Minor changes

This commit is contained in:
Antonio Ramos 2018-03-12 15:16:39 +01:00
parent 026f2eea84
commit 74e8af01f9
11 changed files with 777 additions and 741 deletions

View File

@ -37,8 +37,8 @@
#include "dll_pll_veml_tracking.h"
#include <cmath>
#include <iostream>
#include <memory>
#include <sstream>
#include <algorithm>
#include <boost/lexical_cast.hpp>
#include <gnuradio/io_signature.h>
#include <glog/logging.h>
@ -95,7 +95,10 @@ dll_pll_veml_tracking_sptr dll_pll_veml_make_tracking(
void dll_pll_veml_tracking::forecast(int noutput_items,
gr_vector_int &ninput_items_required)
{
if (noutput_items != 0) { ninput_items_required[0] = static_cast<int>(d_vector_length) * 2; }
if (noutput_items != 0)
{
ninput_items_required[0] = static_cast<int>(d_vector_length) * 2;
}
}
@ -105,8 +108,7 @@ dll_pll_veml_tracking::dll_pll_veml_tracking(
float pll_bw_narrow_hz, float dll_bw_narrow_hz,
float early_late_space_chips, float very_early_late_space_chips,
float early_late_space_narrow_chips, float very_early_late_space_narrow_chips,
int extend_correlation_symbols, bool track_pilot, char system, char signal[3], bool veml):
gr::block("dll_pll_veml_tracking", gr::io_signature::make(1, 1, sizeof(gr_complex)),
int extend_correlation_symbols, bool track_pilot, char system, char signal[3], bool veml) : gr::block("dll_pll_veml_tracking", gr::io_signature::make(1, 1, sizeof(gr_complex)),
gr::io_signature::make(1, 1, sizeof(Gnss_Synchro)))
{
// Telemetry bit synchronization message port input
@ -117,6 +119,7 @@ dll_pll_veml_tracking::dll_pll_veml_tracking(
// initialize internal vars
d_dump = dump;
d_veml = veml;
d_track_pilot = track_pilot;
d_fs_in = fs_in;
d_vector_length = vector_length;
d_dump_filename = dump_filename;
@ -124,33 +127,42 @@ dll_pll_veml_tracking::dll_pll_veml_tracking(
d_code_chip_rate = 0.0;
d_signal_carrier_freq = 0.0;
d_code_length_chips = 0;
if((system - 'G') == 0)
d_secondary = false;
d_secondary_code_length = 0;
d_secondary_code_string = nullptr;
d_correlation_length_ms = 0;
signal_type = std::string(signal);
if (system == 'G')
{
systemName["G"] = std::string("GPS");
sys = "G";
if(std::string(signal).compare("1C") == 0)
systemName = "GPS";
if (signal_type.compare("1C") == 0)
{
d_signal_carrier_freq = GPS_L1_FREQ_HZ;
d_code_period = GPS_L1_CA_CODE_PERIOD;
d_code_chip_rate = GPS_L1_CA_CODE_RATE_HZ;
d_correlation_length_ms = 1;
d_code_length_chips = static_cast<unsigned int>(GPS_L1_CA_CODE_LENGTH_CHIPS);
d_secondary = false;
d_track_pilot = false;
}
else if(std::string(signal).compare("2S") == 0)
else if (signal_type.compare("2S") == 0)
{
d_signal_carrier_freq = GPS_L2_FREQ_HZ;
d_code_period = GPS_L2_M_PERIOD;
d_code_chip_rate = GPS_L2_M_CODE_RATE_HZ;
d_code_length_chips = static_cast<unsigned int>(GPS_L2_M_CODE_LENGTH_CHIPS);
d_correlation_length_ms = 20;
d_secondary = false;
d_track_pilot = false;
}
else if(std::string(signal).compare("L5") == 0)
else if (signal_type.compare("L5") == 0)
{
d_signal_carrier_freq = GPS_L5_FREQ_HZ;
d_code_period = GPS_L5i_PERIOD;
d_code_chip_rate = GPS_L5i_CODE_RATE_HZ;
d_correlation_length_ms = 1;
d_code_length_chips = static_cast<unsigned int>(GPS_L5i_CODE_LENGTH_CHIPS);
d_secondary = false;
}
else
{
@ -158,23 +170,44 @@ dll_pll_veml_tracking::dll_pll_veml_tracking(
std::cout << "Invalid Signal argument when instantiating tracking blocks" << std::endl;
}
}
else if((system - 'E') == 0)
else if (system == 'E')
{
systemName["E"] = std::string("Galileo");
sys = "E";
if(std::string(signal).compare("1B") == 0)
systemName = "Galileo";
if (signal_type.compare("1B") == 0)
{
d_signal_carrier_freq = Galileo_E1_FREQ_HZ;
d_code_period = Galileo_E1_CODE_PERIOD;
d_code_chip_rate = Galileo_E1_CODE_CHIP_RATE_HZ;
d_code_length_chips = static_cast<unsigned int>(Galileo_E1_B_CODE_LENGTH_CHIPS);
d_correlation_length_ms = 4;
d_secondary = true;
if (d_track_pilot)
{
d_secondary_code_length = static_cast<unsigned int>(Galileo_E1_C_SECONDARY_CODE_LENGTH);
d_secondary_code_string = const_cast<std::string *>(&Galileo_E1_C_SECONDARY_CODE);
}
else if(std::string(signal).compare("5X") == 0)
else
{
d_secondary = false;
}
}
else if (signal_type.compare("5X") == 0)
{
d_signal_carrier_freq = Galileo_E5a_FREQ_HZ;
d_code_period = GALILEO_E5a_CODE_PERIOD;
d_code_chip_rate = Galileo_E5a_CODE_CHIP_RATE_HZ;
d_correlation_length_ms = 1;
d_code_length_chips = static_cast<unsigned int>(Galileo_E5a_CODE_LENGTH_CHIPS);
d_secondary = true;
if (d_track_pilot)
{
d_secondary_code_length = static_cast<unsigned int>(Galileo_E5a_Q_SECONDARY_CODE_LENGTH);
}
else
{
d_secondary_code_length = static_cast<unsigned int>(Galileo_E5a_I_SECONDARY_CODE_LENGTH);
d_secondary_code_string = const_cast<std::string *>(&Galileo_E5a_I_SECONDARY_CODE);
}
}
else
{
@ -189,7 +222,6 @@ dll_pll_veml_tracking::dll_pll_veml_tracking(
}
d_code_loop_filter = Tracking_2nd_DLL_filter(d_code_period);
d_carrier_loop_filter = Tracking_2nd_PLL_filter(d_code_period);
@ -215,16 +247,21 @@ dll_pll_veml_tracking::dll_pll_veml_tracking(
d_tracking_code = static_cast<float *>(volk_gnsssdr_malloc(2 * d_code_length_chips * sizeof(float), volk_gnsssdr_get_alignment()));
// correlator outputs (scalar)
if(d_veml) { d_n_correlator_taps = 5; } // Very-Early, Early, Prompt, Late, Very-Late
else { d_n_correlator_taps = 3; }
if (d_veml)
{
// Very-Early, Early, Prompt, Late, Very-Late
d_n_correlator_taps = 5;
}
else
{
// Early, Prompt, Late
d_n_correlator_taps = 3;
}
d_correlator_outs = static_cast<gr_complex *>(volk_gnsssdr_malloc(d_n_correlator_taps * sizeof(gr_complex), volk_gnsssdr_get_alignment()));
d_local_code_shift_chips = static_cast<float *>(volk_gnsssdr_malloc(d_n_correlator_taps * sizeof(float), volk_gnsssdr_get_alignment()));
std::fill_n(d_correlator_outs, d_n_correlator_taps, gr_complex(0.0, 0.0));
for (int n = 0; n < d_n_correlator_taps; n++)
{
d_correlator_outs[n] = gr_complex(0,0);
}
// map memory pointers of correlator outputs
if (d_veml)
{
@ -238,7 +275,7 @@ dll_pll_veml_tracking::dll_pll_veml_tracking(
d_local_code_shift_chips[2] = 0.0;
d_local_code_shift_chips[3] = d_early_late_spc_chips;
d_local_code_shift_chips[4] = d_very_early_late_spc_chips;
d_null_shift = &d_local_code_shift_chips[2];
}
else
{
@ -250,6 +287,7 @@ dll_pll_veml_tracking::dll_pll_veml_tracking(
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;
d_null_shift = &d_local_code_shift_chips[1];
}
d_correlation_length_samples = d_vector_length;
@ -257,7 +295,6 @@ dll_pll_veml_tracking::dll_pll_veml_tracking(
d_extend_correlation_symbols = extend_correlation_symbols;
// Enable Data component prompt correlator (slave to Pilot prompt) if tracking uses Pilot signal
d_track_pilot = track_pilot;
if (d_track_pilot)
{
// extended integration control
@ -270,11 +307,9 @@ dll_pll_veml_tracking::dll_pll_veml_tracking(
d_enable_extended_integration = false;
}
// Extra correlator for the data component
d_local_code_data_shift_chips = static_cast<float*>(volk_gnsssdr_malloc(sizeof(float), volk_gnsssdr_get_alignment()));
d_local_code_data_shift_chips[0] = 0.0;
correlator_data_cpu.init(2 * d_correlation_length_samples, 1);
d_Prompt_Data = static_cast<gr_complex *>(volk_gnsssdr_malloc(sizeof(gr_complex), volk_gnsssdr_get_alignment()));
d_Prompt_Data[0] = gr_complex(0,0);
d_Prompt_Data[0] = gr_complex(0.0, 0.0);
d_data_code = static_cast<float *>(volk_gnsssdr_malloc(2 * d_code_length_chips * sizeof(float), volk_gnsssdr_get_alignment()));
}
else
@ -283,7 +318,7 @@ dll_pll_veml_tracking::dll_pll_veml_tracking(
d_enable_extended_integration = false;
}
//--- Initializations ------------------------------
//--- Initializations ---//
// Initial code frequency basis of NCO
d_code_freq_chips = d_code_chip_rate;
// Residual code phase (in chips)
@ -293,7 +328,6 @@ dll_pll_veml_tracking::dll_pll_veml_tracking(
// sample synchronization
d_sample_counter = 0;
//d_sample_counter_seconds = 0;
d_acq_sample_stamp = 0;
d_current_prn_length_samples = static_cast<int>(d_vector_length);
@ -358,7 +392,7 @@ void dll_pll_veml_tracking::start_tracking()
double 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 < 0.0)
{
corrected_acq_phase_samples = T_prn_mod_samples + corrected_acq_phase_samples;
corrected_acq_phase_samples += T_prn_mod_samples;
}
double delay_correction_samples = d_acq_code_phase_samples - corrected_acq_phase_samples;
@ -378,8 +412,8 @@ void dll_pll_veml_tracking::start_tracking()
d_acquisition_gnss_synchro->PRN, Galileo_E1_CODE_CHIP_RATE_HZ, 0);
galileo_e1_code_gen_float_sampled(d_data_code, d_acquisition_gnss_synchro->Signal, false,
d_acquisition_gnss_synchro->PRN, Galileo_E1_CODE_CHIP_RATE_HZ, 0);
d_Prompt_Data[0] = gr_complex(0,0);
correlator_data_cpu.set_local_code_and_taps(d_code_length_chips, d_data_code, d_local_code_shift_chips);
d_Prompt_Data[0] = gr_complex(0.0, 0.0);
correlator_data_cpu.set_local_code_and_taps(d_code_length_chips, d_data_code, d_null_shift);
}
else
{
@ -388,10 +422,7 @@ void dll_pll_veml_tracking::start_tracking()
}
multicorrelator_cpu.set_local_code_and_taps(d_code_length_chips, d_tracking_code, d_local_code_shift_chips);
for (int n = 0; n < d_n_correlator_taps; n++)
{
d_correlator_outs[n] = gr_complex(0,0);
}
std::fill_n(d_correlator_outs, d_n_correlator_taps, gr_complex(0.0, 0.0));
d_carrier_lock_fail_counter = 0;
d_rem_code_phase_samples = 0.0;
@ -402,8 +433,8 @@ void dll_pll_veml_tracking::start_tracking()
d_code_phase_samples = d_acq_code_phase_samples;
// DEBUG OUTPUT
std::cout << "Tracking of Galileo E1 signal started 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;
std::cout << "Tracking of " << systemName << " " << signal_type << " signal started on channel " << d_channel << " for satellite " << Gnss_Satellite(systemName, d_acquisition_gnss_synchro->PRN) << std::endl;
LOG(INFO) << "Starting tracking of satellite " << Gnss_Satellite(systemName, d_acquisition_gnss_synchro->PRN) << " on channel " << d_channel;
// enable tracking pull-in
d_state = 1;
@ -448,7 +479,6 @@ dll_pll_veml_tracking::~dll_pll_veml_tracking()
{
volk_gnsssdr_free(d_Prompt_Data);
volk_gnsssdr_free(d_data_code);
volk_gnsssdr_free(d_local_code_data_shift_chips);
correlator_data_cpu.free();
}
delete[] d_Prompt_buffer;
@ -465,11 +495,11 @@ bool dll_pll_veml_tracking::acquire_secondary()
{
//******* preamble correlation ********
int corr_value = 0;
for (unsigned int i = 0; i < Galileo_E1_C_SECONDARY_CODE_LENGTH; i++)
for (unsigned int i = 0; i < d_secondary_code_length; i++)
{
if (d_Prompt_buffer_deque.at(i).real() < 0) // symbols clipping
if (d_Prompt_buffer_deque.at(i).real() < 0.0) // symbols clipping
{
if (Galileo_E1_C_SECONDARY_CODE.at(i) == '0')
if (d_secondary_code_string->at(i) == '0')
{
corr_value++;
}
@ -480,7 +510,7 @@ bool dll_pll_veml_tracking::acquire_secondary()
}
else
{
if (Galileo_E1_C_SECONDARY_CODE.at(i) == '0')
if (d_secondary_code_string->at(i) == '0')
{
corr_value--;
}
@ -491,7 +521,7 @@ bool dll_pll_veml_tracking::acquire_secondary()
}
}
if (abs(corr_value) == Galileo_E1_C_SECONDARY_CODE_LENGTH)
if (abs(corr_value) == d_secondary_code_length)
{
return true;
}
@ -516,7 +546,7 @@ bool dll_pll_veml_tracking::cn0_and_tracking_lock_status()
{
d_cn0_estimation_counter = 0;
// Code lock indicator
d_CN0_SNV_dB_Hz = cn0_svn_estimator(d_Prompt_buffer, DLL_PLL_CN0_ESTIMATION_SAMPLES, d_fs_in, Galileo_E1_B_CODE_LENGTH_CHIPS);
d_CN0_SNV_dB_Hz = cn0_svn_estimator(d_Prompt_buffer, DLL_PLL_CN0_ESTIMATION_SAMPLES, d_fs_in, static_cast<double>(d_code_length_chips));
// Carrier lock indicator
d_carrier_lock_test = carrier_lock_detector(d_Prompt_buffer, DLL_PLL_CN0_ESTIMATION_SAMPLES);
// Loss of lock detection
@ -595,7 +625,7 @@ void dll_pll_veml_tracking::run_dll_pll(bool disable_costas_loop)
// New carrier Doppler frequency estimation
d_carrier_doppler_hz = d_acq_carrier_doppler_hz + d_carr_error_filt_hz;
// New code Doppler frequency estimation
d_code_freq_chips = Galileo_E1_CODE_CHIP_RATE_HZ + ((d_carrier_doppler_hz * Galileo_E1_CODE_CHIP_RATE_HZ) / Galileo_E1_FREQ_HZ);
d_code_freq_chips = (1.0 + d_carrier_doppler_hz / d_signal_carrier_freq) * d_code_chip_rate;
// ################## DLL ##########################################################
// DLL discriminator
@ -607,11 +637,14 @@ void dll_pll_veml_tracking::run_dll_pll(bool disable_costas_loop)
void dll_pll_veml_tracking::clear_tracking_vars()
{
*d_Very_Early = gr_complex(0,0);
*d_Early = gr_complex(0,0);
*d_Prompt = gr_complex(0,0);
*d_Late = gr_complex(0,0);
*d_Very_Late= gr_complex(0,0);
if (d_veml)
{
*d_Very_Early = gr_complex(0.0, 0.0);
*d_Very_Late = gr_complex(0.0, 0.0);
}
*d_Early = gr_complex(0.0, 0.0);
*d_Prompt = gr_complex(0.0, 0.0);
*d_Late = gr_complex(0.0, 0.0);
d_carr_error_hz = 0.0;
d_carr_error_filt_hz = 0.0;
d_code_error_chips = 0.0;
@ -634,11 +667,19 @@ void dll_pll_veml_tracking::log_data()
prompt_I = static_cast<double>(d_P_accu.real());
prompt_Q = static_cast<double>(d_P_accu.imag());
if (d_veml)
{
tmp_VE = std::abs<float>(d_VE_accu);
tmp_VL = std::abs<float>(d_VL_accu);
}
else
{
tmp_VE = 0.0;
tmp_VL = 0.0;
}
tmp_E = std::abs<float>(d_E_accu);
tmp_P = std::abs<float>(d_P_accu);
tmp_L = std::abs<float>(d_L_accu);
tmp_VL = std::abs<float>(d_VL_accu);
try
{
@ -697,87 +738,77 @@ int dll_pll_veml_tracking::general_work (int noutput_items __attribute__((unused
gr_vector_const_void_star &input_items, gr_vector_void_star &output_items)
{
gr::thread::scoped_lock l(d_setlock);
// Block input data and block output stream pointers
const gr_complex *in = reinterpret_cast<const gr_complex *>(input_items[0]);
Gnss_Synchro **out = reinterpret_cast<Gnss_Synchro **>(&output_items[0]);
// GNSS_SYNCHRO OBJECT to interchange data between tracking->telemetry_decoder
Gnss_Synchro current_synchro_data = Gnss_Synchro();
switch (d_state)
{
case 0: // standby - bypass
case 0: // Standby - Pass Through
{
current_synchro_data.Tracking_sample_counter = d_sample_counter;
break;
}
case 1: // pull-in
case 1: // Pull-in
{
/*
* Signal alignment (skip samples until the incoming signal is aligned with local replica)
*/
// Signal alignment (skip samples until the incoming signal is aligned with local replica)
// Fill the acquisition data
current_synchro_data = *d_acquisition_gnss_synchro;
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 - std::fmod(static_cast<double>(acq_to_trk_delay_samples), static_cast<double>(d_current_prn_length_samples));
samples_offset = round(d_acq_code_phase_samples + acq_trk_shif_correction_samples);
current_synchro_data.Tracking_sample_counter = d_sample_counter;
current_synchro_data.fs = d_fs_in;
*out[0] = current_synchro_data;
d_sample_counter = d_sample_counter + samples_offset; // count for the processed samples
int acq_to_trk_delay_samples = d_sample_counter - d_acq_sample_stamp;
double acq_trk_shif_correction_samples = d_current_prn_length_samples - std::fmod(static_cast<double>(acq_to_trk_delay_samples), static_cast<double>(d_current_prn_length_samples));
int samples_offset = round(d_acq_code_phase_samples + acq_trk_shif_correction_samples);
d_sample_counter += samples_offset; // count for the processed samples
consume_each(samples_offset); // shift input to perform alignment with local replica
d_state = 2; // next state is the symbol synchronization
return 0;
}
case 2: // wide tracking and symbol synchronization
case 2: // Wide tracking and symbol synchronization
{
// Fill the acquisition data
current_synchro_data = *d_acquisition_gnss_synchro;
// Current NCO and code generator parameters
d_carrier_phase_step_rad = GALILEO_TWO_PI * d_carrier_doppler_hz / static_cast<double>(d_fs_in);
d_code_phase_step_chips = d_code_freq_chips / static_cast<double>(d_fs_in);
d_rem_code_phase_chips = d_rem_code_phase_samples * d_code_freq_chips / d_fs_in;
// perform a correlation step
d_carrier_phase_step_rad = GALILEO_TWO_PI * d_carrier_doppler_hz / d_fs_in;
d_code_phase_step_chips = d_code_freq_chips / d_fs_in;
d_rem_code_phase_chips = d_rem_code_phase_samples * d_code_phase_step_chips;
// Perform a correlation step
do_correlation_step(in);
// save single correlation step variables
// Save single correlation step variables
if (d_veml)
{
d_VE_accu = *d_Very_Early;
d_VL_accu = *d_Very_Late;
}
d_E_accu = *d_Early;
d_P_accu = *d_Prompt;
d_L_accu = *d_Late;
d_VL_accu = *d_Very_Late;
// check lock status
if (cn0_and_tracking_lock_status() == false)
// Check lock status
if (!cn0_and_tracking_lock_status())
{
clear_tracking_vars();
d_state = 0; // loss-of-lock detected
}
else
{
// perform DLL/PLL tracking loop computations
// Perform DLL/PLL tracking loop computations
run_dll_pll(false);
// ################## PLL COMMANDS #################################################
// carrier phase accumulator for (K) Doppler estimation-
d_acc_carrier_phase_rad -= GALILEO_TWO_PI * d_carrier_doppler_hz * static_cast<double>(d_current_prn_length_samples) / static_cast<double>(d_fs_in);
// remnant carrier phase to prevent overflow in the code NCO
d_rem_carr_phase_rad = d_rem_carr_phase_rad + GALILEO_TWO_PI * d_carrier_doppler_hz * static_cast<double>(d_current_prn_length_samples) / static_cast<double>(d_fs_in);
d_acc_carrier_phase_rad -= GALILEO_TWO_PI * d_carrier_doppler_hz * static_cast<double>(d_current_prn_length_samples) / d_fs_in;
// remanent carrier phase to prevent overflow in the code NCO
d_rem_carr_phase_rad = d_rem_carr_phase_rad + GALILEO_TWO_PI * d_carrier_doppler_hz * static_cast<double>(d_current_prn_length_samples) / d_fs_in;
d_rem_carr_phase_rad = std::fmod(d_rem_carr_phase_rad, GALILEO_TWO_PI);
// ################## DLL COMMANDS #################################################
// Code error from DLL
double code_error_filt_secs;
code_error_filt_secs = (Galileo_E1_CODE_PERIOD * d_code_error_filt_chips) / Galileo_E1_CODE_CHIP_RATE_HZ; // [seconds]
double code_error_filt_secs = d_code_period * d_code_error_filt_chips / d_code_chip_rate; // [seconds]
// ################## CARRIER AND CODE NCO BUFFER ALIGNEMENT #######################
// keep alignment parameters for the next input buffer
// Compute the next buffer length based in the new period of the PRN sequence and the code phase error estimation
double T_chip_seconds = 1.0 / d_code_freq_chips;
double T_prn_seconds = T_chip_seconds * Galileo_E1_B_CODE_LENGTH_CHIPS;
double T_prn_samples = T_prn_seconds * static_cast<double>(d_fs_in);
double K_blk_samples = T_prn_samples + d_rem_code_phase_samples + code_error_filt_secs * static_cast<double>(d_fs_in);
double T_prn_seconds = T_chip_seconds * static_cast<double>(d_code_length_chips);
double T_prn_samples = T_prn_seconds * d_fs_in;
double K_blk_samples = T_prn_samples + d_rem_code_phase_samples + code_error_filt_secs * d_fs_in;
d_current_prn_length_samples = round(K_blk_samples); // round to a discrete number of samples
// ########### Output the tracking results to Telemetry block ##########
@ -791,7 +822,6 @@ int dll_pll_veml_tracking::general_work (int noutput_items __attribute__((unused
current_synchro_data.Prompt_I = static_cast<double>((*d_Prompt).real());
current_synchro_data.Prompt_Q = static_cast<double>((*d_Prompt).imag());
}
current_synchro_data.Tracking_sample_counter = d_sample_counter;
current_synchro_data.Code_phase_samples = d_rem_code_phase_samples;
// 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
@ -799,50 +829,53 @@ int dll_pll_veml_tracking::general_work (int noutput_items __attribute__((unused
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_symbol_output = true;
current_synchro_data.correlation_length_ms = Galileo_E1_CODE_PERIOD_MS;
current_synchro_data.correlation_length_ms = d_correlation_length_ms;
// enable write dump file this cycle (valid DLL/PLL cycle)
log_data();
//std::cout<<(d_Prompt->real()>0);
if (d_enable_extended_integration)
{
// ####### SECONDARY CODE LOCK #####
d_Prompt_buffer_deque.push_back(*d_Prompt);
if (d_Prompt_buffer_deque.size() == Galileo_E1_C_SECONDARY_CODE_LENGTH)
if (d_Prompt_buffer_deque.size() == d_secondary_code_length)
{
if (acquire_secondary() == true)
if (acquire_secondary())
{
d_extend_correlation_symbols_count = 0;
// reset extended correlator
d_VE_accu = gr_complex(0,0);
d_E_accu = gr_complex(0,0);
d_P_accu = gr_complex(0,0);
d_L_accu = gr_complex(0,0);
d_VL_accu = gr_complex(0,0);
d_VE_accu = gr_complex(0.0, 0.0);
d_E_accu = gr_complex(0.0, 0.0);
d_P_accu = gr_complex(0.0, 0.0);
d_L_accu = gr_complex(0.0, 0.0);
d_VL_accu = gr_complex(0.0, 0.0);
d_Prompt_buffer_deque.clear();
d_current_symbol = 0;
d_code_loop_filter.set_DLL_BW(d_dll_bw_narrow_hz);
d_carrier_loop_filter.set_PLL_BW(d_pll_bw_narrow_hz);
// Set TAPs delay values [chips]
// Set narrow taps delay values [chips]
if (d_veml)
{
d_local_code_shift_chips[0] = -d_very_early_late_spc_narrow_chips;
d_local_code_shift_chips[1] = -d_early_late_spc_narrow_chips;
d_local_code_shift_chips[2] = 0.0;
d_local_code_shift_chips[3] = d_early_late_spc_narrow_chips;
d_local_code_shift_chips[4] = d_very_early_late_spc_narrow_chips;
}
else
{
d_local_code_shift_chips[0] = -d_early_late_spc_narrow_chips;
d_local_code_shift_chips[2] = d_early_late_spc_narrow_chips;
}
LOG(INFO) << "Enabled " << d_extend_correlation_symbols << " [symbols] extended correlator for CH "
<< d_channel
<< " : Satellite " << Gnss_Satellite(systemName[sys], d_acquisition_gnss_synchro->PRN);
<< " : Satellite " << Gnss_Satellite(systemName, d_acquisition_gnss_synchro->PRN);
std::cout << "Enabled " << d_extend_correlation_symbols << " [symbols] extended correlator for CH "
<< d_channel
<< " : Satellite " << Gnss_Satellite(systemName[sys], d_acquisition_gnss_synchro->PRN) << std::endl;
//std::cout << " pll_bw = " << d_pll_bw_hz << " [Hz], pll_narrow_bw = " << d_pll_bw_narrow_hz << " [Hz]" << std::endl;
//std::cout << " dll_bw = " << d_dll_bw_hz << " [Hz], dll_narrow_bw = " << d_dll_bw_narrow_hz << " [Hz]" << std::endl;
<< " : Satellite " << Gnss_Satellite(systemName, d_acquisition_gnss_synchro->PRN) << std::endl;
// UPDATE INTEGRATION TIME
double new_correlation_time_s = static_cast<double>(d_extend_correlation_symbols) * Galileo_E1_CODE_PERIOD;
float new_correlation_time_s = static_cast<float>(d_extend_correlation_symbols) * static_cast<float>(d_code_period);
d_carrier_loop_filter.set_pdi(new_correlation_time_s);
d_code_loop_filter.set_pdi(new_correlation_time_s);
@ -860,31 +893,37 @@ int dll_pll_veml_tracking::general_work (int noutput_items __attribute__((unused
// Fill the acquisition data
current_synchro_data = *d_acquisition_gnss_synchro;
// Current NCO and code generator parameters
d_carrier_phase_step_rad = GALILEO_TWO_PI * d_carrier_doppler_hz / static_cast<double>(d_fs_in);
d_code_phase_step_chips = d_code_freq_chips / static_cast<double>(d_fs_in);
d_carrier_phase_step_rad = GALILEO_TWO_PI * d_carrier_doppler_hz / d_fs_in;
d_code_phase_step_chips = d_code_freq_chips / d_fs_in;
d_rem_code_phase_chips = d_rem_code_phase_samples * d_code_freq_chips / d_fs_in;
// perform a correlation step
do_correlation_step(in);
// correct the integration sign using the current symbol of the secondary code
if (Galileo_E1_C_SECONDARY_CODE.at(d_current_symbol) == '0')
if (d_secondary_code_string->at(d_current_symbol) == '0')
{
if (d_veml)
{
d_VE_accu += *d_Very_Early;
d_VL_accu += *d_Very_Late;
}
d_E_accu += *d_Early;
d_P_accu += *d_Prompt;
d_L_accu += *d_Late;
d_VL_accu += *d_Very_Late;
}
else
{
if (d_veml)
{
d_VE_accu -= *d_Very_Early;
d_VL_accu -= *d_Very_Late;
}
d_E_accu -= *d_Early;
d_P_accu -= *d_Prompt;
d_L_accu -= *d_Late;
d_VL_accu -= *d_Very_Late;
}
d_current_symbol++;
// secondary code roll-up
d_current_symbol = d_current_symbol % Galileo_E1_C_SECONDARY_CODE_LENGTH;
d_current_symbol %= d_secondary_code_length;
// PLL/DLL not enabled, we are in the middle of a coherent integration
// keep alignment parameters for the next input buffer
@ -892,32 +931,31 @@ int dll_pll_veml_tracking::general_work (int noutput_items __attribute__((unused
// ################## PLL ##########################################################
// carrier phase accumulator for (K) Doppler estimation-
d_acc_carrier_phase_rad -= GALILEO_TWO_PI * d_carrier_doppler_hz * static_cast<double>(d_current_prn_length_samples) / static_cast<double>(d_fs_in);
d_acc_carrier_phase_rad -= GALILEO_TWO_PI * d_carrier_doppler_hz * static_cast<double>(d_current_prn_length_samples) / d_fs_in;
// remnant carrier phase to prevent overflow in the code NCO
d_rem_carr_phase_rad = d_rem_carr_phase_rad + GALILEO_TWO_PI * d_carrier_doppler_hz * static_cast<double>(d_current_prn_length_samples) / static_cast<double>(d_fs_in);
d_rem_carr_phase_rad = d_rem_carr_phase_rad + GALILEO_TWO_PI * d_carrier_doppler_hz * static_cast<double>(d_current_prn_length_samples) / d_fs_in;
d_rem_carr_phase_rad = std::fmod(d_rem_carr_phase_rad, GALILEO_TWO_PI);
// ################## CARRIER AND CODE NCO BUFFER ALIGNEMENT #######################
// keep alignment parameters for the next input buffer
// Compute the next buffer length based in the new period of the PRN sequence and the code phase error estimation
double T_chip_seconds = 1.0 / d_code_freq_chips;
double T_prn_seconds = T_chip_seconds * Galileo_E1_B_CODE_LENGTH_CHIPS;
double T_prn_samples = T_prn_seconds * static_cast<double>(d_fs_in);
double T_prn_seconds = T_chip_seconds * static_cast<double>(d_code_length_chips);
double T_prn_samples = T_prn_seconds * d_fs_in;
double K_blk_samples = T_prn_samples + d_rem_code_phase_samples;
d_current_prn_length_samples = round(K_blk_samples); //round to a discrete samples
d_current_prn_length_samples = static_cast<int>(round(K_blk_samples)); //round to a discrete samples
// ########### Output the tracking results to Telemetry block ##########
current_synchro_data.Prompt_I = static_cast<double>((*d_Prompt_Data).real());
current_synchro_data.Prompt_Q = static_cast<double>((*d_Prompt_Data).imag());
current_synchro_data.Tracking_sample_counter = d_sample_counter;
current_synchro_data.Code_phase_samples = d_rem_code_phase_samples;
// 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
d_rem_code_phase_samples = K_blk_samples - static_cast<double>(d_current_prn_length_samples); //rounding error < 1 sample
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_symbol_output = true;
current_synchro_data.correlation_length_ms = Galileo_E1_CODE_PERIOD_MS;
current_synchro_data.correlation_length_ms = d_correlation_length_ms;
d_extend_correlation_symbols_count++;
if (d_extend_correlation_symbols_count >= (d_extend_correlation_symbols - 1))
@ -935,28 +973,34 @@ int dll_pll_veml_tracking::general_work (int noutput_items __attribute__((unused
do_correlation_step(in);
// correct the integration using the current symbol
if (Galileo_E1_C_SECONDARY_CODE.at(d_current_symbol) == '0')
if (d_secondary_code_string->at(d_current_symbol) == '0')
{
if (d_veml)
{
d_VE_accu += *d_Very_Early;
d_VL_accu += *d_Very_Late;
}
d_E_accu += *d_Early;
d_P_accu += *d_Prompt;
d_L_accu += *d_Late;
d_VL_accu += *d_Very_Late;
}
else
{
if (d_veml)
{
d_VE_accu -= *d_Very_Early;
d_VL_accu -= *d_Very_Late;
}
d_E_accu -= *d_Early;
d_P_accu -= *d_Prompt;
d_L_accu -= *d_Late;
d_VL_accu -= *d_Very_Late;
}
d_current_symbol++;
// secondary code roll-up
d_current_symbol = d_current_symbol % Galileo_E1_C_SECONDARY_CODE_LENGTH;
d_current_symbol %= d_secondary_code_length;
// check lock status
if (cn0_and_tracking_lock_status() == false)
if (!cn0_and_tracking_lock_status())
{
clear_tracking_vars();
d_state = 0; // loss-of-lock detected
@ -967,45 +1011,43 @@ int dll_pll_veml_tracking::general_work (int noutput_items __attribute__((unused
// ################## PLL ##########################################################
// carrier phase accumulator for (K) Doppler estimation-
d_acc_carrier_phase_rad -= GALILEO_TWO_PI * d_carrier_doppler_hz * static_cast<double>(d_current_prn_length_samples) / static_cast<double>(d_fs_in);
d_acc_carrier_phase_rad -= GALILEO_TWO_PI * d_carrier_doppler_hz * static_cast<double>(d_current_prn_length_samples) / d_fs_in;
// remnant carrier phase to prevent overflow in the code NCO
d_rem_carr_phase_rad = d_rem_carr_phase_rad + GALILEO_TWO_PI * d_carrier_doppler_hz * static_cast<double>(d_current_prn_length_samples) / static_cast<double>(d_fs_in);
d_rem_carr_phase_rad = d_rem_carr_phase_rad + GALILEO_TWO_PI * d_carrier_doppler_hz * static_cast<double>(d_current_prn_length_samples) / d_fs_in;
d_rem_carr_phase_rad = std::fmod(d_rem_carr_phase_rad, GALILEO_TWO_PI);
// ################## DLL ##########################################################
// Code phase accumulator
double code_error_filt_secs;
code_error_filt_secs = (Galileo_E1_CODE_PERIOD * d_code_error_filt_chips) / Galileo_E1_CODE_CHIP_RATE_HZ; //[seconds]
double code_error_filt_secs = d_code_period * d_code_error_filt_chips / d_code_chip_rate; //[seconds]
// ################## CARRIER AND CODE NCO BUFFER ALIGNEMENT #######################
// keep alignment parameters for the next input buffer
// Compute the next buffer length based in the new period of the PRN sequence and the code phase error estimation
double T_chip_seconds = 1.0 / d_code_freq_chips;
double T_prn_seconds = T_chip_seconds * Galileo_E1_B_CODE_LENGTH_CHIPS;
double T_prn_samples = T_prn_seconds * static_cast<double>(d_fs_in);
double 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 number of samples
double T_prn_seconds = T_chip_seconds * static_cast<double>(d_code_length_chips);
double T_prn_samples = T_prn_seconds * d_fs_in;
double K_blk_samples = T_prn_samples + d_rem_code_phase_samples + code_error_filt_secs * d_fs_in;
d_current_prn_length_samples = static_cast<int>(round(K_blk_samples)); // round to a discrete number of samples
// ########### Output the tracking results to Telemetry block ##########
current_synchro_data.Prompt_I = static_cast<double>((*d_Prompt_Data).real());
current_synchro_data.Prompt_Q = static_cast<double>((*d_Prompt_Data).imag());
current_synchro_data.Tracking_sample_counter = d_sample_counter;
current_synchro_data.Code_phase_samples = d_rem_code_phase_samples;
// 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
d_rem_code_phase_samples = K_blk_samples - static_cast<double>(d_current_prn_length_samples); //rounding error < 1 sample
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_symbol_output = true;
current_synchro_data.correlation_length_ms = Galileo_E1_CODE_PERIOD_MS;
current_synchro_data.correlation_length_ms = d_correlation_length_ms;
// enable write dump file this cycle (valid DLL/PLL cycle)
log_data();
// reset extended correlator
d_VE_accu = gr_complex(0,0);
d_E_accu = gr_complex(0,0);
d_P_accu = gr_complex(0,0);
d_L_accu = gr_complex(0,0);
d_VL_accu = gr_complex(0,0);
d_VE_accu = gr_complex(0.0, 0.0);
d_E_accu = gr_complex(0.0, 0.0);
d_P_accu = gr_complex(0.0, 0.0);
d_L_accu = gr_complex(0.0, 0.0);
d_VL_accu = gr_complex(0.0, 0.0);
d_state = 3; //new coherent integration (correlation time extension) cycle
}
}
@ -1017,14 +1059,14 @@ int dll_pll_veml_tracking::general_work (int noutput_items __attribute__((unused
// const char * str = str_aux.c_str(); // get a C style null terminated string
// std::memcpy(static_cast<void*>(current_synchro_data.Signal), str, 3);
current_synchro_data.fs = d_fs_in;
*out[0] = current_synchro_data;
consume_each(d_current_prn_length_samples); // this is required for gr_block derivates
d_sample_counter += d_current_prn_length_samples; // count for the processed samples
consume_each(d_current_prn_length_samples);
d_sample_counter += d_current_prn_length_samples;
if (current_synchro_data.Flag_valid_symbol_output)
{
current_synchro_data.fs = static_cast<long int>(d_fs_in);
current_synchro_data.Tracking_sample_counter = d_sample_counter;
*out[0] = current_synchro_data;
return 1;
}
else
@ -1260,13 +1302,12 @@ int dll_pll_veml_tracking::save_matfile()
void dll_pll_veml_tracking::set_channel(unsigned int channel)
{
gr::thread::scoped_lock l(d_setlock);
d_channel = channel;
LOG(INFO) << "Tracking Channel set to " << d_channel;
// ############# ENABLE DATA FILE LOG #################
if (d_dump == true)
if (d_dump)
{
if (d_dump_file.is_open() == false)
if (!d_dump_file.is_open())
{
try
{
@ -1288,6 +1329,5 @@ void dll_pll_veml_tracking::set_channel(unsigned int channel)
void dll_pll_veml_tracking::set_gnss_synchro(Gnss_Synchro *p_gnss_synchro)
{
gr::thread::scoped_lock l(d_setlock);
d_acquisition_gnss_synchro = p_gnss_synchro;
}

View File

@ -39,7 +39,6 @@
#include <fstream>
#include <string>
#include <map>
#include <gnuradio/block.h>
#include "gnss_synchro.h"
#include "tracking_2nd_DLL_filter.h"
@ -83,6 +82,7 @@ public:
gr_vector_const_void_star &input_items, gr_vector_void_star &output_items);
void forecast(int noutput_items, gr_vector_int &ninput_items_required);
private:
friend dll_pll_veml_tracking_sptr dll_pll_veml_make_tracking(double fs_in, unsigned int vector_length,
bool dump, std::string dump_filename,
@ -93,8 +93,7 @@ private:
int extend_correlation_symbols, bool track_pilot,
char system, char signal[3], bool veml);
dll_pll_veml_tracking(double fs_in, unsigned
int vector_length,
dll_pll_veml_tracking(double fs_in, unsigned int vector_length,
bool dump,
std::string dump_filename,
float pll_bw_hz,
@ -121,10 +120,13 @@ private:
void log_data();
// tracking configuration vars
unsigned int d_vector_length;
bool d_dump;
bool d_veml;
bool d_secondary;
unsigned int d_secondary_code_length;
std::string *d_secondary_code_string;
Gnss_Synchro *d_acquisition_gnss_synchro;
unsigned int d_vector_length;
unsigned int d_channel;
// long d_fs_in;
double d_fs_in;
@ -141,23 +143,23 @@ private:
//Integration period in samples
int d_correlation_length_samples;
int d_correlation_length_ms;
int d_n_correlator_taps;
double d_early_late_spc_chips;
double d_very_early_late_spc_chips;
double d_early_late_spc_narrow_chips;
double d_very_early_late_spc_narrow_chips;
float *d_tracking_code;
float *d_data_code;
float *d_local_code_shift_chips;
float *d_null_shift;
gr_complex *d_correlator_outs;
cpu_multicorrelator_real_codes multicorrelator_cpu;
//todo: currently the multicorrelator does not support adding extra correlator
//TODO: currently the multicorrelator does not support adding extra correlator
//with different local code, thus we need extra multicorrelator instance.
//Implement this functionality inside multicorrelator class
//as an enhancement to increase the performance
float* d_local_code_data_shift_chips;
cpu_multicorrelator_real_codes correlator_data_cpu; //for data channel
gr_complex *d_Very_Early;
@ -166,9 +168,9 @@ private:
gr_complex *d_Late;
gr_complex *d_Very_Late;
bool d_enable_extended_integration;
int d_extend_correlation_symbols;
int d_extend_correlation_symbols_count;
bool d_enable_extended_integration;
int d_current_symbol;
gr_complex d_VE_accu;
@ -233,8 +235,8 @@ private:
std::string d_dump_filename;
std::ofstream d_dump_file;
std::map<std::string, std::string> systemName;
std::string sys;
std::string systemName;
std::string signal_type;
int save_matfile();
};

View File

@ -122,7 +122,7 @@ bool cpu_multicorrelator_real_codes::Carrier_wipeoff_multicorrelator_resampler(
lv_32fc_t phase_offset_as_complex[1];
phase_offset_as_complex[0] = lv_cmake(std::cos(rem_carrier_phase_in_rad), -std::sin(rem_carrier_phase_in_rad));
// call VOLK_GNSSSDR kernel
volk_gnsssdr_32fc_32f_rotator_dot_prod_32fc_xn(d_corr_out, d_sig_in, std::exp(lv_32fc_t(0, -phase_step_rad)), phase_offset_as_complex, (const float**)d_local_codes_resampled, d_n_correlators, signal_length_samples);
volk_gnsssdr_32fc_32f_rotator_dot_prod_32fc_xn(d_corr_out, d_sig_in, std::exp(lv_32fc_t(0.0, -phase_step_rad)), phase_offset_as_complex, (const float**)d_local_codes_resampled, d_n_correlators, signal_length_samples);
return true;
}

View File

@ -67,20 +67,20 @@
*/
float cn0_svn_estimator(gr_complex* Prompt_buffer, int length, long fs_in, double code_length)
{
double SNR = 0;
double SNR_dB_Hz = 0;
double Psig = 0;
double Ptot = 0;
double SNR = 0.0;
double SNR_dB_Hz = 0.0;
double Psig = 0.0;
double Ptot = 0.0;
for (int i = 0; i < length; i++)
{
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 / static_cast<double>(length);
Psig /= static_cast<double>(length);
Psig = Psig * Psig;
Ptot = Ptot / static_cast<double>(length);
Ptot /= static_cast<double>(length);
SNR = Psig / (Ptot - Psig);
SNR_dB_Hz = 10 * log10(SNR) + 10 * log10(static_cast<double>(fs_in) / 2) - 10 * log10(code_length);
SNR_dB_Hz = 10.0 * log10(SNR) + 10.0 * log10(static_cast<double>(fs_in) / 2.0) - 10.0 * log10(code_length);
return static_cast<float>(SNR_dB_Hz);
}
@ -96,10 +96,10 @@ float cn0_svn_estimator(gr_complex* Prompt_buffer, int length, long fs_in, doubl
*/
float carrier_lock_detector(gr_complex* Prompt_buffer, int length)
{
float tmp_sum_I = 0;
float tmp_sum_Q = 0;
float NBD = 0;
float NBP = 0;
float tmp_sum_I = 0.0;
float tmp_sum_Q = 0.0;
float NBD = 0.0;
float NBP = 0.0;
for (int i = 0; i < length; i++)
{
tmp_sum_I += Prompt_buffer[i].real();

View File

@ -41,11 +41,10 @@
void Tracking_2nd_DLL_filter::calculate_lopp_coef(float* tau1, float* tau2, float lbw, float zeta, float k)
{
// Solve natural frequency
float Wn;
Wn = lbw * 8 * zeta / (4 * zeta * zeta + 1);
float Wn = lbw * 8.0 * zeta / (4.0 * zeta * zeta + 1.0);
// solve for t1 & t2
*tau1 = k / (Wn * Wn);
*tau2 = (2.0 * zeta) / Wn;
*tau2 = 2.0 * zeta / Wn;
}
@ -67,9 +66,7 @@ void Tracking_2nd_DLL_filter::initialize()
float Tracking_2nd_DLL_filter::get_code_nco(float DLL_discriminator)
{
float code_nco;
code_nco = d_old_code_nco + (d_tau2_code / d_tau1_code) * (DLL_discriminator - d_old_code_error) + (DLL_discriminator + d_old_code_error) * (d_pdi_code / (2 * d_tau1_code));
//code_nco = d_old_code_nco + (d_tau2_code/d_tau1_code)*(DLL_discriminator - d_old_code_error) + DLL_discriminator * (d_pdi_code/d_tau1_code);
float code_nco = d_old_code_nco + (d_tau2_code / d_tau1_code) * (DLL_discriminator - d_old_code_error) + (DLL_discriminator + d_old_code_error) * (d_pdi_code / (2.0 * d_tau1_code));
d_old_code_nco = code_nco;
d_old_code_error = DLL_discriminator; //[chips]
return code_nco;

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@ -49,13 +49,13 @@ class Tracking_2nd_DLL_filter
{
private:
// PLL filter parameters
float d_tau1_code = 0;
float d_tau2_code = 0;
float d_pdi_code = 0;
float d_dllnoisebandwidth = 0;
float d_dlldampingratio = 0;
float d_old_code_error = 0;
float d_old_code_nco = 0;
float d_tau1_code = 0.0;
float d_tau2_code = 0.0;
float d_pdi_code = 0.0;
float d_dllnoisebandwidth = 0.0;
float d_dlldampingratio = 0.0;
float d_old_code_error = 0.0;
float d_old_code_nco = 0.0;
void calculate_lopp_coef(float* tau1, float* tau2, float lbw, float zeta, float k);
public:

View File

@ -40,11 +40,10 @@
void Tracking_2nd_PLL_filter::calculate_lopp_coef(float* tau1, float* tau2, float lbw, float zeta, float k)
{
// Solve natural frequency
float Wn;
Wn = lbw * 8 * zeta / (4 * zeta * zeta + 1);
float Wn = lbw * 8.0 * zeta / (4.0 * zeta * zeta + 1.0);
// solve for t1 & t2
*tau1 = k / (Wn * Wn);
*tau2 = (2.0 * zeta) / Wn;
*tau2 = 2.0 * zeta / Wn;
}
@ -71,8 +70,7 @@ void Tracking_2nd_PLL_filter::initialize()
*/
float Tracking_2nd_PLL_filter::get_carrier_nco(float PLL_discriminator)
{
float carr_nco;
carr_nco = d_old_carr_nco + (d_tau2_carr / d_tau1_carr) * (PLL_discriminator - d_old_carr_error) + (PLL_discriminator + d_old_carr_error) * (d_pdi_carr / (2 * d_tau1_carr));
float carr_nco = d_old_carr_nco + (d_tau2_carr / d_tau1_carr) * (PLL_discriminator - d_old_carr_error) + (PLL_discriminator + d_old_carr_error) * (d_pdi_carr / (2.0 * d_tau1_carr));
//carr_nco = d_old_carr_nco + (d_tau2_carr/d_tau1_carr)*(PLL_discriminator - d_old_carr_error) + PLL_discriminator * (d_pdi_carr/d_tau1_carr);
d_old_carr_nco = carr_nco;
d_old_carr_error = PLL_discriminator;

View File

@ -48,15 +48,15 @@ class Tracking_2nd_PLL_filter
{
private:
// PLL filter parameters
float d_tau1_carr = 0;
float d_tau2_carr = 0;
float d_pdi_carr = 0;
float d_tau1_carr = 0.0;
float d_tau2_carr = 0.0;
float d_pdi_carr = 0.0;
float d_pllnoisebandwidth = 0;
float d_plldampingratio = 0;
float d_pllnoisebandwidth = 0.0;
float d_plldampingratio = 0.0;
float d_old_carr_error = 0;
float d_old_carr_nco = 0;
float d_old_carr_error = 0.0;
float d_old_carr_nco = 0.0;
void calculate_lopp_coef(float* tau1, float* tau2, float lbw, float zeta, float k);

View File

@ -83,7 +83,7 @@ double pll_cloop_two_quadrant_atan(gr_complex prompt_s1)
}
else
{
return 0;
return 0.0;
}
}
@ -107,7 +107,7 @@ double dll_nc_e_minus_l_normalized(gr_complex early_s1, gr_complex late_s1)
}
else
{
return 0.5 * (P_early - P_late) / ((P_early + P_late));
return 0.5 * (P_early - P_late) / (P_early + P_late);
}
}
@ -131,6 +131,6 @@ double dll_nc_vemlp_normalized(gr_complex very_early_s1, gr_complex early_s1, gr
}
else
{
return (P_early - P_late) / ((P_early + P_late));
return (P_early - P_late) / (P_early + P_late);
}
}

View File

@ -37,9 +37,6 @@
#include <glog/logging.h>
#define MAX_LOOP_ORDER 3
#define MAX_HISTORY_LENGTH 4
Tracking_loop_filter::Tracking_loop_filter(float update_interval,
float noise_bandwidth,
int loop_order,
@ -50,8 +47,8 @@ Tracking_loop_filter::Tracking_loop_filter(float update_interval,
d_noise_bandwidth(noise_bandwidth),
d_update_interval(update_interval)
{
d_inputs.resize(MAX_HISTORY_LENGTH, 0.0);
d_outputs.resize(MAX_HISTORY_LENGTH, 0.0);
d_inputs.resize(MAX_LOOP_HISTORY_LENGTH, 0.0);
d_outputs.resize(MAX_LOOP_HISTORY_LENGTH, 0.0);
update_coefficients();
}
@ -62,8 +59,8 @@ Tracking_loop_filter::Tracking_loop_filter()
d_noise_bandwidth(15.0),
d_update_interval(0.001)
{
d_inputs.resize(MAX_HISTORY_LENGTH, 0.0);
d_outputs.resize(MAX_HISTORY_LENGTH, 0.0);
d_inputs.resize(MAX_LOOP_HISTORY_LENGTH, 0.0);
d_outputs.resize(MAX_LOOP_HISTORY_LENGTH, 0.0);
update_coefficients();
}
@ -75,12 +72,12 @@ Tracking_loop_filter::~Tracking_loop_filter()
float Tracking_loop_filter::apply(float current_input)
{
// Now apply the filter coefficients:
float result = 0;
float result = 0.0;
// Hanlde the old outputs first:
for (unsigned int ii = 0; ii < d_output_coefficients.size(); ++ii)
{
result += d_output_coefficients[ii] * d_outputs[(d_current_index + ii) % MAX_HISTORY_LENGTH];
result += d_output_coefficients[ii] * d_outputs[(d_current_index + ii) % MAX_LOOP_HISTORY_LENGTH];
}
// Now update the index to handle the inputs.
@ -93,7 +90,7 @@ float Tracking_loop_filter::apply(float current_input)
d_current_index--;
if (d_current_index < 0)
{
d_current_index += MAX_HISTORY_LENGTH;
d_current_index += MAX_LOOP_HISTORY_LENGTH;
}
d_inputs[d_current_index] = current_input;
@ -101,7 +98,7 @@ float Tracking_loop_filter::apply(float current_input)
for (unsigned int ii = 0; ii < d_input_coefficients.size(); ++ii)
{
result += d_input_coefficients[ii] * d_inputs[(d_current_index + ii) % MAX_HISTORY_LENGTH];
result += d_input_coefficients[ii] * d_inputs[(d_current_index + ii) % MAX_LOOP_HISTORY_LENGTH];
}
@ -122,7 +119,7 @@ void Tracking_loop_filter::update_coefficients(void)
float wn;
float T = d_update_interval;
float zeta = 1 / std::sqrt(2);
float zeta = 1.0 / std::sqrt(2.0);
// The following is based on the bilinear transform approximation of
// the analog integrator. The loop format is from Kaplan & Hegarty
@ -146,7 +143,7 @@ void Tracking_loop_filter::update_coefficients(void)
d_input_coefficients[1] = g1 * T / 2.0;
d_output_coefficients.resize(1);
d_output_coefficients[0] = 1;
d_output_coefficients[0] = 1.0;
}
else
{
@ -157,28 +154,28 @@ void Tracking_loop_filter::update_coefficients(void)
}
break;
case 2:
wn = d_noise_bandwidth * (8 * zeta) / (4 * zeta * zeta + 1);
wn = d_noise_bandwidth * (8.0 * zeta) / (4.0 * zeta * zeta + 1.0);
g1 = wn * wn;
g2 = wn * 2 * zeta;
g2 = wn * 2.0 * zeta;
if (d_include_last_integrator)
{
d_input_coefficients.resize(3);
d_input_coefficients[0] = T / 2 * (g1 * T / 2 + g2);
d_input_coefficients[1] = T * T / 2 * g1;
d_input_coefficients[2] = T / 2 * (g1 * T / 2 - g2);
d_input_coefficients[0] = T / 2.0 * (g1 * T / 2.0 + g2);
d_input_coefficients[1] = T * T / 2.0 * g1;
d_input_coefficients[2] = T / 2.0 * (g1 * T / 2.0 - g2);
d_output_coefficients.resize(2);
d_output_coefficients[0] = 2;
d_output_coefficients[1] = -1;
d_output_coefficients[0] = 2.0;
d_output_coefficients[1] = -1.0;
}
else
{
d_input_coefficients.resize(2);
d_input_coefficients[0] = (g1 * T / 2.0 + g2);
d_input_coefficients[1] = g1 * T / 2 - g2;
d_input_coefficients[1] = g1 * T / 2.0 - g2;
d_output_coefficients.resize(1);
d_output_coefficients[0] = 1;
d_output_coefficients[0] = 1.0;
}
break;
@ -193,27 +190,27 @@ void Tracking_loop_filter::update_coefficients(void)
if (d_include_last_integrator)
{
d_input_coefficients.resize(4);
d_input_coefficients[0] = T / 2 * (g3 + T / 2 * (g2 + T / 2 * g1));
d_input_coefficients[1] = T / 2 * (-g3 + T / 2 * (g2 + 3 * T / 2 * g1));
d_input_coefficients[2] = T / 2 * (-g3 - T / 2 * (g2 - 3 * T / 2 * g1));
d_input_coefficients[3] = T / 2 * (g3 - T / 2 * (g2 - T / 2 * g1));
d_input_coefficients[0] = T / 2.0 * (g3 + T / 2.0 * (g2 + T / 2.0 * g1));
d_input_coefficients[1] = T / 2.0 * (-g3 + T / 2.0 * (g2 + 3.0 * T / 2.0 * g1));
d_input_coefficients[2] = T / 2.0 * (-g3 - T / 2.0 * (g2 - 3.0 * T / 2.0 * g1));
d_input_coefficients[3] = T / 2.0 * (g3 - T / 2.0 * (g2 - T / 2.0 * g1));
d_output_coefficients.resize(3);
d_output_coefficients[0] = 3;
d_output_coefficients[1] = -3;
d_output_coefficients[2] = 1;
d_output_coefficients[0] = 3.0;
d_output_coefficients[1] = -3.0;
d_output_coefficients[2] = 1.0;
}
else
{
d_input_coefficients.resize(3);
d_input_coefficients[0] = g3 + T / 2 * (g2 + T / 2 * g1);
d_input_coefficients[1] = g1 * T * T / 2 - 2 * g3;
d_input_coefficients[2] = g3 + T / 2 * (-g2 + T / 2 * g1);
d_input_coefficients[0] = g3 + T / 2.0 * (g2 + T / 2.0 * g1);
d_input_coefficients[1] = g1 * T * T / 2.0 - 2.0 * g3;
d_input_coefficients[2] = g3 + T / 2.0 * (-g2 + T / 2.0 * g1);
d_output_coefficients.resize(2);
d_output_coefficients[0] = 2;
d_output_coefficients[1] = -1;
d_output_coefficients[0] = 2.0;
d_output_coefficients[1] = -1.0;
}
break;
};
@ -254,7 +251,7 @@ bool Tracking_loop_filter::get_include_last_integrator(void) const
void Tracking_loop_filter::set_order(int loop_order)
{
if (loop_order < 1 || loop_order > MAX_LOOP_ORDER)
if (loop_order < 1 or loop_order > MAX_LOOP_ORDER)
{
LOG(ERROR) << "Ignoring attempt to set loop order to " << loop_order
<< ". Maximum allowed order is: " << MAX_LOOP_ORDER
@ -274,7 +271,7 @@ int Tracking_loop_filter::get_order(void) const
void Tracking_loop_filter::initialize(float initial_output)
{
d_inputs.assign(MAX_HISTORY_LENGTH, 0.0);
d_outputs.assign(MAX_HISTORY_LENGTH, initial_output);
d_current_index = MAX_HISTORY_LENGTH - 1;
d_inputs.assign(MAX_LOOP_HISTORY_LENGTH, 0.0);
d_outputs.assign(MAX_LOOP_HISTORY_LENGTH, initial_output);
d_current_index = MAX_LOOP_HISTORY_LENGTH - 1;
}

View File

@ -33,6 +33,8 @@
#ifndef GNSS_SDR_TRACKING_LOOP_FILTER_H_
#define GNSS_SDR_TRACKING_LOOP_FILTER_H_
#define MAX_LOOP_ORDER 3
#define MAX_LOOP_HISTORY_LENGTH 4
#include <vector>