mirror of
https://github.com/gnss-sdr/gnss-sdr
synced 2024-12-14 12:10:34 +00:00
added the bit synchronization time limit and the doppler correction
This commit is contained in:
parent
fc18eba4dd
commit
3095176524
@ -58,6 +58,7 @@
|
|||||||
#include <exception>
|
#include <exception>
|
||||||
#include <iostream>
|
#include <iostream>
|
||||||
#include <map>
|
#include <map>
|
||||||
|
#include <numeric>
|
||||||
#include <vector>
|
#include <vector>
|
||||||
|
|
||||||
#if HAS_STD_FILESYSTEM
|
#if HAS_STD_FILESYSTEM
|
||||||
@ -96,6 +97,7 @@ dll_pll_veml_tracking_fpga::dll_pll_veml_tracking_fpga(const Dll_Pll_Conf_Fpga &
|
|||||||
this->set_msg_handler(pmt::mp("telemetry_to_trk"), boost::bind(&dll_pll_veml_tracking_fpga::msg_handler_telemetry_to_trk, this, _1));
|
this->set_msg_handler(pmt::mp("telemetry_to_trk"), boost::bind(&dll_pll_veml_tracking_fpga::msg_handler_telemetry_to_trk, this, _1));
|
||||||
|
|
||||||
// initialize internal vars
|
// initialize internal vars
|
||||||
|
d_dll_filt_history.set_capacity(2000);
|
||||||
d_veml = false;
|
d_veml = false;
|
||||||
d_cloop = true;
|
d_cloop = true;
|
||||||
d_pull_in_transitory = true;
|
d_pull_in_transitory = true;
|
||||||
@ -563,11 +565,15 @@ dll_pll_veml_tracking_fpga::dll_pll_veml_tracking_fpga(const Dll_Pll_Conf_Fpga &
|
|||||||
d_num_current_syncrho_repetitions = 1;
|
d_num_current_syncrho_repetitions = 1;
|
||||||
|
|
||||||
|
|
||||||
|
d_corrected_doppler = false;
|
||||||
|
|
||||||
// debug - erase previous outfile contents
|
// debug - erase previous outfile contents
|
||||||
std::ofstream outfile;
|
std::ofstream outfile;
|
||||||
outfile.open("trk_out.txt", std::ios_base::trunc);
|
outfile.open("trk_out.txt", std::ios_base::trunc);
|
||||||
outfile.close();
|
outfile.close();
|
||||||
d_worker_is_done = false;
|
d_worker_is_done = false;
|
||||||
|
|
||||||
|
|
||||||
}
|
}
|
||||||
|
|
||||||
void dll_pll_veml_tracking_fpga::msg_handler_telemetry_to_trk(const pmt::pmt_t &msg)
|
void dll_pll_veml_tracking_fpga::msg_handler_telemetry_to_trk(const pmt::pmt_t &msg)
|
||||||
@ -623,6 +629,8 @@ void dll_pll_veml_tracking_fpga::start_tracking()
|
|||||||
d_carrier_loop_filter.initialize(static_cast<float>(d_acq_carrier_doppler_hz)); // initialize the carrier filter
|
d_carrier_loop_filter.initialize(static_cast<float>(d_acq_carrier_doppler_hz)); // initialize the carrier filter
|
||||||
|
|
||||||
|
|
||||||
|
d_corrected_doppler = false;
|
||||||
|
|
||||||
boost::mutex::scoped_lock lock(d_mutex);
|
boost::mutex::scoped_lock lock(d_mutex);
|
||||||
d_worker_is_done = true;
|
d_worker_is_done = true;
|
||||||
m_condition.notify_one();
|
m_condition.notify_one();
|
||||||
@ -847,6 +855,29 @@ void dll_pll_veml_tracking_fpga::run_dll_pll()
|
|||||||
|
|
||||||
// New code Doppler frequency estimation
|
// New code Doppler frequency estimation
|
||||||
d_code_freq_chips = (1.0 + (d_carrier_doppler_hz / d_signal_carrier_freq)) * d_code_chip_rate - d_code_error_filt_chips;
|
d_code_freq_chips = (1.0 + (d_carrier_doppler_hz / d_signal_carrier_freq)) * d_code_chip_rate - d_code_error_filt_chips;
|
||||||
|
|
||||||
|
// Experimental: detect Carrier Doppler vs. Code Doppler incoherence and correct the Carrier Doppler
|
||||||
|
if (trk_parameters.enable_doppler_correction == true)
|
||||||
|
{
|
||||||
|
if (d_pull_in_transitory == false and d_corrected_doppler == false)
|
||||||
|
{
|
||||||
|
d_dll_filt_history.push_back(static_cast<float>(d_code_error_filt_chips));
|
||||||
|
|
||||||
|
if (d_dll_filt_history.full())
|
||||||
|
{
|
||||||
|
float avg_code_error_chips_s = std::accumulate(d_dll_filt_history.begin(), d_dll_filt_history.end(), 0.0) / static_cast<float>(d_dll_filt_history.capacity());
|
||||||
|
if (fabs(avg_code_error_chips_s) > 1.0)
|
||||||
|
{
|
||||||
|
float carrier_doppler_error_hz = static_cast<float>(d_signal_carrier_freq) * avg_code_error_chips_s / static_cast<float>(d_code_chip_rate);
|
||||||
|
LOG(INFO) << "Detected and corrected carrier doppler error: " << carrier_doppler_error_hz << " [Hz] on sat " << Gnss_Satellite(systemName, d_acquisition_gnss_synchro->PRN);
|
||||||
|
d_carrier_loop_filter.initialize(d_carrier_doppler_hz - carrier_doppler_error_hz);
|
||||||
|
d_corrected_doppler = true;
|
||||||
|
}
|
||||||
|
d_dll_filt_history.clear();
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
}
|
}
|
||||||
|
|
||||||
|
|
||||||
@ -1974,6 +2005,14 @@ int dll_pll_veml_tracking_fpga::general_work(int noutput_items __attribute__((un
|
|||||||
d_P_accu = *d_Prompt;
|
d_P_accu = *d_Prompt;
|
||||||
d_L_accu = *d_Late;
|
d_L_accu = *d_Late;
|
||||||
|
|
||||||
|
//fail-safe: check if the secondary code or bit synchronization has not succedded in a limited time period
|
||||||
|
if (trk_parameters.bit_synchronization_time_limit_s < (d_sample_counter - d_acq_sample_stamp) / static_cast<int>(trk_parameters.fs_in))
|
||||||
|
{
|
||||||
|
d_carrier_lock_fail_counter = 300000; //force loss-of-lock condition
|
||||||
|
LOG(INFO) << systemName << " " << signal_pretty_name << " tracking synchronization time limit reached in channel " << d_channel
|
||||||
|
<< " for satellite " << Gnss_Satellite(systemName, d_acquisition_gnss_synchro->PRN) << std::endl;
|
||||||
|
}
|
||||||
|
|
||||||
// Check lock status
|
// Check lock status
|
||||||
|
|
||||||
if (!cn0_and_tracking_lock_status(d_code_period))
|
if (!cn0_and_tracking_lock_status(d_code_period))
|
||||||
|
@ -124,6 +124,8 @@ private:
|
|||||||
int32_t d_preamble_length_symbols;
|
int32_t d_preamble_length_symbols;
|
||||||
boost::circular_buffer<float> d_symbol_history;
|
boost::circular_buffer<float> d_symbol_history;
|
||||||
|
|
||||||
|
// dll filter buffer
|
||||||
|
boost::circular_buffer<float> d_dll_filt_history;
|
||||||
// tracking state machine
|
// tracking state machine
|
||||||
int32_t d_state;
|
int32_t d_state;
|
||||||
|
|
||||||
@ -180,6 +182,7 @@ private:
|
|||||||
|
|
||||||
// tracking vars
|
// tracking vars
|
||||||
bool d_pull_in_transitory;
|
bool d_pull_in_transitory;
|
||||||
|
bool d_corrected_doppler;
|
||||||
double d_current_correlation_time_s;
|
double d_current_correlation_time_s;
|
||||||
double d_carr_phase_error_hz;
|
double d_carr_phase_error_hz;
|
||||||
double d_carr_freq_error_hz;
|
double d_carr_freq_error_hz;
|
||||||
|
@ -46,7 +46,8 @@ Dll_Pll_Conf_Fpga::Dll_Pll_Conf_Fpga()
|
|||||||
dump_filename = std::string("./dll_pll_dump.dat");
|
dump_filename = std::string("./dll_pll_dump.dat");
|
||||||
enable_fll_pull_in = false;
|
enable_fll_pull_in = false;
|
||||||
enable_fll_steady_state = false;
|
enable_fll_steady_state = false;
|
||||||
pull_in_time_s = 2;
|
pull_in_time_s = 10;
|
||||||
|
bit_synchronization_time_limit_s = pull_in_time_s + 60;
|
||||||
fll_filter_order = 1;
|
fll_filter_order = 1;
|
||||||
pll_filter_order = 3;
|
pll_filter_order = 3;
|
||||||
dll_filter_order = 2;
|
dll_filter_order = 2;
|
||||||
@ -66,6 +67,7 @@ Dll_Pll_Conf_Fpga::Dll_Pll_Conf_Fpga()
|
|||||||
cn0_min = 25;
|
cn0_min = 25;
|
||||||
max_lock_fail = 50;
|
max_lock_fail = 50;
|
||||||
carrier_lock_th = 0.85;
|
carrier_lock_th = 0.85;
|
||||||
|
enable_doppler_correction = false;
|
||||||
track_pilot = false;
|
track_pilot = false;
|
||||||
system = 'G';
|
system = 'G';
|
||||||
char sig_[3] = "1C";
|
char sig_[3] = "1C";
|
||||||
|
@ -46,6 +46,7 @@ public:
|
|||||||
bool enable_fll_pull_in;
|
bool enable_fll_pull_in;
|
||||||
bool enable_fll_steady_state;
|
bool enable_fll_steady_state;
|
||||||
unsigned int pull_in_time_s; // signed integer, when pull in time is not yet reached it has to be compared against a negative number
|
unsigned int pull_in_time_s; // signed integer, when pull in time is not yet reached it has to be compared against a negative number
|
||||||
|
unsigned int bit_synchronization_time_limit_s;
|
||||||
int pll_filter_order;
|
int pll_filter_order;
|
||||||
int dll_filter_order;
|
int dll_filter_order;
|
||||||
|
|
||||||
@ -74,6 +75,7 @@ public:
|
|||||||
uint32_t smoother_length;
|
uint32_t smoother_length;
|
||||||
double carrier_lock_th;
|
double carrier_lock_th;
|
||||||
bool track_pilot;
|
bool track_pilot;
|
||||||
|
bool enable_doppler_correction;
|
||||||
char system;
|
char system;
|
||||||
char signal[3];
|
char signal[3];
|
||||||
std::string device_name;
|
std::string device_name;
|
||||||
|
Loading…
Reference in New Issue
Block a user