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Merge branch next_gps_20ms_corr with next. Removing obsolete code and code cleaning

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This commit is contained in:
Javier Arribas
2016-03-30 15:03:25 +02:00
parent 1b9516fa8b d15066fda6
commit b2034896e1
36 changed files with 768 additions and 1001 deletions
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12
src/algorithms/tracking/adapters/gps_l1_ca_dll_pll_c_aid_tracking.cc
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@@ -60,7 +60,9 @@ GpsL1CaDllPllCAidTracking::GpsL1CaDllPllCAidTracking(
std::string dump_filename;
std::string default_item_type = "gr_complex";
float pll_bw_hz;
float pll_bw_narrow_hz;
float dll_bw_hz;
float dll_bw_narrow_hz;
float early_late_space_chips;
item_type_ = configuration->property(role + ".item_type", default_item_type);
//vector_length = configuration->property(role + ".vector_length", 2048);
@@ -69,6 +71,11 @@ GpsL1CaDllPllCAidTracking::GpsL1CaDllPllCAidTracking(
dump = configuration->property(role + ".dump", false);
pll_bw_hz = configuration->property(role + ".pll_bw_hz", 50.0);
dll_bw_hz = configuration->property(role + ".dll_bw_hz", 2.0);
pll_bw_narrow_hz = configuration->property(role + ".pll_bw_narrow_hz", 20.0);
dll_bw_narrow_hz = configuration->property(role + ".dll_bw_narrow_hz", 2.0);
int extend_correlation_ms;
extend_correlation_ms = configuration->property(role + ".extend_correlation_ms", 1);
early_late_space_chips = configuration->property(role + ".early_late_space_chips", 0.5);
std::string default_dump_filename = "./track_ch";
dump_filename = configuration->property(role + ".dump_filename",
@@ -88,6 +95,9 @@ GpsL1CaDllPllCAidTracking::GpsL1CaDllPllCAidTracking(
dump_filename,
pll_bw_hz,
dll_bw_hz,
pll_bw_narrow_hz,
dll_bw_narrow_hz,
extend_correlation_ms,
early_late_space_chips);
DLOG(INFO) << "tracking(" << tracking_cc->unique_id() << ")";
}else if(item_type_.compare("cshort") == 0)
@@ -102,6 +112,8 @@ GpsL1CaDllPllCAidTracking::GpsL1CaDllPllCAidTracking(
dump_filename,
pll_bw_hz,
dll_bw_hz,
pll_bw_narrow_hz,
dll_bw_narrow_hz,
early_late_space_chips);
DLOG(INFO) << "tracking(" << tracking_sc->unique_id() << ")";
}else

2
src/algorithms/tracking/gnuradio_blocks/galileo_e1_dll_pll_veml_tracking_cc.cc
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@@ -105,6 +105,8 @@ galileo_e1_dll_pll_veml_tracking_cc::galileo_e1_dll_pll_veml_tracking_cc(
gr::block("galileo_e1_dll_pll_veml_tracking_cc", gr::io_signature::make(1, 1, sizeof(gr_complex)),
gr::io_signature::make(1, 1, sizeof(Gnss_Synchro)))
{
// Telemetry bit synchronization message port input
this->message_port_register_in(pmt::mp("preamble_timestamp_s"));
this->set_relative_rate(1.0/vector_length);
// initialize internal vars
d_queue = queue;

3
src/algorithms/tracking/gnuradio_blocks/galileo_e1_tcp_connector_tracking_cc.cc
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@@ -108,6 +108,9 @@ Galileo_E1_Tcp_Connector_Tracking_cc::Galileo_E1_Tcp_Connector_Tracking_cc(
gr::block("Galileo_E1_Tcp_Connector_Tracking_cc", gr::io_signature::make(1, 1, sizeof(gr_complex)),
gr::io_signature::make(1, 1, sizeof(Gnss_Synchro)))
{
// Telemetry bit synchronization message port input
this->message_port_register_in(pmt::mp("preamble_timestamp_s"));
this->set_relative_rate(1.0/vector_length);
// initialize internal vars
d_queue = queue;

3
src/algorithms/tracking/gnuradio_blocks/galileo_e5a_dll_pll_tracking_cc.cc
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@@ -108,6 +108,9 @@ Galileo_E5a_Dll_Pll_Tracking_cc::Galileo_E5a_Dll_Pll_Tracking_cc(
gr::block("Galileo_E5a_Dll_Pll_Tracking_cc", gr::io_signature::make(1, 1, sizeof(gr_complex)),
gr::io_signature::make(1, 1, sizeof(Gnss_Synchro)))
{
// Telemetry bit synchronization message port input
this->message_port_register_in(pmt::mp("preamble_timestamp_s"));
this->set_relative_rate(1.0/vector_length);
// initialize internal vars
d_queue = queue;

15
src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_fll_pll_tracking_cc.cc
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@@ -105,6 +105,8 @@ Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc(
gr::block("Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc", gr::io_signature::make(1, 1, sizeof(gr_complex)),
gr::io_signature::make(1, 1, sizeof(Gnss_Synchro)))
{
// Telemetry bit synchronization message port input
this->message_port_register_in(pmt::mp("preamble_timestamp_s"));
// initialize internal vars
d_queue = queue;
d_dump = dump;
@@ -290,16 +292,6 @@ void Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::update_local_code()
memcpy(d_prompt_code,&d_early_code[early_late_spc_samples],d_current_prn_length_samples* sizeof(gr_complex));
memcpy(d_late_code,&d_early_code[early_late_spc_samples*2],d_current_prn_length_samples* sizeof(gr_complex));
// for (int i=0; i<d_current_prn_length_samples; i++)
// {
// associated_chip_index = 1 + round(fmod(tcode_chips - d_early_late_spc_chips, code_length_chips));
// d_early_code[i] = d_ca_code[associated_chip_index];
// associated_chip_index = 1 + round(fmod(tcode_chips, code_length_chips));
// d_prompt_code[i] = d_ca_code[associated_chip_index];
// associated_chip_index = 1 + round(fmod(tcode_chips + d_early_late_spc_chips, code_length_chips));
// d_late_code[i] = d_ca_code[associated_chip_index];
// tcode_chips = tcode_chips + code_phase_step_chips;
// }
}
@@ -555,6 +547,8 @@ int Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::general_work (int noutput_items, gr_vecto
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_tracking = true;
current_synchro_data.Flag_valid_symbol_output = true;
current_synchro_data.correlation_length_ms=1;
current_synchro_data.Flag_valid_pseudorange = false;
*out[0] = current_synchro_data;
}
@@ -583,6 +577,7 @@ int Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::general_work (int noutput_items, gr_vecto
Gnss_Synchro **out = (Gnss_Synchro **) &output_items[0]; //block output streams pointer
d_acquisition_gnss_synchro->Flag_valid_pseudorange = false;
d_acquisition_gnss_synchro->Flag_valid_symbol_output = false;
*out[0] = *d_acquisition_gnss_synchro;
}

381
src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_pll_c_aid_tracking_cc.cc
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@@ -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"
@@ -65,10 +67,13 @@ gps_l1_ca_dll_pll_c_aid_make_tracking_cc(
std::string dump_filename,
float pll_bw_hz,
float dll_bw_hz,
float pll_bw_narrow_hz,
float dll_bw_narrow_hz,
int extend_correlation_ms,
float early_late_space_chips)
{
return gps_l1_ca_dll_pll_c_aid_tracking_cc_sptr(new gps_l1_ca_dll_pll_c_aid_tracking_cc(if_freq,
fs_in, vector_length, queue, dump, dump_filename, pll_bw_hz, dll_bw_hz, early_late_space_chips));
fs_in, vector_length, queue, dump, dump_filename, pll_bw_hz, dll_bw_hz,pll_bw_narrow_hz, dll_bw_narrow_hz, extend_correlation_ms, early_late_space_chips));
}
@@ -82,6 +87,17 @@ 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 enabled for Tracking CH " << d_channel << ": Satellite " << Gnss_Satellite(systemName[sys], d_acquisition_gnss_synchro->PRN)<< std::endl;
if (d_enable_extended_integration==false) //avoid re-setting preamble indicator
{
d_preamble_timestamp_s=pmt::to_double(msg);
d_enable_extended_integration=true;
d_preamble_synchronized=false;
}
}
gps_l1_ca_dll_pll_c_aid_tracking_cc::gps_l1_ca_dll_pll_c_aid_tracking_cc(
@@ -93,10 +109,20 @@ gps_l1_ca_dll_pll_c_aid_tracking_cc::gps_l1_ca_dll_pll_c_aid_tracking_cc(
std::string dump_filename,
float pll_bw_hz,
float dll_bw_hz,
float pll_bw_narrow_hz,
float dll_bw_narrow_hz,
int extend_correlation_ms,
float early_late_space_chips) :
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)))
{
// Telemetry bit synchronization message port input
this->message_port_register_in(pmt::mp("preamble_timestamp_s"));
this->set_msg_handler(pmt::mp("preamble_timestamp_s"),
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 +133,13 @@ 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_pll_bw_narrow_hz=pll_bw_narrow_hz;
d_dll_bw_narrow_hz=dll_bw_narrow_hz;
d_extend_correlation_ms = extend_correlation_ms;
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 +172,8 @@ 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)
//d_sample_counter_seconds = 0;
d_acq_sample_stamp = 0;
@@ -168,6 +200,7 @@ gps_l1_ca_dll_pll_c_aid_tracking_cc::gps_l1_ca_dll_pll_c_aid_tracking_cc(
d_acq_code_phase_samples = 0.0;
d_acq_carrier_doppler_hz = 0.0;
d_carrier_doppler_hz = 0.0;
d_code_error_filt_chips_Ti = 0.0;
d_acc_carrier_phase_cycles = 0.0;
d_code_phase_samples = 0.0;
@@ -175,6 +208,8 @@ 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_extended_integration=false;
d_preamble_synchronized=false;
//set_min_output_buffer((long int)300);
}
@@ -258,7 +293,8 @@ void gps_l1_ca_dll_pll_c_aid_tracking_cc::start_tracking()
// enable tracking
d_pull_in = true;
d_enable_tracking = true;
d_enable_extended_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;
@@ -290,13 +326,10 @@ int gps_l1_ca_dll_pll_c_aid_tracking_cc::general_work (int noutput_items, gr_vec
Gnss_Synchro current_synchro_data = Gnss_Synchro();
// process vars
double code_error_chips_Ti = 0.0;
double code_error_filt_chips = 0.0;
double code_error_filt_secs_Ti = 0.0;
double CURRENT_INTEGRATION_TIME_S;
double CORRECTED_INTEGRATION_TIME_S;
double CURRENT_INTEGRATION_TIME_S = 0.0;
double CORRECTED_INTEGRATION_TIME_S = 0.0;
double dll_code_error_secs_Ti = 0.0;
double carr_phase_error_secs_Ti = 0.0;
double old_d_rem_code_phase_samples;
if (d_enable_tracking == true)
{
@@ -313,6 +346,8 @@ int gps_l1_ca_dll_pll_c_aid_tracking_cc::general_work (int noutput_items, gr_vec
d_pull_in = false;
// Fill the acquisition data
current_synchro_data = *d_acquisition_gnss_synchro;
current_synchro_data.correlation_length_ms=1;
current_synchro_data.Flag_valid_symbol_output = false;
*out[0] = current_synchro_data;
consume_each(samples_offset); //shift input to perform alignment with local replica
return 1;
@@ -326,115 +361,228 @@ 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);
// ####### coherent intergration extension
// keep the last symbols
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 (static_cast<int>(d_P_history.size())>d_extend_correlation_ms)
{
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_extended_integration==true)
{
long int symbol_diff=round(1000.0*((static_cast<double>(d_sample_counter) + d_rem_code_phase_samples) / static_cast<double>(d_fs_in)-d_preamble_timestamp_s));
if (symbol_diff>0 and symbol_diff % d_extend_correlation_ms == 0)
{
// compute coherent integration and enable tracking loop
// perform coherent integration using correlator output history
//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<d_extend_correlation_ms;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_code_loop_filter.set_DLL_BW(d_dll_bw_narrow_hz);
d_carrier_loop_filter.set_params(10.0, d_pll_bw_narrow_hz,2);
d_preamble_synchronized=true;
std::cout<<"Enabled extended correlator for CH "<< d_channel <<" : Satellite " << Gnss_Satellite(systemName[sys], d_acquisition_gnss_synchro->PRN)
<<" dll_narrow_bw="<<d_dll_bw_narrow_hz<<" pll_narrow_bw="<<d_pll_bw_narrow_hz<<std::endl;
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
}
// UPDATE INTEGRATION TIME
CURRENT_INTEGRATION_TIME_S = static_cast<double>(d_extend_correlation_ms)*GPS_L1_CA_CODE_PERIOD;
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;
}else{
if(d_preamble_synchronized==true)
{
// continue extended coherent correlation
//remnant carrier phase [rads]
d_rem_carrier_phase_rad = fmod(d_rem_carrier_phase_rad + d_carrier_phase_step_rad * static_cast<double>(d_correlation_length_samples), GPS_TWO_PI);
//################### 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);
// Compute the next buffer length based on the period of the PRN sequence and the code phase error estimation
double T_chip_seconds = 1 / d_code_freq_chips;
double T_prn_seconds = T_chip_seconds * GPS_L1_CA_CODE_LENGTH_CHIPS;
double T_prn_samples = T_prn_seconds * static_cast<double>(d_fs_in);
int K_prn_samples = round(T_prn_samples);
double K_T_prn_error_samples=K_prn_samples-T_prn_samples;
//################### 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));
d_rem_code_phase_samples= d_rem_code_phase_samples - K_T_prn_error_samples;
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;
//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
}
}
// UPDATE ACCUMULATED CARRIER PHASE
CORRECTED_INTEGRATION_TIME_S=(static_cast<double>(d_correlation_length_samples)/static_cast<double>(d_fs_in));
d_acc_carrier_phase_cycles -= d_carrier_doppler_hz * CORRECTED_INTEGRATION_TIME_S;
// ########### 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;
// 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{
// UPDATE INTEGRATION TIME
CURRENT_INTEGRATION_TIME_S = static_cast<double>(d_correlation_length_samples) / static_cast<double>(d_fs_in);
enable_dll_pll=true;
}
if (enable_dll_pll==true)
{
// ################## PLL ##########################################################
// Update PLL discriminator [rads/Ti -> Secs/Ti]
d_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, d_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 ##########################################################
// DLL discriminator
d_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
d_code_error_filt_chips_s = d_code_loop_filter.get_code_nco(d_code_error_chips_Ti); //input [chips/Ti] -> output [chips/second]
d_code_error_filt_chips_Ti = d_code_error_filt_chips_s*CURRENT_INTEGRATION_TIME_S;
code_error_filt_secs_Ti = d_code_error_filt_chips_Ti/d_code_freq_chips; // [s/Ti]
// DLL code error estimation [s/Ti]
// PLL to DLL assistance is disable due to the use of a fractional resampler that allows the correction of the code Doppler effect.
dll_code_error_secs_Ti = - code_error_filt_secs_Ti;// + d_pll_to_dll_assist_secs_Ti;
// ################## 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_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 ACCUMULATED 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;
if (d_preamble_synchronized==true)
{
current_synchro_data.correlation_length_ms=d_extend_correlation_ms;
}else{
current_synchro_data.correlation_length_ms=1;
}
*out[0] = current_synchro_data;
}else{
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;
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;
current_synchro_data.Flag_valid_symbol_output = false;
current_synchro_data.correlation_length_ms=1;
*out[0] = current_synchro_data;
}
// ########## DEBUG OUTPUT
/*!
@@ -447,7 +595,7 @@ int gps_l1_ca_dll_pll_c_aid_tracking_cc::general_work (int noutput_items, gr_vec
{
d_last_seg = floor(d_sample_counter / d_fs_in);
std::cout << "Current input signal time = " << d_last_seg << " [s]" << std::endl;
DLOG(INFO) << "GPS L1 C/A Tracking CH " << d_channel << ": Satellite " << Gnss_Satellite(systemName[sys], d_acquisition_gnss_synchro->PRN)
DLOG(INFO) << "GPS L1 C/A Tracking CH " << d_channel << ": Satellite " << Gnss_Satellite(systemName[sys], d_acquisition_gnss_synchro->PRN)
<< ", CN0 = " << d_CN0_SNV_dB_Hz << " [dB-Hz]" << std::endl;
//if (d_last_seg==5) d_carrier_lock_fail_counter=500; //DEBUG: force unlock!
}
@@ -457,7 +605,7 @@ int gps_l1_ca_dll_pll_c_aid_tracking_cc::general_work (int noutput_items, gr_vec
if (floor(d_sample_counter / d_fs_in) != d_last_seg)
{
d_last_seg = floor(d_sample_counter / d_fs_in);
DLOG(INFO) << "Tracking CH " << d_channel << ": Satellite " << Gnss_Satellite(systemName[sys], d_acquisition_gnss_synchro->PRN)
DLOG(INFO) << "Tracking CH " << d_channel << ": Satellite " << Gnss_Satellite(systemName[sys], d_acquisition_gnss_synchro->PRN)
<< ", CN0 = " << d_CN0_SNV_dB_Hz << " [dB-Hz]";
}
}
@@ -488,6 +636,7 @@ int gps_l1_ca_dll_pll_c_aid_tracking_cc::general_work (int noutput_items, gr_vec
current_synchro_data.System = {'G'};
current_synchro_data.Flag_valid_pseudorange = false;
current_synchro_data.correlation_length_ms=1;
*out[0] = current_synchro_data;
}
@@ -523,19 +672,19 @@ int gps_l1_ca_dll_pll_c_aid_tracking_cc::general_work (int noutput_items, gr_vec
d_dump_file.write(reinterpret_cast<char*>(&d_code_freq_chips), sizeof(double));
//PLL commands
d_dump_file.write(reinterpret_cast<char*>(&carr_phase_error_secs_Ti), sizeof(double));
d_dump_file.write(reinterpret_cast<char*>(&d_carr_phase_error_secs_Ti), sizeof(double));
d_dump_file.write(reinterpret_cast<char*>(&d_carrier_doppler_hz), sizeof(double));
//DLL commands
d_dump_file.write(reinterpret_cast<char*>(&code_error_chips_Ti), sizeof(double));
d_dump_file.write(reinterpret_cast<char*>(&code_error_filt_chips), sizeof(double));
d_dump_file.write(reinterpret_cast<char*>(&d_code_error_chips_Ti), sizeof(double));
d_dump_file.write(reinterpret_cast<char*>(&d_code_error_filt_chips_Ti), sizeof(double));
// CN0 and carrier lock test
d_dump_file.write(reinterpret_cast<char*>(&d_CN0_SNV_dB_Hz), sizeof(double));
d_dump_file.write(reinterpret_cast<char*>(&d_carrier_lock_test), sizeof(double));
// AUX vars (for debug purposes)
tmp_double = d_rem_code_phase_samples;
tmp_double = d_code_error_chips_Ti*CURRENT_INTEGRATION_TIME_S;
d_dump_file.write(reinterpret_cast<char*>(&tmp_double), sizeof(double));
tmp_double = static_cast<double>(d_sample_counter + d_correlation_length_samples);
d_dump_file.write(reinterpret_cast<char*>(&tmp_double), sizeof(double));

33
src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_pll_c_aid_tracking_cc.h
View File

@@ -39,13 +39,16 @@
#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"
#include "tracking_FLL_PLL_filter.h"
#include "tracking_loop_filter.h"
#include "cpu_multicorrelator.h"
class gps_l1_ca_dll_pll_c_aid_tracking_cc;
@@ -62,6 +65,9 @@ gps_l1_ca_dll_pll_c_aid_make_tracking_cc(long if_freq,
std::string dump_filename,
float pll_bw_hz,
float dll_bw_hz,
float pll_bw_narrow_hz,
float dll_bw_narrow_hz,
int extend_correlation_ms,
float early_late_space_chips);
@@ -94,6 +100,9 @@ private:
std::string dump_filename,
float pll_bw_hz,
float dll_bw_hz,
float pll_bw_narrow_hz,
float dll_bw_narrow_hz,
int extend_correlation_ms,
float early_late_space_chips);
gps_l1_ca_dll_pll_c_aid_tracking_cc(long if_freq,
@@ -104,6 +113,9 @@ private:
std::string dump_filename,
float pll_bw_hz,
float dll_bw_hz,
float pll_bw_narrow_hz,
float dll_bw_narrow_hz,
int extend_correlation_ms,
float early_late_space_chips);
// tracking configuration vars
@@ -130,8 +142,10 @@ 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;
Tracking_2nd_DLL_filter d_code_loop_filter;
Tracking_FLL_PLL_filter d_carrier_loop_filter;
@@ -140,6 +154,10 @@ private:
double d_acq_carrier_doppler_hz;
// tracking vars
float d_dll_bw_hz;
float d_pll_bw_hz;
float d_dll_bw_narrow_hz;
float d_pll_bw_narrow_hz;
double d_code_freq_chips;
double d_code_phase_step_chips;
double d_carrier_doppler_hz;
@@ -147,6 +165,21 @@ private:
double d_acc_carrier_phase_cycles;
double d_code_phase_samples;
double d_pll_to_dll_assist_secs_Ti;
double d_code_error_chips_Ti;
double d_code_error_filt_chips_s;
double d_code_error_filt_chips_Ti;
double d_carr_phase_error_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;
double d_preamble_timestamp_s;
int d_extend_correlation_ms;
bool d_enable_extended_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;

23
src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_pll_c_aid_tracking_sc.cc
View File

@@ -66,10 +66,12 @@ gps_l1_ca_dll_pll_c_aid_make_tracking_sc(
std::string dump_filename,
float pll_bw_hz,
float dll_bw_hz,
float pll_bw_narrow_hz,
float dll_bw_narrow_hz,
float early_late_space_chips)
{
return gps_l1_ca_dll_pll_c_aid_tracking_sc_sptr(new gps_l1_ca_dll_pll_c_aid_tracking_sc(if_freq,
fs_in, vector_length, queue, dump, dump_filename, pll_bw_hz, dll_bw_hz, early_late_space_chips));
fs_in, vector_length, queue, dump, dump_filename, pll_bw_hz, dll_bw_hz, pll_bw_narrow_hz, dll_bw_narrow_hz, early_late_space_chips));
}
@@ -94,10 +96,14 @@ gps_l1_ca_dll_pll_c_aid_tracking_sc::gps_l1_ca_dll_pll_c_aid_tracking_sc(
std::string dump_filename,
float pll_bw_hz,
float dll_bw_hz,
float pll_bw_narrow_hz,
float dll_bw_narrow_hz,
float early_late_space_chips) :
gr::block("gps_l1_ca_dll_pll_c_aid_tracking_sc", gr::io_signature::make(1, 1, sizeof(lv_16sc_t)),
gr::io_signature::make(1, 1, sizeof(Gnss_Synchro)))
{
// Telemetry bit synchronization message port input
this->message_port_register_in(pmt::mp("preamble_timestamp_s"));
// initialize internal vars
d_queue = queue;
d_dump = dump;
@@ -108,6 +114,10 @@ gps_l1_ca_dll_pll_c_aid_tracking_sc::gps_l1_ca_dll_pll_c_aid_tracking_sc(
d_correlation_length_samples = static_cast<int>(d_vector_length);
// Initialize tracking ==========================================
d_pll_bw_hz=pll_bw_hz;
d_dll_bw_hz=dll_bw_hz;
d_pll_bw_narrow_hz=pll_bw_narrow_hz;
d_dll_bw_narrow_hz=dll_bw_narrow_hz;
d_code_loop_filter.set_DLL_BW(dll_bw_hz);
d_carrier_loop_filter.set_params(10.0, pll_bw_hz,2);
@@ -330,17 +340,9 @@ int gps_l1_ca_dll_pll_c_aid_tracking_sc::general_work (int noutput_items, gr_vec
// ################# CARRIER WIPEOFF AND CORRELATORS ##############################
// perform carrier wipe-off and compute Early, Prompt and Late correlation
//volk_gnsssdr_32fc_convert_16ic(d_in_16sc,in,d_correlation_length_samples);
//std::cout << std::fixed << std::setw( 11 ) << std::setprecision( 6 );
//std::cout<<"in="<<in[0]<<std::endl;
multicorrelator_cpu_16sc.set_input_output_vectors(d_correlator_outs_16sc,in);
multicorrelator_cpu_16sc.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);
//std::cout<<"E 16sc="<<d_correlator_outs_16sc[0]<<std::endl;
//std::cout<<"P 16sc="<<d_correlator_outs_16sc[1]<<std::endl;
//std::cout<<"L 16sc="<<d_correlator_outs_16sc[2]<<std::endl;
//std::cout<<std::endl;
// UPDATE INTEGRATION TIME
CURRENT_INTEGRATION_TIME_S = static_cast<double>(d_correlation_length_samples) / static_cast<double>(d_fs_in);
@@ -450,6 +452,8 @@ int gps_l1_ca_dll_pll_c_aid_tracking_sc::general_work (int noutput_items, gr_vec
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;
current_synchro_data.correlation_length_ms=1;
*out[0] = current_synchro_data;
// ########## DEBUG OUTPUT
@@ -504,6 +508,7 @@ int gps_l1_ca_dll_pll_c_aid_tracking_sc::general_work (int noutput_items, gr_vec
current_synchro_data.System = {'G'};
current_synchro_data.Flag_valid_pseudorange = false;
current_synchro_data.Flag_valid_symbol_output = false;
*out[0] = current_synchro_data;
}

10
src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_pll_c_aid_tracking_sc.h
View File

@@ -67,6 +67,8 @@ gps_l1_ca_dll_pll_c_aid_make_tracking_sc(long if_freq,
std::string dump_filename,
float pll_bw_hz,
float dll_bw_hz,
float pll_bw_narrow_hz,
float dll_bw_narrow_hz,
float early_late_space_chips);
@@ -99,6 +101,8 @@ private:
std::string dump_filename,
float pll_bw_hz,
float dll_bw_hz,
float pll_bw_narrow_hz,
float dll_bw_narrow_hz,
float early_late_space_chips);
gps_l1_ca_dll_pll_c_aid_tracking_sc(long if_freq,
@@ -109,6 +113,8 @@ private:
std::string dump_filename,
float pll_bw_hz,
float dll_bw_hz,
float pll_bw_narrow_hz,
float dll_bw_narrow_hz,
float early_late_space_chips);
// tracking configuration vars
@@ -148,6 +154,10 @@ private:
double d_acq_carrier_doppler_hz;
// tracking vars
float d_dll_bw_hz;
float d_pll_bw_hz;
float d_dll_bw_narrow_hz;
float d_pll_bw_narrow_hz;
double d_code_freq_chips;
double d_code_phase_step_chips;
double d_carrier_doppler_hz;

19
src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_pll_tracking_cc.cc
View File

@@ -104,6 +104,8 @@ Gps_L1_Ca_Dll_Pll_Tracking_cc::Gps_L1_Ca_Dll_Pll_Tracking_cc(
gr::block("Gps_L1_Ca_Dll_Pll_Tracking_cc", gr::io_signature::make(1, 1, sizeof(gr_complex)),
gr::io_signature::make(1, 1, sizeof(Gnss_Synchro)))
{
// Telemetry bit synchronization message port input
this->message_port_register_in(pmt::mp("preamble_timestamp_s"));
// initialize internal vars
d_queue = queue;
d_dump = dump;
@@ -309,8 +311,6 @@ void Gps_L1_Ca_Dll_Pll_Tracking_cc::update_local_carrier()
d_carr_sign[i] = std::complex<float>(cos_f, -sin_f);
phase_rad_i += phase_step_rad_i;
}
//d_rem_carr_phase_rad = fmod(phase_rad, GPS_TWO_PI);
//d_acc_carrier_phase_rad = d_acc_carrier_phase_rad + d_rem_carr_phase_rad;
}
@@ -362,11 +362,8 @@ int Gps_L1_Ca_Dll_Pll_Tracking_cc::general_work (int noutput_items, gr_vector_in
acq_to_trk_delay_samples = d_sample_counter - d_acq_sample_stamp;
acq_trk_shif_correction_samples = d_current_prn_length_samples - fmod(static_cast<float>(acq_to_trk_delay_samples), static_cast<float>(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) / static_cast<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";
// Fill the acquisition data
current_synchro_data = *d_acquisition_gnss_synchro;
*out[0] = current_synchro_data;
@@ -493,11 +490,6 @@ int Gps_L1_Ca_Dll_Pll_Tracking_cc::general_work (int noutput_items, gr_vector_in
current_synchro_data.Prompt_I = static_cast<double>((*d_Prompt).real());
current_synchro_data.Prompt_Q = static_cast<double>((*d_Prompt).imag());
// Tracking_timestamp_secs is aligned with the NEXT PRN start sample (Hybridization problem!)
//compute remnant code phase samples BEFORE the Tracking timestamp
//d_rem_code_phase_samples = K_blk_samples - d_current_prn_length_samples; //rounding error < 1 sample
//current_synchro_data.Tracking_timestamp_secs = ((double)d_sample_counter + (double)d_current_prn_length_samples + (double)d_rem_code_phase_samples)/static_cast<double>(d_fs_in);
// Tracking_timestamp_secs is aligned with the CURRENT PRN start sample (Hybridization OK!, but some glitches??)
current_synchro_data.Tracking_timestamp_secs = (static_cast<double>(d_sample_counter) + static_cast<double>(d_rem_code_phase_samples)) / static_cast<double>(d_fs_in);
//compute remnant code phase samples AFTER the Tracking timestamp
@@ -510,6 +502,8 @@ int Gps_L1_Ca_Dll_Pll_Tracking_cc::general_work (int noutput_items, gr_vector_in
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;
current_synchro_data.correlation_length_ms=1;
*out[0] = current_synchro_data;
// ########## DEBUG OUTPUT
@@ -563,6 +557,7 @@ int Gps_L1_Ca_Dll_Pll_Tracking_cc::general_work (int noutput_items, gr_vector_in
current_synchro_data.System = {'G'};
current_synchro_data.Flag_valid_pseudorange = false;
current_synchro_data.Flag_valid_symbol_output = false;
*out[0] = current_synchro_data;
}
@@ -616,7 +611,7 @@ int Gps_L1_Ca_Dll_Pll_Tracking_cc::general_work (int noutput_items, gr_vector_in
tmp_double = static_cast<double>(d_sample_counter + d_current_prn_length_samples);
d_dump_file.write(reinterpret_cast<char*>(&tmp_double), sizeof(double));
}
catch (std::ifstream::failure e)
catch (const std::ifstream::failure &e)
{
LOG(WARNING) << "Exception writing trk dump file " << e.what();
}
@@ -651,7 +646,7 @@ void Gps_L1_Ca_Dll_Pll_Tracking_cc::set_channel(unsigned int channel)
d_dump_file.open(d_dump_filename.c_str(), std::ios::out | std::ios::binary);
LOG(INFO) << "Tracking dump enabled on channel " << d_channel << " Log file: " << d_dump_filename.c_str() << std::endl;
}
catch (std::ifstream::failure e)
catch (const std::ifstream::failure &e)
{
LOG(WARNING) << "channel " << d_channel << " Exception opening trk dump file " << e.what() << std::endl;
}

5
src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_pll_tracking_gpu_cc.cc
View File

@@ -99,6 +99,8 @@ Gps_L1_Ca_Dll_Pll_Tracking_GPU_cc::Gps_L1_Ca_Dll_Pll_Tracking_GPU_cc(
gr::block("Gps_L1_Ca_Dll_Pll_Tracking_GPU_cc", gr::io_signature::make(1, 1, sizeof(gr_complex)),
gr::io_signature::make(1, 1, sizeof(Gnss_Synchro)))
{
// Telemetry bit synchronization message port input
this->message_port_register_in(pmt::mp("preamble_timestamp_s"));
// initialize internal vars
d_queue = queue;
d_dump = dump;
@@ -451,6 +453,8 @@ int Gps_L1_Ca_Dll_Pll_Tracking_GPU_cc::general_work (int noutput_items, gr_vecto
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;
current_synchro_data.correlation_length_ms=1;
*out[0] = current_synchro_data;
// ########## DEBUG OUTPUT
@@ -505,6 +509,7 @@ int Gps_L1_Ca_Dll_Pll_Tracking_GPU_cc::general_work (int noutput_items, gr_vecto
current_synchro_data.System = {'G'};
current_synchro_data.Flag_valid_pseudorange = false;
current_synchro_data.Flag_valid_symbol_output = false;
*out[0] = current_synchro_data;
}

606
src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_pll_tracking_gpu_cc_old.cc
View File

@@ -1,606 +0,0 @@
/*!
* \file gps_l1_ca_dll_pll_tracking_gpu_cc.cc
* \brief Implementation of a code DLL + carrier PLL tracking block, GPU ACCELERATED
* \author Javier Arribas, 2015. 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
* Approach, Birkhauser, 2007
*
* -------------------------------------------------------------------------
*
* Copyright (C) 2010-2015 (see AUTHORS file for a list of contributors)
*
* 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
* (at your option) any later version.
*
* 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_dll_pll_tracking_gpu_cc.h"
#include <cmath>
#include <iostream>
#include <memory>
#include <sstream>
#include <boost/lexical_cast.hpp>
#include <gnuradio/io_signature.h>
#include <glog/logging.h>
#include "gnss_synchro.h"
#include "gps_sdr_signal_processing.h"
#include "tracking_discriminators.h"
#include "lock_detectors.h"
#include "GPS_L1_CA.h"
#include "control_message_factory.h"
#include <volk/volk.h> //volk_alignement
// includes
#include <cuda_profiler_api.h>
/*!
* \todo Include in definition header file
*/
#define CN0_ESTIMATION_SAMPLES 20
#define MINIMUM_VALID_CN0 25
#define MAXIMUM_LOCK_FAIL_COUNTER 50
#define CARRIER_LOCK_THRESHOLD 0.85
using google::LogMessage;
gps_l1_ca_dll_pll_tracking_gpu_cc_sptr
gps_l1_ca_dll_pll_make_tracking_gpu_cc(
long if_freq,
long fs_in,
unsigned int vector_length,
boost::shared_ptr<gr::msg_queue> queue,
bool dump,
std::string dump_filename,
float pll_bw_hz,
float dll_bw_hz,
float early_late_space_chips)
{
return gps_l1_ca_dll_pll_tracking_gpu_cc_sptr(new Gps_L1_Ca_Dll_Pll_Tracking_GPU_cc(if_freq,
fs_in, vector_length, queue, dump, dump_filename, pll_bw_hz, dll_bw_hz, early_late_space_chips));
}
void Gps_L1_Ca_Dll_Pll_Tracking_GPU_cc::forecast (int noutput_items,
gr_vector_int &ninput_items_required)
{
ninput_items_required[0] = static_cast<int>(d_vector_length) * 2; //set the required available samples in each call
}
Gps_L1_Ca_Dll_Pll_Tracking_GPU_cc::Gps_L1_Ca_Dll_Pll_Tracking_GPU_cc(
long if_freq,
long fs_in,
unsigned int vector_length,
boost::shared_ptr<gr::msg_queue> queue,
bool dump,
std::string dump_filename,
float pll_bw_hz,
float dll_bw_hz,
float early_late_space_chips) :
gr::block("Gps_L1_Ca_Dll_Pll_Tracking_GPU_cc", gr::io_signature::make(1, 1, sizeof(gr_complex)),
gr::io_signature::make(1, 1, sizeof(Gnss_Synchro)))
{
// initialize internal vars
d_queue = queue;
d_dump = dump;
d_if_freq = if_freq;
d_fs_in = fs_in;
d_vector_length = vector_length;
d_dump_filename = dump_filename;
// Initialize tracking ==========================================
d_code_loop_filter.set_DLL_BW(dll_bw_hz);
d_carrier_loop_filter.set_PLL_BW(pll_bw_hz);
//--- DLL variables --------------------------------------------------------
d_early_late_spc_chips = early_late_space_chips; // Define early-late offset (in chips)
// Set GPU flags
cudaSetDeviceFlags(cudaDeviceMapHost);
//allocate host memory
//pinned memory mode - use special function to get OS-pinned memory
int N_CORRELATORS = 3;
// Get space for a vector with the C/A code replica sampled 1x/chip
cudaHostAlloc((void**)&d_ca_code, (GPS_L1_CA_CODE_LENGTH_CHIPS* sizeof(gr_complex)), cudaHostAllocMapped || cudaHostAllocWriteCombined);
// Get space for the resampled early / prompt / late local replicas
cudaHostAlloc((void**)&d_local_code_shift_chips, N_CORRELATORS * sizeof(float), cudaHostAllocMapped || cudaHostAllocWriteCombined);
cudaHostAlloc((void**)&in_gpu, 2 * d_vector_length * sizeof(gr_complex), cudaHostAllocMapped || cudaHostAllocWriteCombined);
// correlator outputs (scalar)
cudaHostAlloc((void**)&d_corr_outs_gpu ,sizeof(gr_complex)*N_CORRELATORS, cudaHostAllocMapped || cudaHostAllocWriteCombined );
//map to EPL pointers
d_Early = &d_corr_outs_gpu[0];
d_Prompt = &d_corr_outs_gpu[1];
d_Late = &d_corr_outs_gpu[2];
//--- Perform initializations ------------------------------
multicorrelator_gpu = new cuda_multicorrelator();
//local code resampler on GPU
multicorrelator_gpu->init_cuda_integrated_resampler(2 * d_vector_length, GPS_L1_CA_CODE_LENGTH_CHIPS, 3);
multicorrelator_gpu->set_input_output_vectors(d_corr_outs_gpu, in_gpu);
// define initial code frequency basis of NCO
d_code_freq_chips = 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;
d_last_seg = 0;
d_current_prn_length_samples = static_cast<int>(d_vector_length);
// CN0 estimation and lock detector buffers
d_cn0_estimation_counter = 0;
d_Prompt_buffer = new gr_complex[CN0_ESTIMATION_SAMPLES];
d_carrier_lock_test = 1;
d_CN0_SNV_dB_Hz = 0;
d_carrier_lock_fail_counter = 0;
d_carrier_lock_threshold = CARRIER_LOCK_THRESHOLD;
systemName["G"] = std::string("GPS");
systemName["S"] = std::string("SBAS");
set_relative_rate(1.0/((double)d_vector_length*2));
d_channel_internal_queue = 0;
d_acquisition_gnss_synchro = 0;
d_channel = 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 = 0.0;
d_acc_code_phase_secs = 0.0;
//set_min_output_buffer((long int)300);
}
void Gps_L1_Ca_Dll_Pll_Tracking_GPU_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;
d_acq_sample_stamp = d_acquisition_gnss_synchro->Acq_samplestamp_samples;
long int acq_trk_diff_samples;
double acq_trk_diff_seconds;
acq_trk_diff_samples = static_cast<long int>(d_sample_counter) - static_cast<long int>(d_acq_sample_stamp);//-d_vector_length;
DLOG(INFO) << "Number of samples between Acquisition and Tracking =" << acq_trk_diff_samples;
acq_trk_diff_seconds = static_cast<double>(acq_trk_diff_samples) / static_cast<double>(d_fs_in);
//doppler effect
// Fd=(C/(C+Vr))*F
double 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
double T_chip_mod_seconds;
double T_prn_mod_seconds;
double T_prn_mod_samples;
d_code_freq_chips = radial_velocity * GPS_L1_CA_CODE_RATE_HZ;
T_chip_mod_seconds = 1.0/d_code_freq_chips;
T_prn_mod_seconds = T_chip_mod_seconds * GPS_L1_CA_CODE_LENGTH_CHIPS;
T_prn_mod_samples = T_prn_mod_seconds * static_cast<double>(d_fs_in);
d_current_prn_length_samples = round(T_prn_mod_samples);
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 * static_cast<double>(d_fs_in);
double T_prn_diff_seconds= T_prn_true_seconds - T_prn_mod_seconds;
double N_prn_diff = acq_trk_diff_seconds / T_prn_true_seconds;
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 * static_cast<double>(d_fs_in)), T_prn_true_samples);
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;
// DLL/PLL filter initialization
d_carrier_loop_filter.initialize(); // initialize the carrier filter
d_code_loop_filter.initialize(); // initialize the code filter
// generate local reference ALWAYS starting at chip 1 (1 sample per chip)
gps_l1_ca_code_gen_complex(d_ca_code, d_acquisition_gnss_synchro->PRN, 0);
d_local_code_shift_chips[0] = - d_early_late_spc_chips;
d_local_code_shift_chips[1] = 0.0;
d_local_code_shift_chips[2] = d_early_late_spc_chips;
multicorrelator_gpu->set_local_code_and_taps(GPS_L1_CA_CODE_LENGTH_CHIPS, d_ca_code, d_local_code_shift_chips, 3);
d_carrier_lock_fail_counter = 0;
d_rem_code_phase_samples = 0;
d_rem_carr_phase_rad = 0;
d_acc_carrier_phase_rad = 0;
d_acc_code_phase_secs = 0;
d_code_phase_samples = d_acq_code_phase_samples;
std::string sys_ = &d_acquisition_gnss_synchro->System;
sys = sys_.substr(0,1);
// DEBUG OUTPUT
std::cout << "Tracking start on channel " << d_channel << " for satellite " << Gnss_Satellite(systemName[sys], d_acquisition_gnss_synchro->PRN) << std::endl;
LOG(INFO) << "Starting tracking of satellite " << Gnss_Satellite(systemName[sys], d_acquisition_gnss_synchro->PRN) << " on channel " << d_channel;
// enable tracking
d_pull_in = true;
d_enable_tracking = true;
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;
}
Gps_L1_Ca_Dll_Pll_Tracking_GPU_cc::~Gps_L1_Ca_Dll_Pll_Tracking_GPU_cc()
{
d_dump_file.close();
cudaFreeHost(in_gpu);
cudaFreeHost(d_corr_outs_gpu);
cudaFreeHost(d_local_code_shift_chips);
cudaFreeHost(d_ca_code);
multicorrelator_gpu->free_cuda();
delete(multicorrelator_gpu);
delete[] d_Prompt_buffer;
}
int Gps_L1_Ca_Dll_Pll_Tracking_GPU_cc::general_work (int noutput_items, gr_vector_int &ninput_items,
gr_vector_const_void_star &input_items, gr_vector_void_star &output_items)
{
// process vars
double carr_error_hz=0.0;
double carr_error_filt_hz=0.0;
double code_error_chips=0.0;
double code_error_filt_chips=0.0;
// Block input data and block output stream pointers
const gr_complex* in = (gr_complex*) input_items[0];
Gnss_Synchro **out = (Gnss_Synchro **) &output_items[0];
// GNSS_SYNCHRO OBJECT to interchange data between tracking->telemetry_decoder
Gnss_Synchro current_synchro_data = Gnss_Synchro();
if (d_enable_tracking == true)
{
// Receiver signal alignment
if (d_pull_in == true)
{
int samples_offset;
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_current_prn_length_samples - fmod(static_cast<float>(acq_to_trk_delay_samples), static_cast<float>(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) / static_cast<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";
// Fill the acquisition data
current_synchro_data = *d_acquisition_gnss_synchro;
*out[0] = current_synchro_data;
consume_each(samples_offset); //shift input to perform alignment with local replica
return 1;
}
// Fill the acquisition data
current_synchro_data = *d_acquisition_gnss_synchro;
// UPDATE NCO COMMAND
double phase_step_rad = GPS_TWO_PI * d_carrier_doppler_hz / static_cast<double>(d_fs_in);
//code resampler on GPU (new)
double code_phase_step_chips = d_code_freq_chips / static_cast<double>(d_fs_in);
double rem_code_phase_chips = d_rem_code_phase_samples * (d_code_freq_chips / d_fs_in);
std::cout<<"rem_code_phase_chips="<<rem_code_phase_chips<<" d_current_prn_length_samples="<<d_current_prn_length_samples<<std::endl;
memcpy(in_gpu, in, sizeof(gr_complex) * d_current_prn_length_samples);
cudaProfilerStart();
multicorrelator_gpu->Carrier_wipeoff_multicorrelator_resampler_cuda( static_cast<float>(d_rem_carr_phase_rad),
static_cast<float>(phase_step_rad),
static_cast<float>(code_phase_step_chips),
static_cast<float>(rem_code_phase_chips),
d_current_prn_length_samples, 3);
cudaProfilerStop();
// ################## PLL ##########################################################
// PLL discriminator
carr_error_hz = pll_cloop_two_quadrant_atan(*d_Prompt) / GPS_TWO_PI;
// Carrier discriminator filter
carr_error_filt_hz = d_carrier_loop_filter.get_carrier_nco(carr_error_hz);
// New carrier Doppler frequency estimation
d_carrier_doppler_hz = d_acq_carrier_doppler_hz + carr_error_filt_hz;
// New code Doppler frequency estimation
d_code_freq_chips = GPS_L1_CA_CODE_RATE_HZ + ((d_carrier_doppler_hz * GPS_L1_CA_CODE_RATE_HZ) / GPS_L1_FREQ_HZ);
//carrier phase accumulator for (K) doppler estimation
d_acc_carrier_phase_rad -= GPS_TWO_PI * d_carrier_doppler_hz * GPS_L1_CA_CODE_PERIOD;
//remanent carrier phase to prevent overflow in the code NCO
d_rem_carr_phase_rad = d_rem_carr_phase_rad + GPS_TWO_PI * d_carrier_doppler_hz * GPS_L1_CA_CODE_PERIOD;
d_rem_carr_phase_rad = fmod(d_rem_carr_phase_rad, GPS_TWO_PI);
// ################## DLL ##########################################################
// DLL discriminator
code_error_chips = dll_nc_e_minus_l_normalized(*d_Early, *d_Late); //[chips/Ti]
// Code discriminator filter
code_error_filt_chips = d_code_loop_filter.get_code_nco(code_error_chips); //[chips/second]
//Code phase accumulator
double code_error_filt_secs;
code_error_filt_secs = (GPS_L1_CA_CODE_PERIOD * code_error_filt_chips) / GPS_L1_CA_CODE_RATE_HZ; //[seconds]
d_acc_code_phase_secs = d_acc_code_phase_secs + code_error_filt_secs;
// ################## 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 / static_cast<double>(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 + code_error_filt_secs * static_cast<double>(d_fs_in);
d_current_prn_length_samples = round(K_blk_samples); //round to a discrete samples
//d_rem_code_phase_samples = K_blk_samples - d_current_prn_length_samples; //rounding error < 1 sample
// ####### 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_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_Prompt).real());
current_synchro_data.Prompt_Q = static_cast<double>((*d_Prompt).imag());
// Tracking_timestamp_secs is aligned with the NEXT PRN start sample (Hybridization problem!)
//compute remnant code phase samples BEFORE the Tracking timestamp
//d_rem_code_phase_samples = K_blk_samples - d_current_prn_length_samples; //rounding error < 1 sample
//current_synchro_data.Tracking_timestamp_secs = ((double)d_sample_counter + (double)d_current_prn_length_samples + (double)d_rem_code_phase_samples)/static_cast<double>(d_fs_in);
// Tracking_timestamp_secs is aligned with the CURRENT PRN start sample (Hybridization OK!, but some glitches??)
current_synchro_data.Tracking_timestamp_secs = (static_cast<double>(d_sample_counter) + d_rem_code_phase_samples) / static_cast<double>(d_fs_in);
//compute remnant code phase samples AFTER the Tracking timestamp
d_rem_code_phase_samples = K_blk_samples - d_current_prn_length_samples; //rounding error < 1 sample
//current_synchro_data.Tracking_timestamp_secs = ((double)d_sample_counter)/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 = d_acc_carrier_phase_rad;
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;
// ########## DEBUG OUTPUT
/*!
* \todo The stop timer has to be moved to the signal source!
*/
// debug: Second counter in channel 0
if (d_channel == 0)
{
if (floor(d_sample_counter / d_fs_in) != d_last_seg)
{
d_last_seg = floor(d_sample_counter / d_fs_in);
std::cout << "Current input signal time = " << d_last_seg << " [s]" << std::endl;
DLOG(INFO) << "GPS L1 C/A Tracking CH " << d_channel << ": Satellite " << Gnss_Satellite(systemName[sys], d_acquisition_gnss_synchro->PRN)
<< ", CN0 = " << d_CN0_SNV_dB_Hz << " [dB-Hz]" << std::endl;
//if (d_last_seg==5) d_carrier_lock_fail_counter=500; //DEBUG: force unlock!
}
}
else
{
if (floor(d_sample_counter / d_fs_in) != d_last_seg)
{
d_last_seg = floor(d_sample_counter / d_fs_in);
DLOG(INFO) << "Tracking CH " << d_channel << ": Satellite " << Gnss_Satellite(systemName[sys], d_acquisition_gnss_synchro->PRN)
<< ", CN0 = " << d_CN0_SNV_dB_Hz << " [dB-Hz]";
}
}
}
else
{
// ########## DEBUG OUTPUT (TIME ONLY for channel 0 when tracking is disabled)
/*!
* \todo The stop timer has to be moved to the signal source!
*/
// stream to collect cout calls to improve thread safety
std::stringstream tmp_str_stream;
if (floor(d_sample_counter / d_fs_in) != d_last_seg)
{
d_last_seg = floor(d_sample_counter / d_fs_in);
if (d_channel == 0)
{
// debug: Second counter in channel 0
tmp_str_stream << "Current input signal time = " << d_last_seg << " [s]" << std::endl << std::flush;
std::cout << tmp_str_stream.rdbuf() << std::flush;
}
}
*d_Early = gr_complex(0,0);
*d_Prompt = gr_complex(0,0);
*d_Late = gr_complex(0,0);
current_synchro_data.System = {'G'};
current_synchro_data.Flag_valid_pseudorange = false;
*out[0] = current_synchro_data;
}
if(d_dump)
{
// MULTIPLEXED FILE RECORDING - Record results to file
float prompt_I;
float prompt_Q;
float tmp_E, tmp_P, tmp_L;
float tmp_float;
double tmp_double;
prompt_I = (*d_Prompt).real();
prompt_Q = (*d_Prompt).imag();
tmp_E = std::abs<float>(*d_Early);
tmp_P = std::abs<float>(*d_Prompt);
tmp_L = std::abs<float>(*d_Late);
try
{
// EPR
d_dump_file.write((char*)&tmp_E, sizeof(float));
d_dump_file.write((char*)&tmp_P, sizeof(float));
d_dump_file.write((char*)&tmp_L, sizeof(float));
// PROMPT I and Q (to analyze navigation symbols)
d_dump_file.write((char*)&prompt_I, sizeof(float));
d_dump_file.write((char*)&prompt_Q, sizeof(float));
// PRN start sample stamp
//tmp_float=(float)d_sample_counter;
d_dump_file.write((char*)&d_sample_counter, sizeof(unsigned long int));
// accumulated carrier phase
tmp_float = d_acc_carrier_phase_rad;
d_dump_file.write((char*)&tmp_float, sizeof(float));
// carrier and code frequency
tmp_float = d_carrier_doppler_hz;
d_dump_file.write((char*)&tmp_float, sizeof(float));
tmp_float = d_code_freq_chips;
d_dump_file.write((char*)&tmp_float, sizeof(float));
//PLL commands
tmp_float = carr_error_hz;
d_dump_file.write((char*)&tmp_float, sizeof(float));
tmp_float = carr_error_filt_hz;
d_dump_file.write((char*)&tmp_float, sizeof(float));
//DLL commands
tmp_float = code_error_chips;
d_dump_file.write((char*)&tmp_float, sizeof(float));
tmp_float = code_error_filt_chips;
d_dump_file.write((char*)&tmp_float, sizeof(float));
// CN0 and carrier lock test
tmp_float = d_CN0_SNV_dB_Hz;
d_dump_file.write((char*)&tmp_float, sizeof(float));
tmp_float = d_carrier_lock_test;
d_dump_file.write((char*)&tmp_float, sizeof(float));
// AUX vars (for debug purposes)
tmp_float = d_rem_code_phase_samples;
d_dump_file.write((char*)&tmp_float, sizeof(float));
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)
{
LOG(WARNING) << "Exception writing trk dump file " << e.what();
}
}
consume_each(d_current_prn_length_samples); // this is necessary in gr::block derivates
d_sample_counter += d_current_prn_length_samples; //count for the processed samples
//LOG(INFO)<<"GPS tracking output end on CH="<<this->d_channel << " SAMPLE STAMP="<<d_sample_counter<<std::endl;
return 1; //output tracking result ALWAYS even in the case of d_enable_tracking==false
}
void Gps_L1_Ca_Dll_Pll_Tracking_GPU_cc::set_channel(unsigned int channel)
{
d_channel = channel;
LOG(INFO) << "Tracking Channel set to " << d_channel;
// ############# ENABLE DATA FILE LOG #################
if (d_dump == true)
{
if (d_dump_file.is_open() == false)
{
try
{
d_dump_filename.append(boost::lexical_cast<std::string>(d_channel));
d_dump_filename.append(".dat");
d_dump_file.exceptions (std::ifstream::failbit | std::ifstream::badbit);
d_dump_file.open(d_dump_filename.c_str(), std::ios::out | std::ios::binary);
LOG(INFO) << "Tracking dump enabled on channel " << d_channel << " Log file: " << d_dump_filename.c_str() << std::endl;
}
catch (std::ifstream::failure e)
{
LOG(WARNING) << "channel " << d_channel << " Exception opening trk dump file " << e.what() << std::endl;
}
}
}
}
void Gps_L1_Ca_Dll_Pll_Tracking_GPU_cc::set_channel_queue(concurrent_queue<int> *channel_internal_queue)
{
d_channel_internal_queue = channel_internal_queue;
}
void Gps_L1_Ca_Dll_Pll_Tracking_GPU_cc::set_gnss_synchro(Gnss_Synchro* p_gnss_synchro)
{
d_acquisition_gnss_synchro = p_gnss_synchro;
}

6
src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_tcp_connector_tracking_cc.cc
View File

@@ -106,6 +106,8 @@ Gps_L1_Ca_Tcp_Connector_Tracking_cc::Gps_L1_Ca_Tcp_Connector_Tracking_cc(
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)))
{
// Telemetry bit synchronization message port input
this->message_port_register_in(pmt::mp("preamble_timestamp_s"));
// initialize internal vars
d_queue = queue;
d_dump = dump;
@@ -434,7 +436,7 @@ int Gps_L1_Ca_Tcp_Connector_Tracking_cc::general_work (int noutput_items, gr_vec
current_synchro_data.CN0_dB_hz = 0.0;
current_synchro_data.Flag_valid_tracking = false;
current_synchro_data.Flag_valid_pseudorange = false;
current_synchro_data.Flag_valid_symbol_output = true;
*out[0] = current_synchro_data;
return 1;
@@ -547,6 +549,8 @@ int Gps_L1_Ca_Tcp_Connector_Tracking_cc::general_work (int noutput_items, gr_vec
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;
current_synchro_data.Flag_valid_pseudorange = false;
current_synchro_data.Flag_valid_symbol_output = true;
current_synchro_data.correlation_length_ms=1;
*out[0] = current_synchro_data;
// ########## DEBUG OUTPUT

15
src/algorithms/tracking/gnuradio_blocks/gps_l2_m_dll_pll_tracking_cc.cc
View File

@@ -102,7 +102,8 @@ gps_l2_m_dll_pll_tracking_cc::gps_l2_m_dll_pll_tracking_cc(
float early_late_space_chips) :
gr::block("gps_l2_m_dll_pll_tracking_cc", gr::io_signature::make(1, 1, sizeof(gr_complex)),
gr::io_signature::make(1, 1, sizeof(Gnss_Synchro)))
{
{ // Telemetry bit synchronization message port input
this->message_port_register_in(pmt::mp("preamble_timestamp_s"));
// initialize internal vars
d_queue = queue;
d_dump = dump;
@@ -311,8 +312,6 @@ void gps_l2_m_dll_pll_tracking_cc::update_local_carrier()
d_carr_sign[i] = gr_complex(cos(phase_rad), -sin(phase_rad));
phase_rad += phase_step_rad;
}
//d_rem_carr_phase_rad = fmod(phase_rad, GPS_L2_TWO_PI);
//d_acc_carrier_phase_rad = d_acc_carrier_phase_rad + d_rem_carr_phase_rad;
}
@@ -414,7 +413,7 @@ int gps_l2_m_dll_pll_tracking_cc::general_work (int noutput_items, gr_vector_int
current_synchro_data.CN0_dB_hz = 0.0;
current_synchro_data.Flag_valid_tracking = false;
current_synchro_data.Flag_valid_pseudorange = false;
current_synchro_data.Flag_valid_symbol_output = false;
*out[0] = current_synchro_data;
return 1;
@@ -499,11 +498,6 @@ int gps_l2_m_dll_pll_tracking_cc::general_work (int noutput_items, gr_vector_int
current_synchro_data.Prompt_I = static_cast<double>((*d_Prompt).real());
current_synchro_data.Prompt_Q = static_cast<double>((*d_Prompt).imag());
// Tracking_timestamp_secs is aligned with the NEXT PRN start sample (Hybridization problem!)
//compute remnant code phase samples BEFORE the Tracking timestamp
//d_rem_code_phase_samples = K_blk_samples - d_current_prn_length_samples; //rounding error < 1 sample
//current_synchro_data.Tracking_timestamp_secs = ((double)d_sample_counter + (double)d_current_prn_length_samples + (double)d_rem_code_phase_samples)/static_cast<double>(d_fs_in);
// Tracking_timestamp_secs is aligned with the CURRENT PRN start sample (Hybridization OK!, but some glitches??)
current_synchro_data.Tracking_timestamp_secs = (static_cast<double>(d_sample_counter) + d_rem_code_phase_samples) / static_cast<double>(d_fs_in);
//compute remnant code phase samples AFTER the Tracking timestamp
@@ -516,6 +510,8 @@ int gps_l2_m_dll_pll_tracking_cc::general_work (int noutput_items, gr_vector_int
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_tracking = true;
current_synchro_data.Flag_valid_symbol_output = true;
current_synchro_data.correlation_length_ms=1;
*out[0] = current_synchro_data;
// ########## DEBUG OUTPUT
@@ -570,6 +566,7 @@ int gps_l2_m_dll_pll_tracking_cc::general_work (int noutput_items, gr_vector_int
*d_Late = gr_complex(0,0);
current_synchro_data.Flag_valid_pseudorange = false;
current_synchro_data.Flag_valid_symbol_output = false;
*out[0] = current_synchro_data;
}

28
src/algorithms/tracking/libs/cpu_multicorrelator.cc
View File

@@ -100,21 +100,23 @@ bool cpu_multicorrelator::set_input_output_vectors(std::complex<float>* corr_out
return true;
}
void cpu_multicorrelator::update_local_code(int correlator_length_samples, float rem_code_phase_chips, float code_phase_step_chips)
void cpu_multicorrelator::update_local_code(int correlator_length_samples,float rem_code_phase_chips, float code_phase_step_chips)
{
float local_code_chip_index;
int local_code_chip_index;
for (int current_correlator_tap = 0; current_correlator_tap < d_n_correlators; current_correlator_tap++)
{
for (int n = 0; n < correlator_length_samples; n++)
{
// resample code for current tap
local_code_chip_index = std::fmod(code_phase_step_chips * static_cast<float>(n) + d_shifts_chips[current_correlator_tap] - rem_code_phase_chips, d_code_length_chips);
//Take into account that in multitap correlators, the shifts can be negative!
if (local_code_chip_index < 0.0) local_code_chip_index += d_code_length_chips;
d_local_codes_resampled[current_correlator_tap][n] = d_local_code_in[static_cast<int>(round(local_code_chip_index))];
}
}
{
for (int n = 0; n < correlator_length_samples; n++)
{
// resample code for current tap
local_code_chip_index = floor(code_phase_step_chips*static_cast<float>(n) + d_shifts_chips[current_correlator_tap]- rem_code_phase_chips);
local_code_chip_index = local_code_chip_index % d_code_length_chips;
//Take into account that in multitap correlators, the shifts can be negative!
if (local_code_chip_index < 0) local_code_chip_index += d_code_length_chips;
d_local_codes_resampled[current_correlator_tap][n] = d_local_code_in[local_code_chip_index];
}
}
}

21
src/algorithms/tracking/libs/lock_detectors.cc
View File

@@ -67,21 +67,22 @@
*/
float cn0_svn_estimator(gr_complex* Prompt_buffer, int length, long fs_in, double code_length)
{
float SNR = 0;
float SNR_dB_Hz = 0;
float Psig = 0;
float Ptot = 0;
double SNR = 0;
double SNR_dB_Hz = 0;
double Psig = 0;
double Ptot = 0;
for (int i=0; i<length; i++)
{
Psig += std::abs(Prompt_buffer[i].real());
Ptot += Prompt_buffer[i].imag() * Prompt_buffer[i].imag() + Prompt_buffer[i].real() * Prompt_buffer[i].real();
Psig += std::abs(static_cast<double>(Prompt_buffer[i].real()));
Ptot += static_cast<double>(Prompt_buffer[i].imag()) * static_cast<double>(Prompt_buffer[i].imag())
+ static_cast<double>(Prompt_buffer[i].real()) * static_cast<double>(Prompt_buffer[i].real());
}
Psig = Psig / (float)length;
Psig = Psig / static_cast<double>(length);
Psig = Psig * Psig;
Ptot = Ptot / (float)length;
Ptot = Ptot / static_cast<double>(length);
SNR = Psig / (Ptot - Psig);
SNR_dB_Hz = 10 * log10(SNR) + 10 * log10(fs_in/2) - 10 * log10((float)code_length);
return SNR_dB_Hz;
SNR_dB_Hz = 10 * log10(SNR) + 10 * log10(static_cast<double>(fs_in)/2) - 10 * log10(code_length);
return static_cast<float>(SNR_dB_Hz);
}