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gnss-sdr/src/algorithms/tracking/gnuradio_blocks/galileo_volk_e1_dll_pll_vem...

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/*!
* \file galileo_volk_e1_dll_pll_veml_tracking_cc.cc
* \brief Implementation of a code DLL + carrier PLL VEML (Very Early
* Minus Late) tracking block for Galileo E1 signals
* \author Luis Esteve, 2012. luis(at)epsilon-formacion.com
*
* 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) 2010-2014 (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 "galileo_volk_e1_dll_pll_veml_tracking_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 "galileo_e1_signal_processing.h"
#include "tracking_discriminators.h"
#include "lock_detectors.h"
#include "Galileo_E1.h"
#include "control_message_factory.h"
#include "volk_gnsssdr/volk_gnsssdr.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;
galileo_volk_e1_dll_pll_veml_tracking_cc_sptr
galileo_volk_e1_dll_pll_veml_make_tracking_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,
float very_early_late_space_chips)
{
return galileo_volk_e1_dll_pll_veml_tracking_cc_sptr(new galileo_volk_e1_dll_pll_veml_tracking_cc(if_freq,
fs_in, vector_length, queue, dump, dump_filename, pll_bw_hz, dll_bw_hz, early_late_space_chips, very_early_late_space_chips));
}
void galileo_volk_e1_dll_pll_veml_tracking_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
}
galileo_volk_e1_dll_pll_veml_tracking_cc::galileo_volk_e1_dll_pll_veml_tracking_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,
float very_early_late_space_chips):
gr::block("galileo_volk_e1_dll_pll_veml_tracking_cc", gr::io_signature::make(1, 1, sizeof(gr_complex)),
gr::io_signature::make(1, 1, sizeof(Gnss_Synchro)))
{
this->set_relative_rate(1.0/vector_length);
// 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;
d_code_loop_filter = Tracking_2nd_DLL_filter(Galileo_E1_CODE_PERIOD);
d_carrier_loop_filter = Tracking_2nd_PLL_filter(Galileo_E1_CODE_PERIOD);
// Initialize tracking ==========================================
// Set bandwidth of code and carrier loop filters
d_code_loop_filter.set_DLL_BW(dll_bw_hz);
d_carrier_loop_filter.set_PLL_BW(pll_bw_hz);
// Correlator spacing
d_early_late_spc_chips = early_late_space_chips; // Define early-late offset (in chips)
d_very_early_late_spc_chips = very_early_late_space_chips; // Define very-early-late offset (in chips)
// Initialization of local code replica
// Get space for a vector with the sinboc(1,1) replica sampled 2x/chip
d_ca_code = static_cast<gr_complex*>(volk_malloc((2 * Galileo_E1_B_CODE_LENGTH_CHIPS + 4) * sizeof(gr_complex), volk_get_alignment()));
d_very_early_code = static_cast<gr_complex*>(volk_malloc(2 * d_vector_length * sizeof(gr_complex), volk_get_alignment()));
d_early_code = static_cast<gr_complex*>(volk_malloc(2 * d_vector_length * sizeof(gr_complex), volk_get_alignment()));
d_prompt_code = static_cast<gr_complex*>(volk_malloc(2 * d_vector_length * sizeof(gr_complex), volk_get_alignment()));
d_late_code = static_cast<gr_complex*>(volk_malloc(2 * d_vector_length * sizeof(gr_complex), volk_get_alignment()));
d_very_late_code = static_cast<gr_complex*>(volk_malloc(2 * d_vector_length * sizeof(gr_complex), volk_get_alignment()));
d_carr_sign = static_cast<gr_complex*>(volk_malloc(2*d_vector_length * sizeof(gr_complex), volk_get_alignment()));
d_very_early_code16=static_cast<lv_16sc_t*>(volk_malloc(2 * d_vector_length * sizeof(lv_16sc_t), volk_get_alignment()));
d_early_code16=static_cast<lv_16sc_t*>(volk_malloc(2 * d_vector_length * sizeof(lv_16sc_t), volk_get_alignment()));
d_prompt_code16=static_cast<lv_16sc_t*>(volk_malloc(2 * d_vector_length * sizeof(lv_16sc_t), volk_get_alignment()));
d_late_code16=static_cast<lv_16sc_t*>(volk_malloc(2 * d_vector_length * sizeof(lv_16sc_t), volk_get_alignment()));
d_very_late_code16=static_cast<lv_16sc_t*>(volk_malloc(2 * d_vector_length * sizeof(lv_16sc_t), volk_get_alignment()));
d_carr_sign16=static_cast<lv_16sc_t*>(volk_malloc(2 * d_vector_length * sizeof(lv_16sc_t), volk_get_alignment()));
in16=static_cast<lv_16sc_t*>(volk_malloc(2 * d_vector_length * sizeof(lv_16sc_t), volk_get_alignment()));
d_very_early_code8=static_cast<lv_8sc_t*>(volk_malloc(2 * d_vector_length * sizeof(lv_8sc_t), volk_get_alignment()));
d_early_code8=static_cast<lv_8sc_t*>(volk_malloc(2 * d_vector_length * sizeof(lv_8sc_t), volk_get_alignment()));
d_prompt_code8=static_cast<lv_8sc_t*>(volk_malloc(2 * d_vector_length * sizeof(lv_8sc_t), volk_get_alignment()));
d_late_code8=static_cast<lv_8sc_t*>(volk_malloc(2 * d_vector_length * sizeof(lv_8sc_t), volk_get_alignment()));
d_very_late_code8=static_cast<lv_8sc_t*>(volk_malloc(2 * d_vector_length * sizeof(lv_8sc_t), volk_get_alignment()));
d_carr_sign8=static_cast<lv_8sc_t*>(volk_malloc(2 * d_vector_length * sizeof(lv_8sc_t), volk_get_alignment()));
in8=static_cast<lv_8sc_t*>(volk_malloc(2 * d_vector_length * sizeof(lv_8sc_t), volk_get_alignment()));
// correlator outputs (scalar)
d_Very_Early = static_cast<gr_complex*>(volk_malloc(sizeof(gr_complex), volk_get_alignment()));
d_Early = static_cast<gr_complex*>(volk_malloc(sizeof(gr_complex), volk_get_alignment()));
d_Prompt = static_cast<gr_complex*>(volk_malloc(sizeof(gr_complex), volk_get_alignment()));
d_Late = static_cast<gr_complex*>(volk_malloc(sizeof(gr_complex), volk_get_alignment()));
d_Very_Late = static_cast<gr_complex*>(volk_malloc(sizeof(gr_complex), volk_get_alignment()));
//--- Initializations ------------------------------
// Initial code frequency basis of NCO
d_code_freq_chips = static_cast<double>(Galileo_E1_CODE_CHIP_RATE_HZ);
// Residual code phase (in chips)
d_rem_code_phase_samples = 0.0;
// 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["E"] = std::string("Galileo");
*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);
}
void galileo_volk_e1_dll_pll_veml_tracking_cc::start_tracking()
{
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;
// 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 2 (2 samples per chip)
galileo_e1_code_gen_complex_sampled(&d_ca_code[2],
d_acquisition_gnss_synchro->Signal,
false,
d_acquisition_gnss_synchro->PRN,
2 * Galileo_E1_CODE_CHIP_RATE_HZ,
0);
// Fill head and tail
d_ca_code[0] = d_ca_code[static_cast<int>(2 * Galileo_E1_B_CODE_LENGTH_CHIPS)];
d_ca_code[1] = d_ca_code[static_cast<int>(2 * Galileo_E1_B_CODE_LENGTH_CHIPS + 1)];
d_ca_code[static_cast<int>(2 * Galileo_E1_B_CODE_LENGTH_CHIPS + 2)] = d_ca_code[2];
d_ca_code[static_cast<int>(2 * Galileo_E1_B_CODE_LENGTH_CHIPS + 3)] = d_ca_code[3];
d_carrier_lock_fail_counter = 0;
d_rem_code_phase_samples = 0.0;
d_rem_carr_phase_rad = 0;
d_acc_carrier_phase_rad = 0;
d_acc_code_phase_secs = 0;
d_carrier_doppler_hz = d_acq_carrier_doppler_hz;
d_current_prn_length_samples = d_vector_length;
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
<< " PULL-IN Code Phase [samples]=" << d_acq_code_phase_samples;
}
void galileo_volk_e1_dll_pll_veml_tracking_cc::update_local_code()
{
double tcode_half_chips;
float rem_code_phase_half_chips;
int code_length_half_chips = static_cast<int>(Galileo_E1_B_CODE_LENGTH_CHIPS) * 2;
double code_phase_step_chips;
double code_phase_step_half_chips;
int early_late_spc_samples;
int very_early_late_spc_samples;
int epl_loop_length_samples;
// unified loop for VE, E, P, L, VL code vectors
code_phase_step_chips = (static_cast<double>(d_code_freq_chips)) / (static_cast<double>(d_fs_in));
code_phase_step_half_chips = (2.0 * static_cast<double>(d_code_freq_chips)) / (static_cast<double>(d_fs_in));
rem_code_phase_half_chips = d_rem_code_phase_samples * (2*d_code_freq_chips / d_fs_in);
tcode_half_chips = - static_cast<double>(rem_code_phase_half_chips);
early_late_spc_samples = round(d_early_late_spc_chips / code_phase_step_chips);
very_early_late_spc_samples = round(d_very_early_late_spc_chips / code_phase_step_chips);
epl_loop_length_samples = d_current_prn_length_samples + very_early_late_spc_samples * 2;
//HERE YOU CAN CHOOSE THE DESIRED VOLK IMPLEMENTATION
//volk_gnsssdr_32fc_s32f_x4_update_local_code_32fc_manual(d_very_early_code, (float) d_very_early_late_spc_chips, (float) code_length_half_chips, (float) code_phase_step_half_chips, (float) tcode_half_chips, d_ca_code, epl_loop_length_samples, "generic");
volk_gnsssdr_32fc_s32f_x4_update_local_code_32fc(d_very_early_code, (float) d_very_early_late_spc_chips, (float) code_length_half_chips, (float) code_phase_step_half_chips, (float) tcode_half_chips, d_ca_code, epl_loop_length_samples);
memcpy(d_early_code, &d_very_early_code[very_early_late_spc_samples - early_late_spc_samples], d_current_prn_length_samples * sizeof(gr_complex));
memcpy(d_prompt_code, &d_very_early_code[very_early_late_spc_samples], d_current_prn_length_samples * sizeof(gr_complex));
memcpy(d_late_code, &d_very_early_code[very_early_late_spc_samples + early_late_spc_samples], d_current_prn_length_samples * sizeof(gr_complex));
memcpy(d_very_late_code, &d_very_early_code[2 * very_early_late_spc_samples], d_current_prn_length_samples * sizeof(gr_complex));
}
void galileo_volk_e1_dll_pll_veml_tracking_cc::update_local_carrier()
{
float phase_rad, phase_step_rad;
// Compute the carrier phase step for the K-1 carrier doppler estimation
phase_step_rad = static_cast<float>(GPS_TWO_PI) * d_carrier_doppler_hz / static_cast<float>(d_fs_in);
// Initialize the carrier phase with the remanent carrier phase of the K-2 loop
phase_rad = d_rem_carr_phase_rad;
//HERE YOU CAN CHOOSE THE DESIRED VOLK IMPLEMENTATION
//volk_gnsssdr_s32f_x2_update_local_carrier_32fc_manual(d_carr_sign, phase_rad, phase_step_rad, d_current_prn_length_samples, "generic");
//volk_gnsssdr_s32f_x2_update_local_carrier_32fc_manual(d_carr_sign, phase_rad, phase_step_rad, d_current_prn_length_samples, "u_sse2");
volk_gnsssdr_s32f_x2_update_local_carrier_32fc(d_carr_sign, phase_rad, phase_step_rad, d_current_prn_length_samples);
}
galileo_volk_e1_dll_pll_veml_tracking_cc::~galileo_volk_e1_dll_pll_veml_tracking_cc()
{
d_dump_file.close();
volk_free(d_very_early_code);
volk_free(d_early_code);
volk_free(d_prompt_code);
volk_free(d_late_code);
volk_free(d_very_late_code);
volk_free(d_carr_sign);
volk_free(d_Very_Early);
volk_free(d_Early);
volk_free(d_Prompt);
volk_free(d_Late);
volk_free(d_Very_Late);
volk_free(d_ca_code);
volk_free(d_very_early_code16);
volk_free(d_early_code16);
volk_free(d_prompt_code16);
volk_free(d_late_code16);
volk_free(d_very_late_code16);
volk_free(d_carr_sign16);
volk_free(in16);
volk_free(d_very_early_code8);
volk_free(d_early_code8);
volk_free(d_prompt_code8);
volk_free(d_late_code8);
volk_free(d_very_late_code8);
volk_free(d_carr_sign8);
volk_free(in8);
delete[] d_Prompt_buffer;
}
int galileo_volk_e1_dll_pll_veml_tracking_cc::general_work (int noutput_items,gr_vector_int &ninput_items,
gr_vector_const_void_star &input_items, gr_vector_void_star &output_items)
{
float carr_error_hz;
float carr_error_filt_hz;
float code_error_chips;
float code_error_filt_chips;
if (d_enable_tracking == true)
{
if (d_pull_in == true)
{
/*
* Signal alignment (skip samples until the incoming signal is aligned with local replica)
*/
int samples_offset;
float 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);
d_sample_counter = d_sample_counter + samples_offset; //count for the processed samples
d_pull_in = false;
consume_each(samples_offset); //shift input to perform alignment with local replica
return 1;
}
// GNSS_SYNCHRO OBJECT to interchange data between tracking->telemetry_decoder
Gnss_Synchro current_synchro_data;
// Fill the acquisition data
current_synchro_data = *d_acquisition_gnss_synchro;
// 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];
// Generate local code and carrier replicas (using \hat{f}_d(k-1))
update_local_code();
update_local_carrier();
// perform carrier wipe-off and compute Very Early, Early, Prompt, Late and Very Late correlation
//HERE YOU CAN CHOOSE THE DESIRED VOLK IMPLEMENTATION
//Float implementation:
//volk_gnsssdr_32fc_x7_cw_vepl_corr_32fc_x5(d_Very_Early, d_Early, d_Prompt, d_Late, d_Very_Late, in, d_carr_sign, d_very_early_code, d_early_code, d_prompt_code, d_late_code, d_very_late_code, d_current_prn_length_samples, "generic");
//volk_gnsssdr_32fc_x7_cw_vepl_corr_32fc_x5(d_Very_Early, d_Early, d_Prompt, d_Late, d_Very_Late, in, d_carr_sign, d_very_early_code, d_early_code, d_prompt_code, d_late_code, d_very_late_code, d_current_prn_length_samples, "u_avx");
//Integer 16 bits implementation
/*volk_gnsssdr_32fc_convert_16ic(d_very_early_code16, d_very_early_code, d_current_prn_length_samples);
volk_gnsssdr_32fc_convert_16ic(d_early_code16, d_early_code, d_current_prn_length_samples);
volk_gnsssdr_32fc_convert_16ic(d_prompt_code16, d_prompt_code, d_current_prn_length_samples);
volk_gnsssdr_32fc_convert_16ic(d_late_code16, d_late_code, d_current_prn_length_samples);
volk_gnsssdr_32fc_convert_16ic(d_very_late_code16, d_very_late_code, d_current_prn_length_samples);
volk_gnsssdr_32fc_convert_16ic(in16, in, d_current_prn_length_samples);
volk_gnsssdr_32fc_convert_16ic(d_carr_sign16, d_carr_sign, d_current_prn_length_samples);
volk_gnsssdr_16ic_x7_cw_vepl_corr_32fc_x5(d_Very_Early, d_Early, d_Prompt, d_Late, d_Very_Late, in16, d_carr_sign16, d_very_early_code16, d_early_code16, d_prompt_code16, d_late_code16, d_very_late_code16, d_current_prn_length_samples);*/
//Integer 8 bits implementation
volk_gnsssdr_32fc_convert_8ic(d_very_early_code8, d_very_early_code, d_current_prn_length_samples);
volk_gnsssdr_32fc_convert_8ic(d_early_code8, d_early_code, d_current_prn_length_samples);
volk_gnsssdr_32fc_convert_8ic(d_prompt_code8, d_prompt_code, d_current_prn_length_samples);
volk_gnsssdr_32fc_convert_8ic(d_late_code8, d_late_code, d_current_prn_length_samples);
volk_gnsssdr_32fc_convert_8ic(d_very_late_code8, d_very_late_code, d_current_prn_length_samples);
volk_gnsssdr_32fc_convert_8ic(d_carr_sign8, d_carr_sign, d_current_prn_length_samples);
volk_gnsssdr_32fc_s32f_convert_8ic(in8, in, 4, d_current_prn_length_samples);
volk_gnsssdr_8ic_x7_cw_vepl_corr_safe_32fc_x5(d_Very_Early, d_Early, d_Prompt, d_Late, d_Very_Late, in8, d_carr_sign8, d_very_early_code8, d_early_code8, d_prompt_code8, d_late_code8, d_very_late_code8, d_current_prn_length_samples);
// ################## PLL ##########################################################
// PLL discriminator
carr_error_hz = pll_cloop_two_quadrant_atan(*d_Prompt) / static_cast<float>(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 = Galileo_E1_CODE_CHIP_RATE_HZ + ((d_carrier_doppler_hz * Galileo_E1_CODE_CHIP_RATE_HZ) / Galileo_E1_FREQ_HZ);
//carrier phase accumulator for (K) Doppler estimation
d_acc_carrier_phase_rad = d_acc_carrier_phase_rad + GPS_TWO_PI * d_carrier_doppler_hz * Galileo_E1_CODE_PERIOD;
//remnant 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 * Galileo_E1_CODE_PERIOD;
d_rem_carr_phase_rad = fmod(d_rem_carr_phase_rad, GPS_TWO_PI);
// ################## DLL ##########################################################
// DLL discriminator
code_error_chips = dll_nc_vemlp_normalized(*d_Very_Early, *d_Early, *d_Late, *d_Very_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
float code_error_filt_secs;
code_error_filt_secs = (Galileo_E1_CODE_PERIOD * code_error_filt_chips) / Galileo_E1_CODE_CHIP_RATE_HZ; //[seconds]
//code_error_filt_secs=T_prn_seconds*code_error_filt_chips*T_chip_seconds*static_cast<float>(d_fs_in); //[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 lenght 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 * Galileo_E1_B_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, Galileo_E1_B_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 results to Telemetry block ##########
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
d_rem_code_phase_samples = K_blk_samples - d_current_prn_length_samples; //rounding error < 1 sample
// 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 = static_cast<double>(d_acc_carrier_phase_rad);
current_synchro_data.Carrier_Doppler_hz = static_cast<double>(d_carrier_doppler_hz);
current_synchro_data.CN0_dB_hz = static_cast<double>(d_CN0_SNV_dB_Hz);
*out[0] = current_synchro_data;
// ########## DEBUG OUTPUT
/*!
* \todo The stop timer has to be moved to the signal source!
*/
// 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;
}
tmp_str_stream << "Tracking CH " << d_channel << ": Satellite " << Gnss_Satellite(systemName[sys], d_acquisition_gnss_synchro->PRN)
<< ", Doppler=" << d_carrier_doppler_hz << " [Hz] CN0 = " << d_CN0_SNV_dB_Hz << " [dB-Hz]" << std::endl;
LOG(INFO) << tmp_str_stream.rdbuf() << std::flush;
//if (d_channel == 0 || d_last_seg==5) d_carrier_lock_fail_counter=500; //DEBUG: force unlock!
}
}
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);
Gnss_Synchro **out = (Gnss_Synchro **) &output_items[0]; //block output stream pointer
// GNSS_SYNCHRO OBJECT to interchange data between tracking->telemetry_decoder
*out[0] = *d_acquisition_gnss_synchro;
}
if(d_dump)
{
// Dump results to file
float prompt_I;
float prompt_Q;
float tmp_VE, tmp_E, tmp_P, tmp_L, tmp_VL;
float tmp_float;
double tmp_double;
prompt_I = (*d_Prompt).real();
prompt_Q = (*d_Prompt).imag();
tmp_VE = std::abs<float>(*d_Very_Early);
tmp_E = std::abs<float>(*d_Early);
tmp_P = std::abs<float>(*d_Prompt);
tmp_L = std::abs<float>(*d_Late);
tmp_VL = std::abs<float>(*d_Very_Late);
try
{
// Dump correlators output
d_dump_file.write(reinterpret_cast<char*>(&tmp_VE), sizeof(float));
d_dump_file.write(reinterpret_cast<char*>(&tmp_E), sizeof(float));
d_dump_file.write(reinterpret_cast<char*>(&tmp_P), sizeof(float));
d_dump_file.write(reinterpret_cast<char*>(&tmp_L), sizeof(float));
d_dump_file.write(reinterpret_cast<char*>(&tmp_VL), sizeof(float));
// PROMPT I and Q (to analyze navigation symbols)
d_dump_file.write(reinterpret_cast<char*>(&prompt_I), sizeof(float));
d_dump_file.write(reinterpret_cast<char*>(&prompt_Q), sizeof(float));
// PRN start sample stamp
d_dump_file.write(reinterpret_cast<char*>(&d_sample_counter), sizeof(unsigned long int));
// accumulated carrier phase
d_dump_file.write(reinterpret_cast<char*>(&d_acc_carrier_phase_rad), sizeof(float));
// carrier and code frequency
d_dump_file.write(reinterpret_cast<char*>(&d_carrier_doppler_hz), sizeof(float));
d_dump_file.write(reinterpret_cast<char*>(&d_code_freq_chips), sizeof(float));
//PLL commands
d_dump_file.write(reinterpret_cast<char*>(&carr_error_hz), sizeof(float));
d_dump_file.write(reinterpret_cast<char*>(&carr_error_filt_hz), sizeof(float));
//DLL commands
d_dump_file.write(reinterpret_cast<char*>(&code_error_chips), sizeof(float));
d_dump_file.write(reinterpret_cast<char*>(&code_error_filt_chips), sizeof(float));
// CN0 and carrier lock test
d_dump_file.write(reinterpret_cast<char*>(&d_CN0_SNV_dB_Hz), sizeof(float));
d_dump_file.write(reinterpret_cast<char*>(&d_carrier_lock_test), sizeof(float));
// AUX vars (for debug purposes)
tmp_float = d_rem_code_phase_samples;
d_dump_file.write(reinterpret_cast<char*>(&tmp_float), sizeof(float));
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)
{
LOG(WARNING) << "Exception writing trk dump file " << e.what() << std::endl;
}
}
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
//std::cout<<"Galileo tracking output at sample "<<d_sample_counter<<std::endl;
return 1; //output tracking result ALWAYS even in the case of d_enable_tracking==false
}
void galileo_volk_e1_dll_pll_veml_tracking_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();
}
catch (std::ifstream::failure e)
{
LOG(WARNING) << "channel " << d_channel << " Exception opening trk dump file " << e.what() << std::endl;
}
}
}
}
void galileo_volk_e1_dll_pll_veml_tracking_cc::set_channel_queue(concurrent_queue<int> *channel_internal_queue)
{
d_channel_internal_queue = channel_internal_queue;
}
void galileo_volk_e1_dll_pll_veml_tracking_cc::set_gnss_synchro(Gnss_Synchro* p_gnss_synchro)
{
d_acquisition_gnss_synchro = p_gnss_synchro;
// Gnss_Satellite(satellite.get_system(), satellite.get_PRN());
//DLOG(INFO) << "Tracking code phase set to " << d_acq_code_phase_samples;
//DLOG(INFO) << "Tracking carrier doppler set to " << d_acq_carrier_doppler_hz;
//DLOG(INFO) << "Tracking Satellite set to " << d_satellite;
}
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