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Major update to improve the GNSS-SDR pseudorange precision and correct some PVT bugs:

Browse Source 
- Updated all available trackings to generate the tracking_timestamp_secs taking into account the remainder code phase.
- Updated the telemetry decoder to track the number of symbol shifted from the preamble start symbol (to be used in observables).
- Updated observables to align the reference channel symbol with the corresponding symbols in the other channels and compute pseudorranges using the common transmission time algorithm.
- Updated PVT to independize the display output rate from the RINEX and KML log files. New options available in config file!
- Some minor improvements and code cleaning.

git-svn-id: https://svn.code.sf.net/p/gnss-sdr/code/trunk@193 64b25241-fba3-4117-9849-534c7e92360d
This commit is contained in:
Javier Arribas
2012-04-11 10:43:35 +00:00
parent 89a67c93e8
commit 9d34147e0f
33 changed files with 932 additions and 502 deletions
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200
src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_fll_pll_tracking_cc.cc
View File

@@ -113,10 +113,10 @@ Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc(
d_acquisition_gnss_synchro=NULL;
d_if_freq = if_freq;
d_fs_in = fs_in;
d_if_freq = (double)if_freq;
d_fs_in = (double)fs_in;
d_vector_length = vector_length;
d_early_late_spc_chips = early_late_space_chips; // Define early-late offset (in chips)
d_early_late_spc_chips = (double)early_late_space_chips; // Define early-late offset (in chips)
d_dump_filename = dump_filename;
// Initialize tracking variables ==========================================
@@ -144,10 +144,11 @@ Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc(
// sample synchronization
d_sample_counter = 0;
d_sample_counter_seconds = 0;
d_acq_sample_stamp = 0;
d_last_seg = 0;// this is for debug output only
d_code_phase_samples=0;
d_enable_tracking = false;
d_current_prn_length_samples = (int)d_vector_length;
@@ -181,31 +182,31 @@ void Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::start_tracking()
d_acq_sample_stamp = d_acquisition_gnss_synchro->Acq_samplestamp_samples;
unsigned long int acq_trk_diff_samples;
float acq_trk_diff_seconds;
double acq_trk_diff_seconds;
acq_trk_diff_samples = d_sample_counter - d_acq_sample_stamp;//-d_vector_length;
acq_trk_diff_seconds = (float)acq_trk_diff_samples / (float)d_fs_in;
acq_trk_diff_seconds = (double)acq_trk_diff_samples / d_fs_in;
//doppler effect
// Fd=(C/(C+Vr))*F
float radial_velocity;
double radial_velocity;
radial_velocity = (GPS_L1_FREQ_HZ + d_acq_carrier_doppler_hz) / GPS_L1_FREQ_HZ;
// 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;
double T_chip_mod_seconds;
double T_prn_mod_seconds;
double T_prn_mod_samples;
d_code_freq_hz = radial_velocity * GPS_L1_CA_CODE_RATE_HZ;
T_chip_mod_seconds = 1 / d_code_freq_hz;
T_prn_mod_seconds = T_chip_mod_seconds * GPS_L1_CA_CODE_LENGTH_CHIPS;
T_prn_mod_samples = T_prn_mod_seconds * (float)d_fs_in;
d_next_prn_length_samples = round(T_prn_mod_samples);
T_prn_mod_samples = T_prn_mod_seconds * d_fs_in;
d_current_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;
float T_prn_true_samples = T_prn_true_seconds * (float)d_fs_in;
float T_prn_diff_seconds;
double T_prn_true_seconds = GPS_L1_CA_CODE_LENGTH_CHIPS / GPS_L1_CA_CODE_RATE_HZ;
double T_prn_true_samples = T_prn_true_seconds * d_fs_in;
double T_prn_diff_seconds;
T_prn_diff_seconds = T_prn_true_seconds - T_prn_mod_seconds;
float N_prn_diff;
double N_prn_diff;
N_prn_diff = acq_trk_diff_seconds / T_prn_true_seconds;
float corrected_acq_phase_samples, delay_correction_samples;
corrected_acq_phase_samples = fmod((d_acq_code_phase_samples + T_prn_diff_seconds * N_prn_diff * (float)d_fs_in), T_prn_true_samples);
double corrected_acq_phase_samples, delay_correction_samples;
corrected_acq_phase_samples = fmod((d_acq_code_phase_samples + T_prn_diff_seconds * N_prn_diff * d_fs_in), T_prn_true_samples);
if (corrected_acq_phase_samples < 0)
{
@@ -231,11 +232,8 @@ void Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::start_tracking()
d_rem_carr_phase = 0;
d_FLL_discriminator_hz = 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;
sys = sys_.substr(0,1);
@@ -263,12 +261,12 @@ void Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::start_tracking()
void Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::update_local_code()
{
float tcode_chips;
float rem_code_phase_chips;
float code_phase_step_chips;
double tcode_chips;
double rem_code_phase_chips;
double code_phase_step_chips;
int associated_chip_index;
int code_length_chips = (int)GPS_L1_CA_CODE_LENGTH_CHIPS;
code_phase_step_chips = d_code_freq_hz / ((float)d_fs_in);
code_phase_step_chips = d_code_freq_hz / d_fs_in;
rem_code_phase_chips = d_rem_code_phase_samples * (d_code_freq_hz / d_fs_in);
// unified loop for E, P, L code vectors
tcode_chips = -rem_code_phase_chips;
@@ -282,7 +280,6 @@ void Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::update_local_code()
d_late_code[i] = d_ca_code[associated_chip_index];
tcode_chips = tcode_chips + code_phase_step_chips;
}
//d_code_phase_samples=d_code_phase_samples+(float)d_fs_in*GPS_L1_CA_CODE_LENGTH_CHIPS*(1/d_code_freq_hz-1/GPS_L1_CA_CODE_RATE_HZ);
}
@@ -291,8 +288,8 @@ void Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::update_local_code()
void Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::update_local_carrier()
{
float phase, phase_step;
phase_step = (float)GPS_TWO_PI * d_carrier_doppler_hz / (float)d_fs_in;
double phase, phase_step;
phase_step = GPS_TWO_PI * d_carrier_doppler_hz / d_fs_in;
phase = d_rem_carr_phase;
for(int i = 0; i < d_current_prn_length_samples; i++)
{
@@ -332,47 +329,52 @@ int Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::general_work (int noutput_items, gr_vecto
gr_vector_const_void_star &input_items, gr_vector_void_star &output_items)
{
float code_error_chips = 0;
float correlation_time_s = 0;
float PLL_discriminator_hz = 0;
float carr_nco_hz = 0;
double code_error_chips = 0;
double correlation_time_s = 0;
double PLL_discriminator_hz = 0;
double carr_nco_hz = 0;
// get the sample in and out pointers
const gr_complex* in = (gr_complex*) input_items[0]; //block input samples pointer
Gnss_Synchro **out = (Gnss_Synchro **) &output_items[0]; //block output streams pointer
d_Prompt_prev = *d_Prompt; // for the FLL discriminator
if (d_enable_tracking == true)
{
// GNSS_SYNCHRO OBJECT to interchange data between tracking->telemetry_decoder
Gnss_Synchro current_synchro_data;
// Fill the acquisition data
current_synchro_data=*d_acquisition_gnss_synchro;
/*
* Receiver signal alignment
*/
if (d_pull_in == true)
{
int samples_offset;
float acq_trk_shif_correction_samples;
double acq_trk_shif_correction_samples;
int acq_to_trk_delay_samples;
acq_to_trk_delay_samples = d_sample_counter-d_acq_sample_stamp;
acq_trk_shif_correction_samples = d_next_prn_length_samples - fmod((float)acq_to_trk_delay_samples, (float)d_next_prn_length_samples);
acq_trk_shif_correction_samples = d_current_prn_length_samples - fmod((double)acq_to_trk_delay_samples, (double)d_current_prn_length_samples);
samples_offset = round(d_acq_code_phase_samples + acq_trk_shif_correction_samples);
// /todo: Check if the sample counter sent to the next block as a time reference should be incremented AFTER sended or BEFORE
d_sample_counter_seconds = d_sample_counter_seconds + (((double)samples_offset)/(double)d_fs_in);
d_sample_counter = d_sample_counter + samples_offset; //count for the processed samples
d_pull_in = false;
consume_each(samples_offset); //shift input to perform alignment with local replica
// make an output to not stop the rest of the processing blocks
current_synchro_data.Prompt_I=0.0;
current_synchro_data.Prompt_Q=0.0;
current_synchro_data.Tracking_timestamp_secs=(double)d_sample_counter/d_fs_in;
current_synchro_data.Carrier_phase_rads=0.0;
current_synchro_data.Code_phase_secs=0.0;
current_synchro_data.CN0_dB_hz=0.0;
current_synchro_data.Flag_valid_tracking=false;
*out[0] =current_synchro_data;
return 1;
}
// GNSS_SYNCHRO OBJECT to interchange data between tracking->telemetry_decoder
Gnss_Synchro current_synchro_data;
// Fill the acquisition data
current_synchro_data=*d_acquisition_gnss_synchro;
// get the sample in and out pointers
const gr_complex* in = (gr_complex*) input_items[0]; //block input samples pointer
Gnss_Synchro **out = (Gnss_Synchro **) &output_items[0]; //block output streams pointer
// 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;
update_local_code();
update_local_carrier();
@@ -399,7 +401,7 @@ int Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::general_work (int noutput_items, gr_vecto
// make an output to not stop the rest of the processing blocks
current_synchro_data.Prompt_I=0.0;
current_synchro_data.Prompt_Q=0.0;
current_synchro_data.Tracking_timestamp_secs=d_sample_counter_seconds;
current_synchro_data.Tracking_timestamp_secs=(double)d_sample_counter/d_fs_in;
current_synchro_data.Carrier_phase_rads=0.0;
current_synchro_data.Code_phase_secs=0.0;
current_synchro_data.CN0_dB_hz=0.0;
@@ -417,7 +419,7 @@ int Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::general_work (int noutput_items, gr_vecto
code_error_chips = dll_nc_e_minus_l_normalized(*d_Early,*d_Late);
//compute FLL error
correlation_time_s = ((float)d_current_prn_length_samples) / (float)d_fs_in;
correlation_time_s = ((double)d_current_prn_length_samples) / d_fs_in;
if (d_FLL_wait == 1)
{
d_Prompt_prev = *d_Prompt;
@@ -425,18 +427,18 @@ int Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::general_work (int noutput_items, gr_vecto
}
else
{
d_FLL_discriminator_hz = fll_four_quadrant_atan(d_Prompt_prev, *d_Prompt, 0, correlation_time_s) / (float)GPS_TWO_PI;
d_FLL_discriminator_hz = fll_four_quadrant_atan(d_Prompt_prev, *d_Prompt, 0, correlation_time_s) / GPS_TWO_PI;
d_Prompt_prev = *d_Prompt;
d_FLL_wait = 1;
}
// Compute PLL error
PLL_discriminator_hz = pll_cloop_two_quadrant_atan(*d_Prompt) / (float)GPS_TWO_PI;
PLL_discriminator_hz = pll_cloop_two_quadrant_atan(*d_Prompt) / GPS_TWO_PI;
/*
* \todo Update FLL assistance algorithm!
*/
if ((((float)d_sample_counter - (float)d_acq_sample_stamp) / (float)d_fs_in) > 3)
if ((((double)d_sample_counter - (double)d_acq_sample_stamp) / d_fs_in) > 3)
{
d_FLL_discriminator_hz = 0; //disconnect the FLL after the initial lock
}
@@ -444,8 +446,8 @@ int Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::general_work (int noutput_items, gr_vecto
* DLL and FLL+PLL filter and get current carrier Doppler and code frequency
*/
carr_nco_hz = d_carrier_loop_filter.get_carrier_error(d_FLL_discriminator_hz, PLL_discriminator_hz, correlation_time_s);
d_carrier_doppler_hz = (float)d_if_freq + carr_nco_hz;
d_code_freq_hz = GPS_L1_CA_CODE_RATE_HZ - (((d_carrier_doppler_hz - (float)d_if_freq) * GPS_L1_CA_CODE_RATE_HZ) / GPS_L1_FREQ_HZ) - code_error_chips;
d_carrier_doppler_hz = d_if_freq + carr_nco_hz;
d_code_freq_hz = GPS_L1_CA_CODE_RATE_HZ - (((d_carrier_doppler_hz - d_if_freq) * GPS_L1_CA_CODE_RATE_HZ) / GPS_L1_FREQ_HZ) - code_error_chips;
/*!
* \todo Improve the lock detection algorithm!
@@ -475,8 +477,6 @@ int Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::general_work (int noutput_items, gr_vecto
if (d_carrier_lock_fail_counter > MAXIMUM_LOCK_FAIL_COUNTER)
{
std::cout << "Channel " << d_channel << " loss of lock!" << std::endl;
// tracking_message = 3; //loss of lock
// d_channel_internal_queue->push(tracking_message);
ControlMessageFactory* cmf = new ControlMessageFactory();
if (d_queue != gr_msg_queue_sptr()) {
d_queue->handle(cmf->GetQueueMessage(d_channel, 2));
@@ -487,16 +487,6 @@ int Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::general_work (int noutput_items, gr_vecto
}
}
// ########### Output the tracking data to navigation and PVT ##########
current_synchro_data.Prompt_I=(double)(*d_Prompt).real();
current_synchro_data.Prompt_Q=(double)(*d_Prompt).imag();
current_synchro_data.Tracking_timestamp_secs=d_sample_counter_seconds;
current_synchro_data.Carrier_phase_rads=(double)d_acc_carrier_phase_rad;
current_synchro_data.Code_phase_secs=(double)d_code_phase_samples * (1/(float)d_fs_in);
current_synchro_data.CN0_dB_hz=(double)d_CN0_SNV_dB_Hz;
*out[0] =current_synchro_data;
// ########## DEBUG OUTPUT
/*!
* \todo The stop timer has to be moved to the signal source!
@@ -508,11 +498,7 @@ int Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::general_work (int noutput_items, gr_vecto
{
d_last_seg = floor(d_sample_counter/d_fs_in);
std::cout << "Current input signal time = " << d_last_seg << " [s]" << std::endl;
//std::string sys = &d_acquisition_gnss_synchro->System;
//std::cout << sys << ", " << sys.substr(0,1) << std::endl;
std::cout << "Tracking CH " << d_channel << ": Satellite " << Gnss_Satellite(systemName[sys], d_acquisition_gnss_synchro->PRN) << ", CN0 = " << d_CN0_SNV_dB_Hz << " [dB-Hz]" << std::endl;
//std::cout<<"TRK CH "<<d_channel<<" Carrier_lock_test="<<d_carrier_lock_test<< std::endl;
//if (d_last_seg==5) d_carrier_lock_fail_counter=500; //DEBUG: force unlock!
}
}
else
@@ -520,35 +506,33 @@ int Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::general_work (int noutput_items, gr_vecto
if (floor(d_sample_counter/d_fs_in) != d_last_seg)
{
d_last_seg = floor(d_sample_counter/d_fs_in);
//std::string sys2 = &d_acquisition_gnss_synchro->System;
//std::cout << sys2 << ", " << sys2.substr(0,1) << std::endl;
std::cout << "Tracking CH " << d_channel << ": Satellite " << Gnss_Satellite(systemName[sys], d_acquisition_gnss_synchro->PRN) << ", CN0 = " << d_CN0_SNV_dB_Hz << " [dB-Hz]" << std::endl;
//std::cout<<"TRK CH "<<d_channel<<" Carrier_lock_test="<<d_carrier_lock_test<< std::endl;
}
}
//predict the next loop PRN period length prediction
float T_chip_seconds;
float T_prn_seconds;
float T_prn_samples;
float K_blk_samples;
double T_chip_seconds;
double T_prn_seconds;
double T_prn_samples;
double K_blk_samples;
T_chip_seconds = 1/d_code_freq_hz;
T_prn_seconds = T_chip_seconds * GPS_L1_CA_CODE_LENGTH_CHIPS;
T_prn_samples = T_prn_seconds * (float)d_fs_in;
d_rem_code_phase_samples = d_next_rem_code_phase_samples;
T_prn_samples = T_prn_seconds * d_fs_in;
K_blk_samples = T_prn_samples + d_rem_code_phase_samples;
d_current_prn_length_samples = round(K_blk_samples); //round to a discrete sample
d_rem_code_phase_samples = K_blk_samples - d_current_prn_length_samples; //rounding error
// Update the current PRN delay (code phase in samples)
float T_prn_true_seconds = GPS_L1_CA_CODE_LENGTH_CHIPS / GPS_L1_CA_CODE_RATE_HZ;
float T_prn_true_samples = T_prn_true_seconds * (float)d_fs_in;
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);
d_next_prn_length_samples = round(K_blk_samples); //round to a discrete sample
d_next_rem_code_phase_samples = K_blk_samples - d_next_prn_length_samples; //rounding error
// ########### Output the tracking data to navigation and PVT ##########
current_synchro_data.Prompt_I=(double)(*d_Prompt).imag();
current_synchro_data.Prompt_Q=(double)(*d_Prompt).real();
// Tracking_timestamp_secs is aligned with the PRN start sample
current_synchro_data.Tracking_timestamp_secs=((double)d_sample_counter+(double)d_current_prn_length_samples+d_rem_code_phase_samples)/d_fs_in;
// This tracking block aligns the Tracking_timestamp_secs with the start sample of the PRN, Code_phase_secs=0
current_synchro_data.Code_phase_secs=0;
current_synchro_data.Carrier_phase_rads=d_acc_carrier_phase_rad;
current_synchro_data.CN0_dB_hz=d_CN0_SNV_dB_Hz;
current_synchro_data.Flag_valid_tracking=true;
*out[0] =current_synchro_data;
}
else
{
@@ -567,6 +551,7 @@ int Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::general_work (int noutput_items, gr_vecto
float prompt_Q;
float tmp_E, tmp_P, tmp_L;
float tmp_float;
double tmp_double;
prompt_I = (*d_Prompt).imag();
prompt_Q = (*d_Prompt).real();
tmp_E=std::abs<float>(*d_Early);
@@ -585,28 +570,38 @@ int Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::general_work (int noutput_items, gr_vecto
//tmp_float=(float)d_sample_counter;
d_dump_file.write((char*)&d_sample_counter, sizeof(unsigned long int));
// accumulated carrier phase
d_dump_file.write((char*)&d_acc_carrier_phase_rad, sizeof(float));
tmp_float=(float)d_acc_carrier_phase_rad;
d_dump_file.write((char*)&tmp_float, sizeof(float));
// carrier and code frequency
d_dump_file.write((char*)&d_carrier_doppler_hz, sizeof(float));
d_dump_file.write((char*)&d_code_freq_hz, sizeof(float));
tmp_float=(float)d_carrier_doppler_hz;
d_dump_file.write((char*)&tmp_float, sizeof(float));
tmp_float=(float)d_code_freq_hz;
d_dump_file.write((char*)&tmp_float, sizeof(float));
//PLL commands
d_dump_file.write((char*)&PLL_discriminator_hz, sizeof(float));
d_dump_file.write((char*)&carr_nco_hz, sizeof(float));
tmp_float=(float)PLL_discriminator_hz;
d_dump_file.write((char*)&tmp_float, sizeof(float));
tmp_float=(float)carr_nco_hz;
d_dump_file.write((char*)&tmp_float, sizeof(float));
//DLL commands
d_dump_file.write((char*)&code_error_chips, sizeof(float));
d_dump_file.write((char*)&d_code_phase_samples, sizeof(float));
tmp_float=(float)code_error_chips;
d_dump_file.write((char*)&tmp_float, sizeof(float));
tmp_float=(float)d_code_phase_samples;
d_dump_file.write((char*)&tmp_float, sizeof(float));
// CN0 and carrier lock test
d_dump_file.write((char*)&d_CN0_SNV_dB_Hz, sizeof(float));
d_dump_file.write((char*)&d_carrier_lock_test, sizeof(float));
tmp_float=(float)d_CN0_SNV_dB_Hz;
d_dump_file.write((char*)&tmp_float, sizeof(float));
tmp_float=(float)d_carrier_lock_test;
d_dump_file.write((char*)&tmp_float, sizeof(float));
// AUX vars (for debug purposes)
tmp_float = 0;
tmp_float = (float)d_rem_code_phase_samples;
d_dump_file.write((char*)&tmp_float, sizeof(float));
d_dump_file.write((char*)&d_sample_counter_seconds, sizeof(double));
tmp_double=(double)(d_sample_counter+d_current_prn_length_samples);
d_dump_file.write((char*)&tmp_double, sizeof(double));
}
catch (std::ifstream::failure e)
{
@@ -614,7 +609,6 @@ int Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::general_work (int noutput_items, gr_vecto
}
}
consume_each(d_current_prn_length_samples); // this is necesary in gr_block derivates
d_sample_counter_seconds = d_sample_counter_seconds + (((double)d_current_prn_length_samples) / (double)d_fs_in);
d_sample_counter += d_current_prn_length_samples; //count for the processed samples
return 1; //output tracking result ALWAYS even in the case of d_enable_tracking==false
}

35
src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_fll_pll_tracking_cc.h
View File

@@ -142,8 +142,8 @@ private:
bool d_dump;
unsigned int d_channel;
int d_last_seg;
long d_if_freq;
long d_fs_in;
double d_if_freq;
double d_fs_in;
gr_complex* d_ca_code;
@@ -159,44 +159,43 @@ private:
gr_complex d_Prompt_prev;
float d_early_late_spc_chips;
double d_early_late_spc_chips;
float d_carrier_doppler_hz;
float d_code_freq_hz;
float d_code_phase_samples;
double d_carrier_doppler_hz;
double d_code_freq_hz;
double d_code_phase_samples;
int d_current_prn_length_samples;
int d_next_prn_length_samples;
//int d_next_prn_length_samples;
int d_FLL_wait;
float d_rem_carr_phase;
float d_rem_code_phase_samples;
float d_next_rem_code_phase_samples;
double d_rem_carr_phase;
double d_rem_code_phase_samples;
//double d_next_rem_code_phase_samples;
bool d_pull_in;
// acquisition
float d_acq_code_phase_samples;
float d_acq_carrier_doppler_hz;
double d_acq_code_phase_samples;
double d_acq_carrier_doppler_hz;
// correlator
Correlator d_correlator;
// FLL + PLL filter
float d_FLL_discriminator_hz; // This is a class variable because FLL needs to have memory
double d_FLL_discriminator_hz; // This is a class variable because FLL needs to have memory
Tracking_FLL_PLL_filter d_carrier_loop_filter;
float d_acc_carrier_phase_rad;
double d_acc_carrier_phase_rad;
unsigned long int d_sample_counter;
double d_sample_counter_seconds;
unsigned long int d_acq_sample_stamp;
// CN0 estimation and lock detector
int d_cn0_estimation_counter;
gr_complex* d_Prompt_buffer;
float d_carrier_lock_test;
float d_CN0_SNV_dB_Hz;
double d_carrier_lock_test;
double d_CN0_SNV_dB_Hz;
float d_carrier_lock_threshold;
double d_carrier_lock_threshold;
int d_carrier_lock_fail_counter;

39
src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_pll_tracking_cc.cc
View File

@@ -154,7 +154,7 @@ Gps_L1_Ca_Dll_Pll_Tracking_cc::Gps_L1_Ca_Dll_Pll_Tracking_cc(
// sample synchronization
d_sample_counter = 0;
d_sample_counter_seconds = 0;
//d_sample_counter_seconds = 0;
d_acq_sample_stamp = 0;
d_enable_tracking = false;
@@ -322,10 +322,6 @@ Gps_L1_Ca_Dll_Pll_Tracking_cc::~Gps_L1_Ca_Dll_Pll_Tracking_cc()
}
/* Tracking signal processing
* Notice that this is a class derived from gr_sync_decimator, so each of the ninput_items has vector_length samples
*/
@@ -357,7 +353,7 @@ int Gps_L1_Ca_Dll_Pll_Tracking_cc::general_work (int noutput_items, gr_vector_in
//std::cout<<"acq_trk_shif_correction="<<acq_trk_shif_correction_samples<<"\r\n";
samples_offset = round(d_acq_code_phase_samples + acq_trk_shif_correction_samples);
// /todo: Check if the sample counter sent to the next block as a time reference should be incremented AFTER sended or BEFORE
d_sample_counter_seconds = d_sample_counter_seconds + (((double)samples_offset) / (double)d_fs_in);
//d_sample_counter_seconds = d_sample_counter_seconds + (((double)samples_offset) / (double)d_fs_in);
d_sample_counter = d_sample_counter + samples_offset; //count for the processed samples
d_pull_in = false;
//std::cout<<" samples_offset="<<samples_offset<<"\r\n";
@@ -403,7 +399,7 @@ int Gps_L1_Ca_Dll_Pll_Tracking_cc::general_work (int noutput_items, gr_vector_in
// make an output to not stop the rest of the processing blocks
current_synchro_data.Prompt_I=0.0;
current_synchro_data.Prompt_Q=0.0;
current_synchro_data.Tracking_timestamp_secs=d_sample_counter_seconds;
current_synchro_data.Tracking_timestamp_secs=(double)d_sample_counter/(double)d_fs_in;
current_synchro_data.Carrier_phase_rads=0.0;
current_synchro_data.Code_phase_secs=0.0;
current_synchro_data.CN0_dB_hz=0.0;
@@ -441,17 +437,6 @@ int Gps_L1_Ca_Dll_Pll_Tracking_cc::general_work (int noutput_items, gr_vector_in
T_prn_samples = T_prn_seconds * d_fs_in;
d_rem_code_phase_samples = d_next_rem_code_phase_samples;
K_blk_samples = T_prn_samples + d_rem_code_phase_samples;
// Update the current PRN delay (code phase in samples)
float T_prn_true_seconds = GPS_L1_CA_CODE_LENGTH_CHIPS / GPS_L1_CA_CODE_RATE_HZ;
float T_prn_true_samples = T_prn_true_seconds * (float)d_fs_in;
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);
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
@@ -499,11 +484,13 @@ int Gps_L1_Ca_Dll_Pll_Tracking_cc::general_work (int noutput_items, gr_vector_in
// ########### Output the tracking data to navigation and PVT ##########
current_synchro_data.Prompt_I = (double)(*d_Prompt).real();
current_synchro_data.Prompt_Q = (double)(*d_Prompt).imag();
current_synchro_data.Tracking_timestamp_secs = d_sample_counter_seconds;
current_synchro_data.Prompt_I = (double)(*d_Prompt).imag();
current_synchro_data.Prompt_Q = (double)(*d_Prompt).real();
// Tracking_timestamp_secs is aligned with the PRN start sample
current_synchro_data.Tracking_timestamp_secs=((double)d_sample_counter+(double)d_next_prn_length_samples+(double)d_next_rem_code_phase_samples)/(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 = (double)d_acc_carrier_phase_rad;
current_synchro_data.Code_phase_secs = (double)d_code_phase_samples * (1/(float)d_fs_in);
current_synchro_data.CN0_dB_hz = (double)d_CN0_SNV_dB_Hz;
*out[0] = current_synchro_data;
@@ -554,6 +541,7 @@ int Gps_L1_Ca_Dll_Pll_Tracking_cc::general_work (int noutput_items, gr_vector_in
float prompt_Q;
float tmp_E, tmp_P, tmp_L;
float tmp_float;
double tmp_double;
prompt_I = (*d_Prompt).imag();
prompt_Q = (*d_Prompt).real();
tmp_E = std::abs<float>(*d_Early);
@@ -591,9 +579,10 @@ int Gps_L1_Ca_Dll_Pll_Tracking_cc::general_work (int noutput_items, gr_vector_in
d_dump_file.write((char*)&d_carrier_lock_test, sizeof(float));
// AUX vars (for debug purposes)
tmp_float=0;
tmp_float = d_rem_code_phase_samples;
d_dump_file.write((char*)&tmp_float, sizeof(float));
d_dump_file.write((char*)&d_sample_counter_seconds, sizeof(double));
tmp_double=(double)(d_sample_counter+d_current_prn_length_samples);
d_dump_file.write((char*)&tmp_double, sizeof(double));
}
catch (std::ifstream::failure e)
{
@@ -602,7 +591,7 @@ int Gps_L1_Ca_Dll_Pll_Tracking_cc::general_work (int noutput_items, gr_vector_in
}
consume_each(d_current_prn_length_samples); // this is necesary in gr_block derivates
d_sample_counter_seconds = d_sample_counter_seconds + ( ((double)d_current_prn_length_samples) / (double)d_fs_in );
//d_sample_counter_seconds = d_sample_counter_seconds + ( ((double)d_current_prn_length_samples) / (double)d_fs_in );
d_sample_counter += d_current_prn_length_samples; //count for the processed samples
return 1; //output tracking result ALWAYS even in the case of d_enable_tracking==false
}

2
src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_pll_tracking_cc.h
View File

@@ -172,7 +172,7 @@ private:
//PRN period in samples
int d_current_prn_length_samples;
int d_next_prn_length_samples;
double d_sample_counter_seconds;
//double d_sample_counter_seconds;
//processing samples counters
unsigned long int d_sample_counter;

42
src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_tcp_connector_tracking_cc.cc
View File

@@ -483,17 +483,6 @@ int Gps_L1_Ca_Tcp_Connector_Tracking_cc::general_work (int noutput_items, gr_vec
T_prn_samples = T_prn_seconds * d_fs_in;
d_rem_code_phase_samples = d_next_rem_code_phase_samples;
K_blk_samples = T_prn_samples + d_rem_code_phase_samples;
// Update the current PRN delay (code phase in samples)
float T_prn_true_seconds = GPS_L1_CA_CODE_LENGTH_CHIPS / GPS_L1_CA_CODE_RATE_HZ;
float T_prn_true_samples = T_prn_true_seconds * (float)d_fs_in;
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);
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
@@ -539,16 +528,6 @@ int Gps_L1_Ca_Tcp_Connector_Tracking_cc::general_work (int noutput_items, gr_vec
//std::cout<<"d_carrier_lock_fail_counter"<<d_carrier_lock_fail_counter<<"\r\n";
}
// ########### Output the tracking data to navigation and PVT ##########
current_synchro_data.Prompt_I = (double)(*d_Prompt).real();
current_synchro_data.Prompt_Q = (double)(*d_Prompt).imag();
current_synchro_data.Tracking_timestamp_secs = d_sample_counter_seconds;
current_synchro_data.Carrier_phase_rads = (double)d_acc_carrier_phase_rad;
current_synchro_data.Code_phase_secs = (double)d_code_phase_samples * (1/(float)d_fs_in);
current_synchro_data.CN0_dB_hz = (double)d_CN0_SNV_dB_Hz;
*out[0] = current_synchro_data;
// ########## DEBUG OUTPUT
/*!
* \todo The stop timer has to be moved to the signal source!
@@ -576,6 +555,19 @@ int Gps_L1_Ca_Tcp_Connector_Tracking_cc::general_work (int noutput_items, gr_vec
//std::cout<<"TRK CH "<<d_channel<<" Carrier_lock_test="<<d_carrier_lock_test<< std::endl;
}
}
// ########### Output the tracking data to navigation and PVT ##########
current_synchro_data.Prompt_I = (double)(*d_Prompt).real();
current_synchro_data.Prompt_Q = (double)(*d_Prompt).imag();
// Tracking_timestamp_secs is aligned with the PRN start sample
current_synchro_data.Tracking_timestamp_secs=((double)d_sample_counter+(double)d_next_prn_length_samples+(double)d_next_rem_code_phase_samples)/(double)d_fs_in;
// This tracking block aligns the Tracking_timestamp_secs with the start sample of the PRN, Code_phase_secs=0
current_synchro_data.Code_phase_secs=0;
current_synchro_data.Tracking_timestamp_secs = d_sample_counter_seconds;
current_synchro_data.Carrier_phase_rads = (double)d_acc_carrier_phase_rad;
current_synchro_data.CN0_dB_hz = (double)d_CN0_SNV_dB_Hz;
*out[0] = current_synchro_data;
}
else
{
@@ -600,6 +592,7 @@ int Gps_L1_Ca_Tcp_Connector_Tracking_cc::general_work (int noutput_items, gr_vec
float prompt_Q;
float tmp_E, tmp_P, tmp_L;
float tmp_float;
double tmp_double;
prompt_I = (*d_Prompt).imag();
prompt_Q = (*d_Prompt).real();
tmp_E = std::abs<float>(*d_Early);
@@ -637,9 +630,10 @@ int Gps_L1_Ca_Tcp_Connector_Tracking_cc::general_work (int noutput_items, gr_vec
d_dump_file.write((char*)&d_carrier_lock_test, sizeof(float));
// AUX vars (for debug purposes)
tmp_float=0;
tmp_float = d_rem_code_phase_samples;
d_dump_file.write((char*)&tmp_float, sizeof(float));
d_dump_file.write((char*)&d_sample_counter_seconds, sizeof(double));
tmp_double=(double)(d_sample_counter+d_current_prn_length_samples);
d_dump_file.write((char*)&tmp_double, sizeof(double));
}
catch (std::ifstream::failure e)
{
@@ -648,7 +642,7 @@ int Gps_L1_Ca_Tcp_Connector_Tracking_cc::general_work (int noutput_items, gr_vec
}
consume_each(d_current_prn_length_samples); // this is necesary in gr_block derivates
d_sample_counter_seconds = d_sample_counter_seconds + ( ((double)d_current_prn_length_samples) / (double)d_fs_in );
//d_sample_counter_seconds = d_sample_counter_seconds + ( ((double)d_current_prn_length_samples) / (double)d_fs_in );
d_sample_counter += d_current_prn_length_samples; //count for the processed samples
return 1; //output tracking result ALWAYS even in the case of d_enable_tracking==false
}