS_cn0_min;
}
trk_param.cn0_min = cn0_min;
int max_lock_fail = configuration->property(role + ".max_lock_fail", 50);
if (FLAGS_max_lock_fail != 50)
{
max_lock_fail = FLAGS_max_lock_fail;
}
trk_param.max_lock_fail = max_lock_fail;
double carrier_lock_th = configuration->property(role + ".carrier_lock_th", 0.85);
if (FLAGS_carrier_lock_th != 0.85)
{
carrier_lock_th = FLAGS_carrier_lock_th;
}
trk_param.carrier_lock_th = carrier_lock_th;
trk_param.cn0_samples = configuration->property(role + ".cn0_samples", trk_param.cn0_samples);
trk_param.cn0_min = configuration->property(role + ".cn0_min", trk_param.cn0_min);
trk_param.max_code_lock_fail = configuration->property(role + ".max_lock_fail", trk_param.max_code_lock_fail);
trk_param.max_carrier_lock_fail = configuration->property(role + ".max_carrier_lock_fail", trk_param.max_carrier_lock_fail);
trk_param.carrier_lock_th = configuration->property(role + ".carrier_lock_th", trk_param.carrier_lock_th);
//################# MAKE TRACKING GNURadio object ###################
if (item_type == "gr_complex")

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@ -159,30 +159,11 @@ GalileoE5aDllPllTracking::GalileoE5aDllPllTracking(
trk_param.system = 'E';
char sig_[3] = "5X";
std::memcpy(trk_param.signal, sig_, 3);
int cn0_samples = configuration->property(role + ".cn0_samples", 20);
if (FLAGS_cn0_samples != 20)
{
cn0_samples = FLAGS_cn0_samples;
}
trk_param.cn0_samples = cn0_samples;
int cn0_min = configuration->property(role + ".cn0_min", 25);
if (FLAGS_cn0_min != 25)
{
cn0_min = FLAGS_cn0_min;
}
trk_param.cn0_min = cn0_min;
int max_lock_fail = configuration->property(role + ".max_lock_fail", 50);
if (FLAGS_max_lock_fail != 50)
{
max_lock_fail = FLAGS_max_lock_fail;
}
trk_param.max_lock_fail = max_lock_fail;
double carrier_lock_th = configuration->property(role + ".carrier_lock_th", 0.85);
if (FLAGS_carrier_lock_th != 0.85)
{
carrier_lock_th = FLAGS_carrier_lock_th;
}
trk_param.carrier_lock_th = carrier_lock_th;
trk_param.cn0_samples = configuration->property(role + ".cn0_samples", trk_param.cn0_samples);
trk_param.cn0_min = configuration->property(role + ".cn0_min", trk_param.cn0_min);
trk_param.max_code_lock_fail = configuration->property(role + ".max_lock_fail", trk_param.max_code_lock_fail);
trk_param.max_carrier_lock_fail = configuration->property(role + ".max_carrier_lock_fail", trk_param.max_carrier_lock_fail);
trk_param.carrier_lock_th = configuration->property(role + ".carrier_lock_th", trk_param.carrier_lock_th);
//################# MAKE TRACKING GNURadio object ###################
if (item_type == "gr_complex")

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@ -165,30 +165,11 @@ GpsL1CaDllPllTracking::GpsL1CaDllPllTracking(
trk_param.system = 'G';
char sig_[3] = "1C";
std::memcpy(trk_param.signal, sig_, 3);
int cn0_samples = configuration->property(role + ".cn0_samples", 20);
if (FLAGS_cn0_samples != 20)
{
cn0_samples = FLAGS_cn0_samples;
}
trk_param.cn0_samples = cn0_samples;
int cn0_min = configuration->property(role + ".cn0_min", 30);
if (FLAGS_cn0_min != 25)
{
cn0_min = FLAGS_cn0_min;
}
trk_param.cn0_min = cn0_min;
int max_lock_fail = configuration->property(role + ".max_lock_fail", 50);
if (FLAGS_max_lock_fail != 50)
{
max_lock_fail = FLAGS_max_lock_fail;
}
trk_param.max_lock_fail = max_lock_fail;
double carrier_lock_th = configuration->property(role + ".carrier_lock_th", 0.80);
if (FLAGS_carrier_lock_th != 0.85)
{
carrier_lock_th = FLAGS_carrier_lock_th;
}
trk_param.carrier_lock_th = carrier_lock_th;
trk_param.cn0_samples = configuration->property(role + ".cn0_samples", trk_param.cn0_samples);
trk_param.cn0_min = configuration->property(role + ".cn0_min", trk_param.cn0_min);
trk_param.max_code_lock_fail = configuration->property(role + ".max_lock_fail", trk_param.max_code_lock_fail);
trk_param.max_carrier_lock_fail = configuration->property(role + ".max_carrier_lock_fail", trk_param.max_carrier_lock_fail);
trk_param.carrier_lock_th = configuration->property(role + ".carrier_lock_th", trk_param.carrier_lock_th);
//################# MAKE TRACKING GNURadio object ###################
if (item_type == "gr_complex")

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@ -141,30 +141,11 @@ GpsL2MDllPllTracking::GpsL2MDllPllTracking(
trk_param.system = 'G';
char sig_[3] = "2S";
std::memcpy(trk_param.signal, sig_, 3);
int cn0_samples = configuration->property(role + ".cn0_samples", 20);
if (FLAGS_cn0_samples != 20)
{
cn0_samples = FLAGS_cn0_samples;
}
trk_param.cn0_samples = cn0_samples;
int cn0_min = configuration->property(role + ".cn0_min", 25);
if (FLAGS_cn0_min != 25)
{
cn0_min = FLAGS_cn0_min;
}
trk_param.cn0_min = cn0_min;
int max_lock_fail = configuration->property(role + ".max_lock_fail", 50);
if (FLAGS_max_lock_fail != 50)
{
max_lock_fail = FLAGS_max_lock_fail;
}
trk_param.max_lock_fail = max_lock_fail;
double carrier_lock_th = configuration->property(role + ".carrier_lock_th", 0.85);
if (FLAGS_carrier_lock_th != 0.85)
{
carrier_lock_th = FLAGS_carrier_lock_th;
}
trk_param.carrier_lock_th = carrier_lock_th;
trk_param.cn0_samples = configuration->property(role + ".cn0_samples", trk_param.cn0_samples);
trk_param.cn0_min = configuration->property(role + ".cn0_min", trk_param.cn0_min);
trk_param.max_code_lock_fail = configuration->property(role + ".max_lock_fail", trk_param.max_code_lock_fail);
trk_param.max_carrier_lock_fail = configuration->property(role + ".max_carrier_lock_fail", trk_param.max_carrier_lock_fail);
trk_param.carrier_lock_th = configuration->property(role + ".carrier_lock_th", trk_param.carrier_lock_th);
//################# MAKE TRACKING GNURadio object ###################
if (item_type == "gr_complex")

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@ -160,30 +160,12 @@ GpsL5DllPllTracking::GpsL5DllPllTracking(
trk_param.system = 'G';
char sig_[3] = "L5";
std::memcpy(trk_param.signal, sig_, 3);
int cn0_samples = configuration->property(role + ".cn0_samples", 20);
if (FLAGS_cn0_samples != 20)
{
cn0_samples = FLAGS_cn0_samples;
}
trk_param.cn0_samples = cn0_samples;
int cn0_min = configuration->property(role + ".cn0_min", 25);
if (FLAGS_cn0_min != 25)
{
cn0_min = FLAGS_cn0_min;
}
trk_param.cn0_min = cn0_min;
int max_lock_fail = configuration->property(role + ".max_lock_fail", 50);
if (FLAGS_max_lock_fail != 50)
{
max_lock_fail = FLAGS_max_lock_fail;
}
trk_param.max_lock_fail = max_lock_fail;
double carrier_lock_th = configuration->property(role + ".carrier_lock_th", 0.75);
if (FLAGS_carrier_lock_th != 0.85)
{
carrier_lock_th = FLAGS_carrier_lock_th;
}
trk_param.carrier_lock_th = carrier_lock_th;
trk_param.cn0_samples = configuration->property(role + ".cn0_samples", trk_param.cn0_samples);
trk_param.cn0_min = configuration->property(role + ".cn0_min", trk_param.cn0_min);
trk_param.max_code_lock_fail = configuration->property(role + ".max_lock_fail", trk_param.max_code_lock_fail);
trk_param.max_carrier_lock_fail = configuration->property(role + ".max_carrier_lock_fail", trk_param.max_carrier_lock_fail);
trk_param.carrier_lock_th = configuration->property(role + ".carrier_lock_th", trk_param.carrier_lock_th);
//################# MAKE TRACKING GNURadio object ###################
if (item_type == "gr_complex")

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@ -444,6 +444,7 @@ dll_pll_veml_tracking::dll_pll_veml_tracking(const Dll_Pll_Conf &conf_) : gr::bl
d_carrier_lock_test = 1.0;
d_CN0_SNV_dB_Hz = 0.0;
d_carrier_lock_fail_counter = 0;
d_code_lock_fail_counter = 0;
d_carrier_lock_threshold = trk_parameters.carrier_lock_th;
d_Prompt_Data = static_cast<gr_complex *>(volk_gnsssdr_malloc(sizeof(gr_complex), volk_gnsssdr_get_alignment()));
d_cn0_smoother = Exponential_Smoother();
@ -451,6 +452,13 @@ dll_pll_veml_tracking::dll_pll_veml_tracking(const Dll_Pll_Conf &conf_) : gr::bl
{
d_cn0_smoother.set_samples_for_initialization(200 / static_cast<int>(d_code_period * 1000.0));
}
d_carrier_lock_test_smoother = Exponential_Smoother();
d_carrier_lock_test_smoother.set_alpha(0.002);
d_carrier_lock_test_smoother.set_min_value(-1.0);
d_carrier_lock_test_smoother.set_offset(0.0);
d_carrier_lock_test_smoother.set_samples_for_initialization(25);
d_acquisition_gnss_synchro = nullptr;
d_channel = 0;
d_acq_code_phase_samples = 0.0;
@ -717,6 +725,7 @@ void dll_pll_veml_tracking::start_tracking()
std::fill_n(d_correlator_outs, d_n_correlator_taps, gr_complex(0.0, 0.0));
d_carrier_lock_fail_counter = 0;
d_code_lock_fail_counter = 0;
d_rem_code_phase_samples = 0.0;
d_rem_carr_phase_rad = 0.0;
d_rem_code_phase_chips = 0.0;
@ -866,11 +875,13 @@ bool dll_pll_veml_tracking::cn0_and_tracking_lock_status(double coh_integration_
float d_CN0_SNV_dB_Hz_raw = cn0_svn_estimator(d_Prompt_buffer, trk_parameters.cn0_samples, static_cast<float>(coh_integration_time_s));
d_CN0_SNV_dB_Hz = d_cn0_smoother.smooth(d_CN0_SNV_dB_Hz_raw);
// Carrier lock indicator
d_carrier_lock_test = carrier_lock_detector(d_Prompt_buffer, trk_parameters.cn0_samples);
d_carrier_lock_test = d_carrier_lock_test_smoother.smooth(carrier_lock_detector(d_Prompt_buffer, 1));
//d_carrier_lock_test = carrier_lock_detector(d_Prompt_buffer, trk_parameters.cn0_samples);
// Loss of lock detection
if (!d_pull_in_transitory)
{
if (d_carrier_lock_test < d_carrier_lock_threshold or d_CN0_SNV_dB_Hz < trk_parameters.cn0_min)
//d_carrier_lock_test < d_carrier_lock_threshold or
if (d_carrier_lock_test < d_carrier_lock_threshold)
{
d_carrier_lock_fail_counter++;
}
@ -881,13 +892,28 @@ bool dll_pll_veml_tracking::cn0_and_tracking_lock_status(double coh_integration_
d_carrier_lock_fail_counter--;
}
}
if (d_CN0_SNV_dB_Hz < trk_parameters.cn0_min)
{
d_code_lock_fail_counter++;
}
if (d_carrier_lock_fail_counter > trk_parameters.max_lock_fail)
else
{
if (d_code_lock_fail_counter > 0)
{
d_code_lock_fail_counter--;
}
}
}
if (d_carrier_lock_fail_counter > trk_parameters.max_carrier_lock_fail or d_code_lock_fail_counter > trk_parameters.max_code_lock_fail)
{
std::cout << "Loss of lock in channel " << d_channel << "!" << std::endl;
LOG(INFO) << "Loss of lock in channel " << d_channel << "!";
LOG(INFO) << "Loss of lock in channel " << d_channel
<< " (carrier_lock_fail_counter:" << d_carrier_lock_fail_counter
<< " code_lock_fail_counter : " << d_code_lock_fail_counter << ")";
this->message_port_pub(pmt::mp("events"), pmt::from_long(3)); // 3 -> loss of lock
d_carrier_lock_fail_counter = 0;
d_code_lock_fail_counter = 0;
return false;
}
return true;
@ -1573,6 +1599,8 @@ int dll_pll_veml_tracking::general_work(int noutput_items __attribute__((unused)
if (trk_parameters.pull_in_time_s < (d_sample_counter - d_acq_sample_stamp) / static_cast<int>(trk_parameters.fs_in))
{
d_pull_in_transitory = false;
d_carrier_lock_fail_counter = 0;
d_code_lock_fail_counter = 0;
}
}
switch (d_state)
@ -1606,6 +1634,7 @@ int dll_pll_veml_tracking::general_work(int noutput_items __attribute__((unused)
d_state = 2;
d_sample_counter += samples_offset; // count for the processed samples
d_cn0_smoother.reset();
d_carrier_lock_test_smoother.reset();
DLOG(INFO) << "Number of samples between Acquisition and Tracking = " << acq_trk_diff_samples << " ( " << acq_trk_diff_seconds << " s)";
DLOG(INFO) << "PULL-IN Doppler [Hz] = " << d_carrier_doppler_hz
@ -1642,6 +1671,9 @@ int dll_pll_veml_tracking::general_work(int noutput_items __attribute__((unused)
// enable write dump file this cycle (valid DLL/PLL cycle)
log_data(false);
if (!d_pull_in_transitory)
{
if (d_secondary)
{
// ####### SECONDARY CODE LOCK #####
@ -1702,7 +1734,11 @@ int dll_pll_veml_tracking::general_work(int noutput_items __attribute__((unused)
{
next_state = true;
}
}
else
{
next_state = false; //keep in state 2 during pull-in transitory
}
// ########### Output the tracking results to Telemetry block ##########
if (interchange_iq)
{
@ -1837,7 +1873,6 @@ int dll_pll_veml_tracking::general_work(int noutput_items __attribute__((unused)
d_extend_correlation_symbols_count = 0;
d_state = 4;
}
log_data(true);
break;
}
case 4: // narrow tracking

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@ -193,13 +193,14 @@ private:
// CN0 estimation and lock detector
int32_t d_cn0_estimation_counter;
int32_t d_carrier_lock_fail_counter;
int32_t d_code_lock_fail_counter;
double d_carrier_lock_test;
double d_CN0_SNV_dB_Hz;
double d_carrier_lock_threshold;
boost::circular_buffer<gr_complex> d_Prompt_circular_buffer;
gr_complex *d_Prompt_buffer;
Exponential_Smoother d_cn0_smoother;
Exponential_Smoother d_carrier_lock_test_smoother;
// file dump
std::ofstream d_dump_file;
std::string d_dump_filename;

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@ -82,6 +82,7 @@ target_link_libraries(tracking_libs
Gnuradio::runtime
Volkgnsssdr::volkgnsssdr
core_system_parameters
algorithms_libs
${OPT_TRACKING_LIBRARIES}
PRIVATE
Gflags::gflags

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@ -31,6 +31,7 @@
#include "dll_pll_conf.h"
#include "gnss_sdr_flags.h"
#include <cstring>
Dll_Pll_Conf::Dll_Pll_Conf()
@ -61,11 +62,12 @@ Dll_Pll_Conf::Dll_Pll_Conf()
early_late_space_narrow_chips = 0.1;
very_early_late_space_narrow_chips = 0.1;
extend_correlation_symbols = 5;
cn0_samples = 20;
carrier_lock_det_mav_samples = 20;
cn0_min = 25;
max_lock_fail = 50;
carrier_lock_th = 0.85;
cn0_samples = FLAGS_cn0_samples;
carrier_lock_det_mav_samples = FLAGS_cn0_samples;
cn0_min = FLAGS_cn0_min;
max_carrier_lock_fail = FLAGS_max_carrier_lock_fail;
max_code_lock_fail = FLAGS_max_lock_fail;
carrier_lock_th = FLAGS_carrier_lock_th;
track_pilot = false;
system = 'G';
char sig_[3] = "1C";

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@ -69,7 +69,8 @@ public:
int32_t cn0_samples;
int32_t carrier_lock_det_mav_samples;
int32_t cn0_min;
int32_t max_lock_fail;
int32_t max_code_lock_fail;
int32_t max_carrier_lock_fail;
uint32_t smoother_length;
double carrier_lock_th;
bool track_pilot;