mirror of https://github.com/gnss-sdr/gnss-sdr
1334 lines
62 KiB
C++
Executable File
1334 lines
62 KiB
C++
Executable File
/*!
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* \file dll_pll_veml_tracking.cc
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* \brief Implementation of a code DLL + carrier PLL VEML (Very Early
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* Minus Late) tracking block for Galileo E1 signals
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* \author Luis Esteve, 2012. luis(at)epsilon-formacion.com
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*
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* Code DLL + carrier PLL according to the algorithms described in:
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* [1] K.Borre, D.M.Akos, N.Bertelsen, P.Rinder, and S.H.Jensen,
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* A Software-Defined GPS and Galileo Receiver. A Single-Frequency
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* Approach, Birkhauser, 2007
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*
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* -------------------------------------------------------------------------
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*
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* Copyright (C) 2010-2017 (see AUTHORS file for a list of contributors)
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*
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* GNSS-SDR is a software defined Global Navigation
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* Satellite Systems receiver
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*
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* This file is part of GNSS-SDR.
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*
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* GNSS-SDR is free software: you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation, either version 3 of the License, or
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* (at your option) any later version.
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*
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* GNSS-SDR is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with GNSS-SDR. If not, see <http://www.gnu.org/licenses/>.
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*
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* -------------------------------------------------------------------------
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*/
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#include "dll_pll_veml_tracking.h"
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#include <cmath>
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#include <iostream>
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#include <sstream>
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#include <algorithm>
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#include <boost/lexical_cast.hpp>
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#include <gnuradio/io_signature.h>
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#include <glog/logging.h>
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#include <matio.h>
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#include <volk_gnsssdr/volk_gnsssdr.h>
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#include "tracking_discriminators.h"
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#include "lock_detectors.h"
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#include "control_message_factory.h"
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#include "Galileo_E1.h"
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#include "galileo_e1_signal_processing.h"
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#include "Galileo_E5a.h"
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#include "GPS_L1_CA.h"
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#include "GPS_L2C.h"
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#include "GPS_L5.h"
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using google::LogMessage;
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dll_pll_veml_tracking_sptr dll_pll_veml_make_tracking(
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double fs_in,
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unsigned int vector_length,
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bool dump,
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std::string dump_filename,
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float pll_bw_hz,
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float dll_bw_hz,
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float pll_bw_narrow_hz,
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float dll_bw_narrow_hz,
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float early_late_space_chips,
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float very_early_late_space_chips,
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float early_late_space_narrow_chips,
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float very_early_late_space_narrow_chips,
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int extend_correlation_symbols,
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bool track_pilot,
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char system, char signal[3], bool veml)
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{
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return dll_pll_veml_tracking_sptr(new dll_pll_veml_tracking(
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fs_in,
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vector_length,
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dump,
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dump_filename,
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pll_bw_hz,
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dll_bw_hz,
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pll_bw_narrow_hz,
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dll_bw_narrow_hz,
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early_late_space_chips,
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very_early_late_space_chips,
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early_late_space_narrow_chips,
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very_early_late_space_narrow_chips,
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extend_correlation_symbols,
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track_pilot, system, signal, veml));
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}
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void dll_pll_veml_tracking::forecast(int noutput_items,
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gr_vector_int &ninput_items_required)
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{
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if (noutput_items != 0)
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{
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ninput_items_required[0] = static_cast<int>(d_vector_length) * 2;
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}
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}
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dll_pll_veml_tracking::dll_pll_veml_tracking(
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double fs_in, unsigned int vector_length, bool dump,
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std::string dump_filename, float pll_bw_hz, float dll_bw_hz,
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float pll_bw_narrow_hz, float dll_bw_narrow_hz,
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float early_late_space_chips, float very_early_late_space_chips,
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float early_late_space_narrow_chips, float very_early_late_space_narrow_chips,
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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)),
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gr::io_signature::make(1, 1, sizeof(Gnss_Synchro)))
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{
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// Telemetry bit synchronization message port input
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this->message_port_register_in(pmt::mp("preamble_timestamp_s"));
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this->message_port_register_out(pmt::mp("events"));
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this->set_relative_rate(1.0 / static_cast<double>(vector_length));
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// initialize internal vars
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d_dump = dump;
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d_veml = veml;
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d_track_pilot = track_pilot;
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d_fs_in = fs_in;
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d_vector_length = vector_length;
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d_dump_filename = dump_filename;
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d_code_period = 0.0;
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d_code_chip_rate = 0.0;
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d_signal_carrier_freq = 0.0;
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d_code_length_chips = 0;
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d_secondary = false;
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d_secondary_code_length = 0;
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d_secondary_code_string = nullptr;
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d_correlation_length_ms = 0;
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signal_type = std::string(signal);
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if (system == 'G')
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{
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systemName = "GPS";
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if (signal_type.compare("1C") == 0)
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{
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d_signal_carrier_freq = GPS_L1_FREQ_HZ;
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d_code_period = GPS_L1_CA_CODE_PERIOD;
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d_code_chip_rate = GPS_L1_CA_CODE_RATE_HZ;
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d_correlation_length_ms = 1;
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d_code_length_chips = static_cast<unsigned int>(GPS_L1_CA_CODE_LENGTH_CHIPS);
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d_secondary = false;
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d_track_pilot = false;
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}
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else if (signal_type.compare("2S") == 0)
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{
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d_signal_carrier_freq = GPS_L2_FREQ_HZ;
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d_code_period = GPS_L2_M_PERIOD;
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d_code_chip_rate = GPS_L2_M_CODE_RATE_HZ;
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d_code_length_chips = static_cast<unsigned int>(GPS_L2_M_CODE_LENGTH_CHIPS);
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d_correlation_length_ms = 20;
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d_secondary = false;
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d_track_pilot = false;
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}
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else if (signal_type.compare("L5") == 0)
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{
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d_signal_carrier_freq = GPS_L5_FREQ_HZ;
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d_code_period = GPS_L5i_PERIOD;
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d_code_chip_rate = GPS_L5i_CODE_RATE_HZ;
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d_correlation_length_ms = 1;
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d_code_length_chips = static_cast<unsigned int>(GPS_L5i_CODE_LENGTH_CHIPS);
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d_secondary = false;
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}
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else
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{
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LOG(WARNING) << "Invalid Signal argument when instantiating tracking blocks";
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std::cout << "Invalid Signal argument when instantiating tracking blocks" << std::endl;
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}
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}
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else if (system == 'E')
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{
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systemName = "Galileo";
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if (signal_type.compare("1B") == 0)
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{
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d_signal_carrier_freq = Galileo_E1_FREQ_HZ;
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d_code_period = Galileo_E1_CODE_PERIOD;
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d_code_chip_rate = Galileo_E1_CODE_CHIP_RATE_HZ;
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d_code_length_chips = static_cast<unsigned int>(Galileo_E1_B_CODE_LENGTH_CHIPS);
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d_correlation_length_ms = 4;
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d_secondary = true;
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if (d_track_pilot)
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{
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d_secondary_code_length = static_cast<unsigned int>(Galileo_E1_C_SECONDARY_CODE_LENGTH);
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d_secondary_code_string = const_cast<std::string *>(&Galileo_E1_C_SECONDARY_CODE);
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}
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else
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{
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d_secondary = false;
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}
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}
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else if (signal_type.compare("5X") == 0)
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{
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d_signal_carrier_freq = Galileo_E5a_FREQ_HZ;
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d_code_period = GALILEO_E5a_CODE_PERIOD;
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d_code_chip_rate = Galileo_E5a_CODE_CHIP_RATE_HZ;
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d_correlation_length_ms = 1;
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d_code_length_chips = static_cast<unsigned int>(Galileo_E5a_CODE_LENGTH_CHIPS);
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d_secondary = true;
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if (d_track_pilot)
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{
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d_secondary_code_length = static_cast<unsigned int>(Galileo_E5a_Q_SECONDARY_CODE_LENGTH);
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}
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else
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{
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d_secondary_code_length = static_cast<unsigned int>(Galileo_E5a_I_SECONDARY_CODE_LENGTH);
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d_secondary_code_string = const_cast<std::string *>(&Galileo_E5a_I_SECONDARY_CODE);
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}
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}
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else
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{
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LOG(WARNING) << "Invalid Signal argument when instantiating tracking blocks";
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std::cout << "Invalid Signal argument when instantiating tracking blocks" << std::endl;
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}
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}
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else
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{
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LOG(WARNING) << "Invalid System argument when instantiating tracking blocks";
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std::cout << "Invalid System argument when instantiating tracking blocks" << std::endl;
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}
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d_code_loop_filter = Tracking_2nd_DLL_filter(d_code_period);
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d_carrier_loop_filter = Tracking_2nd_PLL_filter(d_code_period);
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// Initialize tracking ==========================================
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// Set bandwidth of code and carrier loop filters
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d_dll_bw_hz = dll_bw_hz;
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d_pll_bw_hz = pll_bw_hz;
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d_dll_bw_narrow_hz = dll_bw_narrow_hz;
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d_pll_bw_narrow_hz = pll_bw_narrow_hz;
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d_code_loop_filter.set_DLL_BW(d_dll_bw_hz);
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d_carrier_loop_filter.set_PLL_BW(d_pll_bw_hz);
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// Correlator spacing
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d_early_late_spc_chips = early_late_space_chips; // Define early-late offset (in chips)
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d_very_early_late_spc_chips = very_early_late_space_chips; // Define very-early-late offset (in chips)
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d_early_late_spc_narrow_chips = early_late_space_narrow_chips; // Define narrow early-late offset (in chips)
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d_very_early_late_spc_narrow_chips = very_early_late_space_narrow_chips; // Define narrow very-early-late offset (in chips)
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// Initialization of local code replica
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// Get space for a vector with the sinboc(1,1) replica sampled 2x/chip
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d_tracking_code = static_cast<float *>(volk_gnsssdr_malloc(2 * d_code_length_chips * sizeof(float), volk_gnsssdr_get_alignment()));
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// correlator outputs (scalar)
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if (d_veml)
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{
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// Very-Early, Early, Prompt, Late, Very-Late
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d_n_correlator_taps = 5;
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}
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else
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{
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// Early, Prompt, Late
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d_n_correlator_taps = 3;
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}
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d_correlator_outs = static_cast<gr_complex *>(volk_gnsssdr_malloc(d_n_correlator_taps * sizeof(gr_complex), volk_gnsssdr_get_alignment()));
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d_local_code_shift_chips = static_cast<float *>(volk_gnsssdr_malloc(d_n_correlator_taps * sizeof(float), volk_gnsssdr_get_alignment()));
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std::fill_n(d_correlator_outs, d_n_correlator_taps, gr_complex(0.0, 0.0));
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// map memory pointers of correlator outputs
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if (d_veml)
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{
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d_Very_Early = &d_correlator_outs[0];
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d_Early = &d_correlator_outs[1];
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d_Prompt = &d_correlator_outs[2];
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d_Late = &d_correlator_outs[3];
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d_Very_Late = &d_correlator_outs[4];
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d_local_code_shift_chips[0] = -d_very_early_late_spc_chips;
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d_local_code_shift_chips[1] = -d_early_late_spc_chips;
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d_local_code_shift_chips[2] = 0.0;
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d_local_code_shift_chips[3] = d_early_late_spc_chips;
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d_local_code_shift_chips[4] = d_very_early_late_spc_chips;
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d_null_shift = &d_local_code_shift_chips[2];
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}
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else
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{
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d_Very_Early = nullptr;
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d_Early = &d_correlator_outs[0];
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d_Prompt = &d_correlator_outs[1];
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d_Late = &d_correlator_outs[2];
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d_Very_Late = nullptr;
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d_local_code_shift_chips[0] = -d_early_late_spc_chips;
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d_local_code_shift_chips[1] = 0.0;
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d_local_code_shift_chips[2] = d_early_late_spc_chips;
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d_null_shift = &d_local_code_shift_chips[1];
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}
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d_correlation_length_samples = d_vector_length;
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multicorrelator_cpu.init(2 * d_correlation_length_samples, d_n_correlator_taps);
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d_extend_correlation_symbols = extend_correlation_symbols;
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// Enable Data component prompt correlator (slave to Pilot prompt) if tracking uses Pilot signal
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if (d_track_pilot)
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{
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// extended integration control
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if (d_extend_correlation_symbols > 1)
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{
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d_enable_extended_integration = true;
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}
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else
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{
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d_enable_extended_integration = false;
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}
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// Extra correlator for the data component
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correlator_data_cpu.init(2 * d_correlation_length_samples, 1);
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d_Prompt_Data = static_cast<gr_complex *>(volk_gnsssdr_malloc(sizeof(gr_complex), volk_gnsssdr_get_alignment()));
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d_Prompt_Data[0] = gr_complex(0.0, 0.0);
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d_data_code = static_cast<float *>(volk_gnsssdr_malloc(2 * d_code_length_chips * sizeof(float), volk_gnsssdr_get_alignment()));
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}
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else
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{
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// Disable extended integration if data component tracking is selected
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d_enable_extended_integration = false;
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}
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//--- Initializations ---//
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// Initial code frequency basis of NCO
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d_code_freq_chips = d_code_chip_rate;
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// Residual code phase (in chips)
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d_rem_code_phase_samples = 0.0;
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// Residual carrier phase
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d_rem_carr_phase_rad = 0.0;
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// sample synchronization
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d_sample_counter = 0;
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d_acq_sample_stamp = 0;
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d_current_prn_length_samples = static_cast<int>(d_vector_length);
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// CN0 estimation and lock detector buffers
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d_cn0_estimation_counter = 0;
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d_Prompt_buffer = new gr_complex[DLL_PLL_CN0_ESTIMATION_SAMPLES];
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d_carrier_lock_test = 1.0;
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d_CN0_SNV_dB_Hz = 0.0;
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d_carrier_lock_fail_counter = 0;
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d_carrier_lock_threshold = DLL_PLL_CARRIER_LOCK_THRESHOLD;
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clear_tracking_vars();
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d_acquisition_gnss_synchro = nullptr;
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d_channel = 0;
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d_acq_code_phase_samples = 0.0;
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d_acq_carrier_doppler_hz = 0.0;
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d_carrier_doppler_hz = 0.0;
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d_acc_carrier_phase_rad = 0.0;
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d_extend_correlation_symbols_count = 0;
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d_code_phase_step_chips = 0.0;
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d_carrier_phase_step_rad = 0.0;
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d_rem_code_phase_chips = 0.0;
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d_K_blk_samples = 0.0;
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d_code_phase_samples = 0.0;
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d_state = 0; // initial state: standby
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}
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void dll_pll_veml_tracking::start_tracking()
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{
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gr::thread::scoped_lock l(d_setlock);
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/*
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* correct the code phase according to the delay between acq and trk
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*/
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d_acq_code_phase_samples = d_acquisition_gnss_synchro->Acq_delay_samples;
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d_acq_carrier_doppler_hz = d_acquisition_gnss_synchro->Acq_doppler_hz;
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d_acq_sample_stamp = d_acquisition_gnss_synchro->Acq_samplestamp_samples;
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long int acq_trk_diff_samples = static_cast<long int>(d_sample_counter) - static_cast<long int>(d_acq_sample_stamp); //-d_vector_length;
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DLOG(INFO) << "Number of samples between Acquisition and Tracking = " << acq_trk_diff_samples;
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double acq_trk_diff_seconds = static_cast<double>(acq_trk_diff_samples) / d_fs_in;
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// Doppler effect
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// Fd=(C/(C+Vr))*F
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double radial_velocity = (d_signal_carrier_freq + d_acq_carrier_doppler_hz) / d_signal_carrier_freq;
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// new chip and prn sequence periods based on acq Doppler
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d_code_freq_chips = radial_velocity * d_code_chip_rate;
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d_code_phase_step_chips = static_cast<double>(d_code_freq_chips) / static_cast<double>(d_fs_in);
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double T_chip_mod_seconds = 1.0 / d_code_freq_chips;
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double T_prn_mod_seconds = T_chip_mod_seconds * static_cast<double>(d_code_length_chips);
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double T_prn_mod_samples = T_prn_mod_seconds * d_fs_in;
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d_current_prn_length_samples = round(T_prn_mod_samples);
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double T_prn_true_seconds = static_cast<double>(d_code_length_chips) / d_code_chip_rate;
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double T_prn_true_samples = T_prn_true_seconds * d_fs_in;
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double T_prn_diff_seconds = T_prn_true_seconds - T_prn_mod_seconds;
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double N_prn_diff = acq_trk_diff_seconds / T_prn_true_seconds;
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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);
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if (corrected_acq_phase_samples < 0.0)
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{
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corrected_acq_phase_samples += T_prn_mod_samples;
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}
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double delay_correction_samples = d_acq_code_phase_samples - corrected_acq_phase_samples;
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d_acq_code_phase_samples = corrected_acq_phase_samples;
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d_carrier_doppler_hz = d_acq_carrier_doppler_hz;
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d_carrier_phase_step_rad = GALILEO_TWO_PI * d_carrier_doppler_hz / d_fs_in;
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// DLL/PLL filter initialization
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d_carrier_loop_filter.initialize(); // initialize the carrier filter
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d_code_loop_filter.initialize(); // initialize the code filter
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if (d_track_pilot)
|
|
{
|
|
char pilot_signal[3] = "1C";
|
|
galileo_e1_code_gen_float_sampled(d_tracking_code, pilot_signal, false,
|
|
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, 0.0);
|
|
correlator_data_cpu.set_local_code_and_taps(d_code_length_chips, d_data_code, d_null_shift);
|
|
}
|
|
else
|
|
{
|
|
galileo_e1_code_gen_float_sampled(d_tracking_code, d_acquisition_gnss_synchro->Signal, false,
|
|
d_acquisition_gnss_synchro->PRN, Galileo_E1_CODE_CHIP_RATE_HZ, 0);
|
|
}
|
|
|
|
multicorrelator_cpu.set_local_code_and_taps(d_code_length_chips, d_tracking_code, d_local_code_shift_chips);
|
|
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;
|
|
d_rem_carr_phase_rad = 0.0;
|
|
d_rem_code_phase_chips = 0.0;
|
|
d_acc_carrier_phase_rad = 0.0;
|
|
|
|
d_code_phase_samples = d_acq_code_phase_samples;
|
|
|
|
// DEBUG OUTPUT
|
|
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;
|
|
|
|
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;
|
|
}
|
|
|
|
|
|
dll_pll_veml_tracking::~dll_pll_veml_tracking()
|
|
{
|
|
if (d_dump_file.is_open())
|
|
{
|
|
try
|
|
{
|
|
d_dump_file.close();
|
|
}
|
|
catch (const std::exception &ex)
|
|
{
|
|
LOG(WARNING) << "Exception in destructor " << ex.what();
|
|
}
|
|
}
|
|
if (d_dump)
|
|
{
|
|
if (d_channel == 0)
|
|
{
|
|
std::cout << "Writing .mat files ...";
|
|
}
|
|
save_matfile();
|
|
if (d_channel == 0)
|
|
{
|
|
std::cout << " done." << std::endl;
|
|
}
|
|
}
|
|
try
|
|
{
|
|
volk_gnsssdr_free(d_local_code_shift_chips);
|
|
volk_gnsssdr_free(d_correlator_outs);
|
|
volk_gnsssdr_free(d_tracking_code);
|
|
if (d_track_pilot)
|
|
{
|
|
volk_gnsssdr_free(d_Prompt_Data);
|
|
volk_gnsssdr_free(d_data_code);
|
|
correlator_data_cpu.free();
|
|
}
|
|
delete[] d_Prompt_buffer;
|
|
multicorrelator_cpu.free();
|
|
}
|
|
catch (const std::exception &ex)
|
|
{
|
|
LOG(WARNING) << "Exception in destructor " << ex.what();
|
|
}
|
|
}
|
|
|
|
|
|
bool dll_pll_veml_tracking::acquire_secondary()
|
|
{
|
|
//******* preamble correlation ********
|
|
int corr_value = 0;
|
|
for (unsigned int i = 0; i < d_secondary_code_length; i++)
|
|
{
|
|
if (d_Prompt_buffer_deque.at(i).real() < 0.0) // symbols clipping
|
|
{
|
|
if (d_secondary_code_string->at(i) == '0')
|
|
{
|
|
corr_value++;
|
|
}
|
|
else
|
|
{
|
|
corr_value--;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if (d_secondary_code_string->at(i) == '0')
|
|
{
|
|
corr_value--;
|
|
}
|
|
else
|
|
{
|
|
corr_value++;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (abs(corr_value) == d_secondary_code_length)
|
|
{
|
|
return true;
|
|
}
|
|
else
|
|
{
|
|
return false;
|
|
}
|
|
}
|
|
|
|
|
|
bool dll_pll_veml_tracking::cn0_and_tracking_lock_status()
|
|
{
|
|
// ####### CN0 ESTIMATION AND LOCK DETECTORS ######
|
|
if (d_cn0_estimation_counter < DLL_PLL_CN0_ESTIMATION_SAMPLES)
|
|
{
|
|
// fill buffer with prompt correlator output values
|
|
d_Prompt_buffer[d_cn0_estimation_counter] = d_P_accu;
|
|
d_cn0_estimation_counter++;
|
|
return true;
|
|
}
|
|
else
|
|
{
|
|
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, 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
|
|
if (d_carrier_lock_test < d_carrier_lock_threshold or d_CN0_SNV_dB_Hz < DLL_PLL_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 > DLL_PLL_MAXIMUM_LOCK_FAIL_COUNTER)
|
|
{
|
|
std::cout << "Loss of lock in channel " << d_channel << "!" << std::endl;
|
|
LOG(INFO) << "Loss of lock in channel " << d_channel << "!";
|
|
this->message_port_pub(pmt::mp("events"), pmt::from_long(3)); // 3 -> loss of lock
|
|
d_carrier_lock_fail_counter = 0;
|
|
return false;
|
|
}
|
|
else
|
|
{
|
|
return true;
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
// correlation requires:
|
|
// - updated remnant carrier phase in radians (rem_carr_phase_rad)
|
|
// - updated remnant code phase in samples (d_rem_code_phase_samples)
|
|
// - d_code_freq_chips
|
|
// - d_carrier_doppler_hz
|
|
void dll_pll_veml_tracking::do_correlation_step(const gr_complex *input_samples)
|
|
{
|
|
// ################# CARRIER WIPEOFF AND CORRELATORS ##############################
|
|
// perform carrier wipe-off and compute Early, Prompt and Late correlation
|
|
multicorrelator_cpu.set_input_output_vectors(d_correlator_outs, input_samples);
|
|
multicorrelator_cpu.Carrier_wipeoff_multicorrelator_resampler(
|
|
d_rem_carr_phase_rad,
|
|
d_carrier_phase_step_rad,
|
|
d_rem_code_phase_chips,
|
|
d_code_phase_step_chips,
|
|
d_correlation_length_samples);
|
|
|
|
// DATA CORRELATOR (if tracking tracks the pilot signal)
|
|
if (d_track_pilot)
|
|
{
|
|
correlator_data_cpu.set_input_output_vectors(d_Prompt_Data, input_samples);
|
|
correlator_data_cpu.Carrier_wipeoff_multicorrelator_resampler(
|
|
d_rem_carr_phase_rad,
|
|
d_carrier_phase_step_rad,
|
|
d_rem_code_phase_chips,
|
|
d_code_phase_step_chips,
|
|
d_correlation_length_samples);
|
|
}
|
|
}
|
|
|
|
|
|
void dll_pll_veml_tracking::run_dll_pll(bool disable_costas_loop)
|
|
{
|
|
// ################## PLL ##########################################################
|
|
// PLL discriminator
|
|
if (disable_costas_loop == true)
|
|
{
|
|
// Secondary code acquired. No symbols transition should be present in the signal
|
|
d_carr_error_hz = pll_four_quadrant_atan(d_P_accu) / GALILEO_TWO_PI;
|
|
}
|
|
else
|
|
{
|
|
// Costas loop discriminator, insensitive to 180 deg phase transitions
|
|
d_carr_error_hz = pll_cloop_two_quadrant_atan(d_P_accu) / GALILEO_TWO_PI;
|
|
}
|
|
|
|
// Carrier discriminator filter
|
|
d_carr_error_filt_hz = d_carrier_loop_filter.get_carrier_nco(d_carr_error_hz);
|
|
// 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 = (1.0 + d_carrier_doppler_hz / d_signal_carrier_freq) * d_code_chip_rate;
|
|
|
|
// ################## DLL ##########################################################
|
|
// DLL discriminator
|
|
d_code_error_chips = dll_nc_vemlp_normalized(d_VE_accu, d_E_accu, d_L_accu, d_VL_accu); // [chips/Ti]
|
|
// Code discriminator filter
|
|
d_code_error_filt_chips = d_code_loop_filter.get_code_nco(d_code_error_chips); // [chips/second]
|
|
}
|
|
|
|
|
|
void dll_pll_veml_tracking::clear_tracking_vars()
|
|
{
|
|
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;
|
|
d_code_error_filt_chips = 0.0;
|
|
d_current_symbol = 0;
|
|
}
|
|
|
|
|
|
void dll_pll_veml_tracking::log_data()
|
|
{
|
|
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 = 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);
|
|
|
|
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
|
|
tmp_float = d_acc_carrier_phase_rad;
|
|
d_dump_file.write(reinterpret_cast<char *>(&tmp_float), sizeof(float));
|
|
// carrier and code frequency
|
|
tmp_float = d_carrier_doppler_hz;
|
|
d_dump_file.write(reinterpret_cast<char *>(&tmp_float), sizeof(float));
|
|
tmp_float = d_code_freq_chips;
|
|
d_dump_file.write(reinterpret_cast<char *>(&tmp_float), sizeof(float));
|
|
// PLL commands
|
|
tmp_float = d_carr_error_hz;
|
|
d_dump_file.write(reinterpret_cast<char *>(&tmp_float), sizeof(float));
|
|
tmp_float = d_carr_error_filt_hz;
|
|
d_dump_file.write(reinterpret_cast<char *>(&tmp_float), sizeof(float));
|
|
// DLL commands
|
|
tmp_float = d_code_error_chips;
|
|
d_dump_file.write(reinterpret_cast<char *>(&tmp_float), sizeof(float));
|
|
tmp_float = d_code_error_filt_chips;
|
|
d_dump_file.write(reinterpret_cast<char *>(&tmp_float), sizeof(float));
|
|
// CN0 and carrier lock test
|
|
tmp_float = d_CN0_SNV_dB_Hz;
|
|
d_dump_file.write(reinterpret_cast<char *>(&tmp_float), sizeof(float));
|
|
tmp_float = d_carrier_lock_test;
|
|
d_dump_file.write(reinterpret_cast<char *>(&tmp_float), 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));
|
|
// PRN
|
|
unsigned int prn_ = d_acquisition_gnss_synchro->PRN;
|
|
d_dump_file.write(reinterpret_cast<char *>(&prn_), sizeof(unsigned int));
|
|
}
|
|
catch (const std::ifstream::failure &e)
|
|
{
|
|
LOG(WARNING) << "Exception writing trk dump file " << e.what();
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
int dll_pll_veml_tracking::general_work(int noutput_items __attribute__((unused)), gr_vector_int &ninput_items __attribute__((unused)),
|
|
gr_vector_const_void_star &input_items, gr_vector_void_star &output_items)
|
|
{
|
|
gr::thread::scoped_lock l(d_setlock);
|
|
const gr_complex *in = reinterpret_cast<const gr_complex *>(input_items[0]);
|
|
Gnss_Synchro **out = reinterpret_cast<Gnss_Synchro **>(&output_items[0]);
|
|
Gnss_Synchro current_synchro_data = Gnss_Synchro();
|
|
|
|
switch (d_state)
|
|
{
|
|
case 0: // Standby - Pass Through
|
|
{
|
|
break;
|
|
}
|
|
case 1: // Pull-in
|
|
{
|
|
// Signal alignment (skip samples until the incoming signal is aligned with local replica)
|
|
// Fill the acquisition data
|
|
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
|
|
{
|
|
// 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 / 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
|
|
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;
|
|
|
|
// 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
|
|
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) / 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 = 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 * 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 ##########
|
|
if (d_track_pilot)
|
|
{
|
|
current_synchro_data.Prompt_I = static_cast<double>((*d_Prompt_Data).real());
|
|
current_synchro_data.Prompt_Q = static_cast<double>((*d_Prompt_Data).imag());
|
|
}
|
|
else
|
|
{
|
|
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.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
|
|
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 = d_correlation_length_ms;
|
|
|
|
// enable write dump file this cycle (valid DLL/PLL cycle)
|
|
log_data();
|
|
|
|
if (d_enable_extended_integration)
|
|
{
|
|
// ####### SECONDARY CODE LOCK #####
|
|
d_Prompt_buffer_deque.push_back(*d_Prompt);
|
|
if (d_Prompt_buffer_deque.size() == d_secondary_code_length)
|
|
{
|
|
if (acquire_secondary())
|
|
{
|
|
d_extend_correlation_symbols_count = 0;
|
|
// reset extended correlator
|
|
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 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[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, d_acquisition_gnss_synchro->PRN);
|
|
std::cout << "Enabled " << d_extend_correlation_symbols << " [symbols] extended correlator for CH "
|
|
<< d_channel
|
|
<< " : Satellite " << Gnss_Satellite(systemName, d_acquisition_gnss_synchro->PRN) << std::endl;
|
|
|
|
// UPDATE INTEGRATION TIME
|
|
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);
|
|
|
|
d_state = 3; // next state is the extended correlator integrator
|
|
}
|
|
|
|
d_Prompt_buffer_deque.pop_front();
|
|
}
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
case 3: // coherent integration (correlation time extension)
|
|
{
|
|
// 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 / 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 (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;
|
|
}
|
|
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_current_symbol++;
|
|
// secondary code roll-up
|
|
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
|
|
// Compute the next buffer length based in the new period of the PRN sequence and the code phase error estimation
|
|
|
|
// ################## 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) / 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) / 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 * 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 = 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.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 - 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 = d_correlation_length_ms;
|
|
|
|
d_extend_correlation_symbols_count++;
|
|
if (d_extend_correlation_symbols_count >= (d_extend_correlation_symbols - 1))
|
|
{
|
|
d_extend_correlation_symbols_count = 0;
|
|
d_state = 4;
|
|
}
|
|
break;
|
|
}
|
|
case 4: // narrow tracking
|
|
{
|
|
// Fill the acquisition data
|
|
current_synchro_data = *d_acquisition_gnss_synchro;
|
|
// perform a correlation step
|
|
do_correlation_step(in);
|
|
|
|
// correct the integration using the current symbol
|
|
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;
|
|
}
|
|
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_current_symbol++;
|
|
// secondary code roll-up
|
|
d_current_symbol %= d_secondary_code_length;
|
|
|
|
// check lock status
|
|
if (!cn0_and_tracking_lock_status())
|
|
{
|
|
clear_tracking_vars();
|
|
d_state = 0; // loss-of-lock detected
|
|
}
|
|
else
|
|
{
|
|
run_dll_pll(true); // Costas loop disabled, use four quadrant atan
|
|
|
|
// ################## 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) / 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) / 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 = 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 * 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.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 - 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 = 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, 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
|
|
}
|
|
}
|
|
}
|
|
|
|
//assign the GNURadio block output data
|
|
// current_synchro_data.System = {'E'};
|
|
// std::string str_aux = "1B";
|
|
// 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);
|
|
|
|
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
|
|
{
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
|
|
int dll_pll_veml_tracking::save_matfile()
|
|
{
|
|
// READ DUMP FILE
|
|
std::ifstream::pos_type size;
|
|
int number_of_double_vars = 1;
|
|
int number_of_float_vars = 17;
|
|
int epoch_size_bytes = sizeof(unsigned long int) + sizeof(double) * number_of_double_vars +
|
|
sizeof(float) * number_of_float_vars + sizeof(unsigned int);
|
|
std::ifstream dump_file;
|
|
dump_file.exceptions(std::ifstream::failbit | std::ifstream::badbit);
|
|
try
|
|
{
|
|
dump_file.open(d_dump_filename.c_str(), std::ios::binary | std::ios::ate);
|
|
}
|
|
catch (const std::ifstream::failure &e)
|
|
{
|
|
std::cerr << "Problem opening dump file:" << e.what() << std::endl;
|
|
return 1;
|
|
}
|
|
// count number of epochs and rewind
|
|
long int num_epoch = 0;
|
|
if (dump_file.is_open())
|
|
{
|
|
size = dump_file.tellg();
|
|
num_epoch = static_cast<long int>(size) / static_cast<long int>(epoch_size_bytes);
|
|
dump_file.seekg(0, std::ios::beg);
|
|
}
|
|
else
|
|
{
|
|
return 1;
|
|
}
|
|
float *abs_VE = new float[num_epoch];
|
|
float *abs_E = new float[num_epoch];
|
|
float *abs_P = new float[num_epoch];
|
|
float *abs_L = new float[num_epoch];
|
|
float *abs_VL = new float[num_epoch];
|
|
float *Prompt_I = new float[num_epoch];
|
|
float *Prompt_Q = new float[num_epoch];
|
|
unsigned long int *PRN_start_sample_count = new unsigned long int[num_epoch];
|
|
float *acc_carrier_phase_rad = new float[num_epoch];
|
|
float *carrier_doppler_hz = new float[num_epoch];
|
|
float *code_freq_chips = new float[num_epoch];
|
|
float *carr_error_hz = new float[num_epoch];
|
|
float *carr_error_filt_hz = new float[num_epoch];
|
|
float *code_error_chips = new float[num_epoch];
|
|
float *code_error_filt_chips = new float[num_epoch];
|
|
float *CN0_SNV_dB_Hz = new float[num_epoch];
|
|
float *carrier_lock_test = new float[num_epoch];
|
|
float *aux1 = new float[num_epoch];
|
|
double *aux2 = new double[num_epoch];
|
|
unsigned int *PRN = new unsigned int[num_epoch];
|
|
|
|
try
|
|
{
|
|
if (dump_file.is_open())
|
|
{
|
|
for (long int i = 0; i < num_epoch; i++)
|
|
{
|
|
dump_file.read(reinterpret_cast<char *>(&abs_VE[i]), sizeof(float));
|
|
dump_file.read(reinterpret_cast<char *>(&abs_E[i]), sizeof(float));
|
|
dump_file.read(reinterpret_cast<char *>(&abs_P[i]), sizeof(float));
|
|
dump_file.read(reinterpret_cast<char *>(&abs_L[i]), sizeof(float));
|
|
dump_file.read(reinterpret_cast<char *>(&abs_VL[i]), sizeof(float));
|
|
dump_file.read(reinterpret_cast<char *>(&Prompt_I[i]), sizeof(float));
|
|
dump_file.read(reinterpret_cast<char *>(&Prompt_Q[i]), sizeof(float));
|
|
dump_file.read(reinterpret_cast<char *>(&PRN_start_sample_count[i]), sizeof(unsigned long int));
|
|
dump_file.read(reinterpret_cast<char *>(&acc_carrier_phase_rad[i]), sizeof(float));
|
|
dump_file.read(reinterpret_cast<char *>(&carrier_doppler_hz[i]), sizeof(float));
|
|
dump_file.read(reinterpret_cast<char *>(&code_freq_chips[i]), sizeof(float));
|
|
dump_file.read(reinterpret_cast<char *>(&carr_error_hz[i]), sizeof(float));
|
|
dump_file.read(reinterpret_cast<char *>(&carr_error_filt_hz[i]), sizeof(float));
|
|
dump_file.read(reinterpret_cast<char *>(&code_error_chips[i]), sizeof(float));
|
|
dump_file.read(reinterpret_cast<char *>(&code_error_filt_chips[i]), sizeof(float));
|
|
dump_file.read(reinterpret_cast<char *>(&CN0_SNV_dB_Hz[i]), sizeof(float));
|
|
dump_file.read(reinterpret_cast<char *>(&carrier_lock_test[i]), sizeof(float));
|
|
dump_file.read(reinterpret_cast<char *>(&aux1[i]), sizeof(float));
|
|
dump_file.read(reinterpret_cast<char *>(&aux2[i]), sizeof(double));
|
|
dump_file.read(reinterpret_cast<char *>(&PRN[i]), sizeof(unsigned int));
|
|
}
|
|
}
|
|
dump_file.close();
|
|
}
|
|
catch (const std::ifstream::failure &e)
|
|
{
|
|
std::cerr << "Problem reading dump file:" << e.what() << std::endl;
|
|
delete[] abs_VE;
|
|
delete[] abs_E;
|
|
delete[] abs_P;
|
|
delete[] abs_L;
|
|
delete[] abs_VL;
|
|
delete[] Prompt_I;
|
|
delete[] Prompt_Q;
|
|
delete[] PRN_start_sample_count;
|
|
delete[] acc_carrier_phase_rad;
|
|
delete[] carrier_doppler_hz;
|
|
delete[] code_freq_chips;
|
|
delete[] carr_error_hz;
|
|
delete[] carr_error_filt_hz;
|
|
delete[] code_error_chips;
|
|
delete[] code_error_filt_chips;
|
|
delete[] CN0_SNV_dB_Hz;
|
|
delete[] carrier_lock_test;
|
|
delete[] aux1;
|
|
delete[] aux2;
|
|
delete[] PRN;
|
|
return 1;
|
|
}
|
|
|
|
// WRITE MAT FILE
|
|
mat_t *matfp;
|
|
matvar_t *matvar;
|
|
std::string filename = d_dump_filename;
|
|
filename.erase(filename.length() - 4, 4);
|
|
filename.append(".mat");
|
|
matfp = Mat_CreateVer(filename.c_str(), NULL, MAT_FT_MAT73);
|
|
if (reinterpret_cast<long *>(matfp) != NULL)
|
|
{
|
|
size_t dims[2] = {1, static_cast<size_t>(num_epoch)};
|
|
matvar = Mat_VarCreate("abs_VE", MAT_C_SINGLE, MAT_T_SINGLE, 2, dims, abs_E, 0);
|
|
Mat_VarWrite(matfp, matvar, MAT_COMPRESSION_ZLIB); // or MAT_COMPRESSION_NONE
|
|
Mat_VarFree(matvar);
|
|
|
|
matvar = Mat_VarCreate("abs_E", MAT_C_SINGLE, MAT_T_SINGLE, 2, dims, abs_E, 0);
|
|
Mat_VarWrite(matfp, matvar, MAT_COMPRESSION_ZLIB); // or MAT_COMPRESSION_NONE
|
|
Mat_VarFree(matvar);
|
|
|
|
matvar = Mat_VarCreate("abs_P", MAT_C_SINGLE, MAT_T_SINGLE, 2, dims, abs_P, 0);
|
|
Mat_VarWrite(matfp, matvar, MAT_COMPRESSION_ZLIB); // or MAT_COMPRESSION_NONE
|
|
Mat_VarFree(matvar);
|
|
|
|
matvar = Mat_VarCreate("abs_L", MAT_C_SINGLE, MAT_T_SINGLE, 2, dims, abs_L, 0);
|
|
Mat_VarWrite(matfp, matvar, MAT_COMPRESSION_ZLIB); // or MAT_COMPRESSION_NONE
|
|
Mat_VarFree(matvar);
|
|
|
|
matvar = Mat_VarCreate("abs_VL", MAT_C_SINGLE, MAT_T_SINGLE, 2, dims, abs_E, 0);
|
|
Mat_VarWrite(matfp, matvar, MAT_COMPRESSION_ZLIB); // or MAT_COMPRESSION_NONE
|
|
Mat_VarFree(matvar);
|
|
|
|
matvar = Mat_VarCreate("Prompt_I", MAT_C_SINGLE, MAT_T_SINGLE, 2, dims, Prompt_I, 0);
|
|
Mat_VarWrite(matfp, matvar, MAT_COMPRESSION_ZLIB); // or MAT_COMPRESSION_NONE
|
|
Mat_VarFree(matvar);
|
|
|
|
matvar = Mat_VarCreate("Prompt_Q", MAT_C_SINGLE, MAT_T_SINGLE, 2, dims, Prompt_Q, 0);
|
|
Mat_VarWrite(matfp, matvar, MAT_COMPRESSION_ZLIB); // or MAT_COMPRESSION_NONE
|
|
Mat_VarFree(matvar);
|
|
|
|
matvar = Mat_VarCreate("PRN_start_sample_count", MAT_C_UINT64, MAT_T_UINT64, 2, dims, PRN_start_sample_count, 0);
|
|
Mat_VarWrite(matfp, matvar, MAT_COMPRESSION_ZLIB); // or MAT_COMPRESSION_NONE
|
|
Mat_VarFree(matvar);
|
|
|
|
matvar = Mat_VarCreate("acc_carrier_phase_rad", MAT_C_SINGLE, MAT_T_SINGLE, 2, dims, acc_carrier_phase_rad, 0);
|
|
Mat_VarWrite(matfp, matvar, MAT_COMPRESSION_ZLIB); // or MAT_COMPRESSION_NONE
|
|
Mat_VarFree(matvar);
|
|
|
|
matvar = Mat_VarCreate("carrier_doppler_hz", MAT_C_SINGLE, MAT_T_SINGLE, 2, dims, carrier_doppler_hz, 0);
|
|
Mat_VarWrite(matfp, matvar, MAT_COMPRESSION_ZLIB); // or MAT_COMPRESSION_NONE
|
|
Mat_VarFree(matvar);
|
|
|
|
matvar = Mat_VarCreate("code_freq_chips", MAT_C_SINGLE, MAT_T_SINGLE, 2, dims, code_freq_chips, 0);
|
|
Mat_VarWrite(matfp, matvar, MAT_COMPRESSION_ZLIB); // or MAT_COMPRESSION_NONE
|
|
Mat_VarFree(matvar);
|
|
|
|
matvar = Mat_VarCreate("carr_error_hz", MAT_C_SINGLE, MAT_T_SINGLE, 2, dims, carr_error_hz, 0);
|
|
Mat_VarWrite(matfp, matvar, MAT_COMPRESSION_ZLIB); // or MAT_COMPRESSION_NONE
|
|
Mat_VarFree(matvar);
|
|
|
|
matvar = Mat_VarCreate("carr_error_filt_hz", MAT_C_SINGLE, MAT_T_SINGLE, 2, dims, carr_error_filt_hz, 0);
|
|
Mat_VarWrite(matfp, matvar, MAT_COMPRESSION_ZLIB); // or MAT_COMPRESSION_NONE
|
|
Mat_VarFree(matvar);
|
|
|
|
matvar = Mat_VarCreate("code_error_chips", MAT_C_SINGLE, MAT_T_SINGLE, 2, dims, code_error_chips, 0);
|
|
Mat_VarWrite(matfp, matvar, MAT_COMPRESSION_ZLIB); // or MAT_COMPRESSION_NONE
|
|
Mat_VarFree(matvar);
|
|
|
|
matvar = Mat_VarCreate("code_error_filt_chips", MAT_C_SINGLE, MAT_T_SINGLE, 2, dims, code_error_filt_chips, 0);
|
|
Mat_VarWrite(matfp, matvar, MAT_COMPRESSION_ZLIB); // or MAT_COMPRESSION_NONE
|
|
Mat_VarFree(matvar);
|
|
|
|
matvar = Mat_VarCreate("CN0_SNV_dB_Hz", MAT_C_SINGLE, MAT_T_SINGLE, 2, dims, CN0_SNV_dB_Hz, 0);
|
|
Mat_VarWrite(matfp, matvar, MAT_COMPRESSION_ZLIB); // or MAT_COMPRESSION_NONE
|
|
Mat_VarFree(matvar);
|
|
|
|
matvar = Mat_VarCreate("carrier_lock_test", MAT_C_SINGLE, MAT_T_SINGLE, 2, dims, carrier_lock_test, 0);
|
|
Mat_VarWrite(matfp, matvar, MAT_COMPRESSION_ZLIB); // or MAT_COMPRESSION_NONE
|
|
Mat_VarFree(matvar);
|
|
|
|
matvar = Mat_VarCreate("aux1", MAT_C_SINGLE, MAT_T_SINGLE, 2, dims, aux1, 0);
|
|
Mat_VarWrite(matfp, matvar, MAT_COMPRESSION_ZLIB); // or MAT_COMPRESSION_NONE
|
|
Mat_VarFree(matvar);
|
|
|
|
matvar = Mat_VarCreate("aux2", MAT_C_DOUBLE, MAT_T_DOUBLE, 2, dims, aux2, 0);
|
|
Mat_VarWrite(matfp, matvar, MAT_COMPRESSION_ZLIB); // or MAT_COMPRESSION_NONE
|
|
Mat_VarFree(matvar);
|
|
|
|
matvar = Mat_VarCreate("PRN", MAT_C_UINT32, MAT_T_UINT32, 2, dims, PRN, 0);
|
|
Mat_VarWrite(matfp, matvar, MAT_COMPRESSION_ZLIB); // or MAT_COMPRESSION_NONE
|
|
Mat_VarFree(matvar);
|
|
}
|
|
Mat_Close(matfp);
|
|
delete[] abs_VE;
|
|
delete[] abs_E;
|
|
delete[] abs_P;
|
|
delete[] abs_L;
|
|
delete[] abs_VL;
|
|
delete[] Prompt_I;
|
|
delete[] Prompt_Q;
|
|
delete[] PRN_start_sample_count;
|
|
delete[] acc_carrier_phase_rad;
|
|
delete[] carrier_doppler_hz;
|
|
delete[] code_freq_chips;
|
|
delete[] carr_error_hz;
|
|
delete[] carr_error_filt_hz;
|
|
delete[] code_error_chips;
|
|
delete[] code_error_filt_chips;
|
|
delete[] CN0_SNV_dB_Hz;
|
|
delete[] carrier_lock_test;
|
|
delete[] aux1;
|
|
delete[] aux2;
|
|
delete[] PRN;
|
|
return 0;
|
|
}
|
|
|
|
|
|
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)
|
|
{
|
|
if (!d_dump_file.is_open())
|
|
{
|
|
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 (const std::ifstream::failure &e)
|
|
{
|
|
LOG(WARNING) << "channel " << d_channel << " Exception opening trk dump file " << e.what();
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
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;
|
|
}
|