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https://github.com/gnss-sdr/gnss-sdr
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git-svn-id: https://svn.code.sf.net/p/gnss-sdr/code/trunk@127 64b25241-fba3-4117-9849-534c7e92360d
639 lines
26 KiB
C++
639 lines
26 KiB
C++
/*!
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* \file gps_l1_ca_dll_fll_pll_tracking_cc.cc
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* \brief Implementation of a code DLL + carrier FLL/PLL tracking block
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* \author Javier Arribas, 2011. jarribas(at)cttc.es
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*
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* This file implements the code Delay Locked Loop (DLL) + carrier
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* Phase Locked Loop (PLL) helped with a carrier Frequency Locked Loop (FLL)
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* according to the algorithms described in:
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* E.D. Kaplan and C. Hegarty, Understanding GPS. Principles and
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* Applications, Second Edition, Artech House Publishers, 2005.
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*
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* -------------------------------------------------------------------------
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*
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* Copyright (C) 2010-2011 (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 "gps_l1_ca_dll_fll_pll_tracking_cc.h"
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#include "gps_sdr_signal_processing.h"
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#include "GPS_L1_CA.h"
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#include "tracking_discriminators.h"
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#include "CN_estimators.h"
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#include "tracking_FLL_PLL_filter.h"
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#include "control_message_factory.h"
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#include <boost/lexical_cast.hpp>
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#include <iostream>
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#include <sstream>
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#include <cmath>
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#include "math.h"
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#include <gnuradio/gr_io_signature.h>
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#include <glog/log_severity.h>
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#include <glog/logging.h>
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/*!
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* \todo Include in definition header file
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*/
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#define CN0_ESTIMATION_SAMPLES 10
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#define MINIMUM_VALID_CN0 25
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#define MAXIMUM_LOCK_FAIL_COUNTER 200
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using google::LogMessage;
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gps_l1_ca_dll_fll_pll_tracking_cc_sptr
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gps_l1_ca_dll_fll_pll_make_tracking_cc(unsigned int satellite, long if_freq, long fs_in, unsigned
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int vector_length, gr_msg_queue_sptr queue, bool dump, std::string dump_filename, int order,
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float fll_bw_hz, float pll_bw_hz, float dll_bw_hz, float early_late_space_chips)
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{
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return gps_l1_ca_dll_fll_pll_tracking_cc_sptr(new Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc(satellite, if_freq,
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fs_in, vector_length, queue, dump, dump_filename, order, fll_bw_hz, pll_bw_hz,dll_bw_hz,
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early_late_space_chips));
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}
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void Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::forecast (int noutput_items, gr_vector_int &ninput_items_required)
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{
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ninput_items_required[0] = d_vector_length*2; //set the required available samples in each call
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}
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Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc(unsigned int satellite,
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long if_freq, long fs_in, unsigned int vector_length, gr_msg_queue_sptr queue, bool dump,
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std::string dump_filename, int order, float fll_bw_hz, float pll_bw_hz, float dll_bw_hz,
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float early_late_space_chips) :
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gr_block ("Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc", gr_make_io_signature (1, 1, sizeof(gr_complex)),
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gr_make_io_signature(5, 5, sizeof(double)))
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{
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//gr_sync_decimator ("gps_l1_ca_dll_pll_tracking_cc", gr_make_io_signature (1, 1, sizeof(gr_complex)),
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// gr_make_io_signature(3, 3, sizeof(float)),vector_length) {
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// initialize internal vars
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d_queue = queue;
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d_dump = dump;
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d_satellite = satellite;
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d_if_freq = if_freq;
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d_fs_in = fs_in;
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d_vector_length = vector_length;
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d_early_late_spc_chips = early_late_space_chips; // Define early-late offset (in chips)
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d_dump_filename=dump_filename;
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// Initialize tracking variables ==========================================
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d_carrier_loop_filter.set_params(fll_bw_hz,pll_bw_hz,order);
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// Get space for a vector with the C/A code replica sampled 1x/chip
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d_ca_code = new gr_complex[(int)GPS_L1_CA_CODE_LENGTH_CHIPS+2];
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// Get space for the resampled early / prompt / late local replicas
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d_early_code = new gr_complex[d_vector_length*2];
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d_prompt_code = new gr_complex[d_vector_length*2];
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d_late_code = new gr_complex[d_vector_length*2];
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// space for carrier wipeoff LO vector
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d_carr_sign = new gr_complex[d_vector_length*2];
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// sample synchronization
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d_sample_counter = 0;
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d_sample_counter_seconds = 0;
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d_acq_sample_stamp = 0;
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d_last_seg = 0;// this is for debug output only
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d_enable_tracking = false;
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d_current_prn_length_samples = (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[CN0_ESTIMATION_SAMPLES];
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d_carrier_lock_test = 1;
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d_CN0_SNV_dB_Hz = 0;
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d_carrier_lock_fail_counter = 0;
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d_carrier_lock_threshold = 5;
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}
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void Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::start_tracking()
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{
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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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unsigned long int acq_trk_diff_samples;
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float acq_trk_diff_seconds;
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acq_trk_diff_samples = d_sample_counter - d_acq_sample_stamp;//-d_vector_length;
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//std::cout<<"acq_trk_diff_samples="<<acq_trk_diff_samples<<"\r\n";
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acq_trk_diff_seconds = (float)acq_trk_diff_samples / (float)d_fs_in;
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//doppler effect
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// Fd=(C/(C+Vr))*F
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float radial_velocity;
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radial_velocity = (GPS_L1_FREQ_HZ + d_acq_carrier_doppler_hz) / GPS_L1_FREQ_HZ;
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// new chip and prn sequence periods based on acq Doppler
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float T_chip_mod_seconds;
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float T_prn_mod_seconds;
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float T_prn_mod_samples;
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d_code_freq_hz = radial_velocity * GPS_L1_CA_CODE_RATE_HZ;
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T_chip_mod_seconds = 1 / d_code_freq_hz;
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T_prn_mod_seconds = T_chip_mod_seconds * GPS_L1_CA_CODE_LENGTH_CHIPS;
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T_prn_mod_samples = T_prn_mod_seconds * (float)d_fs_in;
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d_next_prn_length_samples = round(T_prn_mod_samples);
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float T_prn_true_seconds = GPS_L1_CA_CODE_LENGTH_CHIPS / GPS_L1_CA_CODE_RATE_HZ;
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float T_prn_true_samples = T_prn_true_seconds * (float)d_fs_in;
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float T_prn_diff_seconds;
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T_prn_diff_seconds = T_prn_true_seconds - T_prn_mod_seconds;
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float N_prn_diff;
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N_prn_diff = acq_trk_diff_seconds / T_prn_true_seconds;
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float corrected_acq_phase_samples, delay_correction_samples;
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corrected_acq_phase_samples = fmod((d_acq_code_phase_samples + T_prn_diff_seconds * N_prn_diff * (float)d_fs_in), T_prn_true_samples);
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if (corrected_acq_phase_samples < 0)
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{
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corrected_acq_phase_samples = T_prn_mod_samples + corrected_acq_phase_samples;
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}
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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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// DLL/PLL filter initialization
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d_carrier_loop_filter.initialize(d_acq_carrier_doppler_hz);
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d_FLL_wait = 1;
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// generate local reference ALWAYS starting at chip 1 (1 sample per chip)
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code_gen_conplex(&d_ca_code[1], d_satellite, 0);
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d_ca_code[0] = d_ca_code[(int)GPS_L1_CA_CODE_LENGTH_CHIPS];
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d_ca_code[(int)GPS_L1_CA_CODE_LENGTH_CHIPS + 1] = d_ca_code[1];
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d_carrier_lock_fail_counter = 0;
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d_Prompt_prev = 0;
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d_rem_code_phase_samples = 0;
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d_rem_carr_phase = 0;
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d_FLL_discriminator_hz = 0;
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d_rem_code_phase_samples = 0;
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d_next_rem_code_phase_samples = 0;
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d_acc_carrier_phase_rad = 0;
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d_code_phase_samples = d_acq_code_phase_samples;
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// DEBUG OUTPUT
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std::cout << "Tracking start on channel " << d_channel << " for satellite ID* " << this->d_satellite << std::endl;
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DLOG(INFO) << "Start tracking for satellite " << this->d_satellite << " received ";
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// enable tracking
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d_pull_in = true;
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d_enable_tracking = true;
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std::cout << "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 << std::endl;
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}
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void Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::update_local_code()
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{
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float tcode_chips;
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float rem_code_phase_chips;
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float code_phase_step_chips;
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int associated_chip_index;
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int code_length_chips = (int)GPS_L1_CA_CODE_LENGTH_CHIPS;
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code_phase_step_chips = d_code_freq_hz / ((float)d_fs_in);
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rem_code_phase_chips = d_rem_code_phase_samples * (d_code_freq_hz / d_fs_in);
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// unified loop for E, P, L code vectors
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tcode_chips = -rem_code_phase_chips;
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for (int i=0; i<d_current_prn_length_samples; i++)
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{
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associated_chip_index = 1 + round(fmod(tcode_chips - d_early_late_spc_chips, code_length_chips));
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d_early_code[i] = d_ca_code[associated_chip_index];
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associated_chip_index = 1 + round(fmod(tcode_chips, code_length_chips));
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d_prompt_code[i] = d_ca_code[associated_chip_index];
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associated_chip_index = 1 + round(fmod(tcode_chips + d_early_late_spc_chips, code_length_chips));
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d_late_code[i] = d_ca_code[associated_chip_index];
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tcode_chips = tcode_chips+code_phase_step_chips;
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}
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//d_code_phase_samples=d_code_phase_samples+(float)d_fs_in*GPS_L1_CA_CODE_LENGTH_CHIPS*(1/d_code_freq_hz-1/GPS_L1_CA_CODE_RATE_HZ);
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}
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void Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::update_local_carrier()
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{
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float phase, phase_step;
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phase_step = (float)TWO_PI * d_carrier_doppler_hz / (float)d_fs_in;
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phase = d_rem_carr_phase;
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for(int i = 0; i < d_current_prn_length_samples; i++)
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{
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d_carr_sign[i] = gr_complex(cos(phase), sin(phase));
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phase += phase_step;
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}
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d_rem_carr_phase = fmod(phase, TWO_PI);
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d_acc_carrier_phase_rad = d_acc_carrier_phase_rad + d_rem_carr_phase;
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}
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Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::~Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc()
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{
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d_dump_file.close();
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delete[] d_ca_code;
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delete[] d_early_code;
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delete[] d_prompt_code;
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delete[] d_late_code;
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delete[] d_carr_sign;
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delete[] d_Prompt_buffer;
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}
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/* Tracking signal processing
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* Notice that this is a class derived from gr_sync_decimator, so each of the ninput_items has vector_length samples
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*/
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int Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::general_work (int noutput_items, gr_vector_int &ninput_items,
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gr_vector_const_void_star &input_items, gr_vector_void_star &output_items)
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{
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// if ((unsigned int)ninput_items[0]<(d_vector_length*2))
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// {
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// std::cout<<"End of signal detected\r\n";
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// const int samples_available = ninput_items[0];
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// consume_each(samples_available);
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// return 0;
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// }
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// process vars
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float code_error_chips = 0;
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float correlation_time_s = 0;
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float PLL_discriminator_hz = 0;
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float carr_nco_hz = 0;
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d_Prompt_prev = d_Prompt; // for the FLL discriminator
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d_Early = gr_complex(0,0);
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d_Prompt = gr_complex(0,0);
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d_Late = gr_complex(0,0);
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if (d_enable_tracking == true)
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{
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/*
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* Receiver signal alignment
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*/
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if (d_pull_in == true)
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{
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int samples_offset;
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// 28/11/2011 ACQ to TRK transition BUG CORRECTION
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float acq_trk_shif_correction_samples;
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int acq_to_trk_delay_samples;
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acq_to_trk_delay_samples = d_sample_counter-d_acq_sample_stamp;
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acq_trk_shif_correction_samples = d_next_prn_length_samples - fmod((float)acq_to_trk_delay_samples, (float)d_next_prn_length_samples);
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//std::cout<<"acq_trk_shif_correction="<<acq_trk_shif_correction_samples<<"\r\n";
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samples_offset = round(d_acq_code_phase_samples + acq_trk_shif_correction_samples);
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// /todo: Check if the sample counter sent to the next block as a time reference should be incremented AFTER sended or BEFORE
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d_sample_counter_seconds = d_sample_counter_seconds + (((double)samples_offset)/(double)d_fs_in);
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d_sample_counter = d_sample_counter + samples_offset; //count for the processed samples
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d_pull_in = false;
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//std::cout<<" samples_offset="<<samples_offset<<"\r\n";
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consume_each(samples_offset); //shift input to perform alignement with local replica
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return 1;
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}
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// get the sample in and out pointers
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const gr_complex* in = (gr_complex*) input_items[0]; //block input samples pointer
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double **out = (double **) &output_items[0]; //block output streams pointer
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// check for samples consistency
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for(int i=0; i<d_current_prn_length_samples; i++)
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{
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if (std::isnan(in[i].real()) == true or std::isnan(in[i].imag()) == true)// or std::isinf(in[i].real())==true or std::isinf(in[i].imag())==true)
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{
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const int samples_available = ninput_items[0];
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d_sample_counter = d_sample_counter + samples_available;
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LOG_AT_LEVEL(WARNING) << "Detected NaN samples at sample number " << d_sample_counter;
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consume_each(samples_available);
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return 0;
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}
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}
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// Update the prn length based on code freq (variable) and
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// sampling frequency (fixed)
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// variable code PRN sample block size
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d_current_prn_length_samples = d_next_prn_length_samples;
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update_local_code();
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update_local_carrier();
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gr_complex bb_signal_sample(0,0);
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// perform Early, Prompt and Late correlation
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/*!
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* \todo Use SIMD-enabled correlators
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*/
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for(int i=0; i<d_current_prn_length_samples; i++)
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{
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//Perform the carrier wipe-off
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bb_signal_sample = in[i] * d_carr_sign[i];
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// Now get early, late, and prompt values for each
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d_Early += bb_signal_sample*d_early_code[i];
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d_Prompt += bb_signal_sample*d_prompt_code[i];
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d_Late += bb_signal_sample*d_late_code[i];
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}
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/*
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* DLL, FLL, and PLL discriminators
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*/
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// Compute DLL error
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code_error_chips = dll_nc_e_minus_l_normalized(d_Early,d_Late);
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//compute FLL error
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correlation_time_s = ((float)d_current_prn_length_samples)/(float)d_fs_in;
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if (d_FLL_wait == 1)
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{
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d_Prompt_prev = d_Prompt;
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d_FLL_wait = 0;
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}
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else
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{
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d_FLL_discriminator_hz = fll_four_quadrant_atan(d_Prompt_prev, d_Prompt, 0, correlation_time_s)/(float)TWO_PI;
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d_Prompt_prev = d_Prompt;
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d_FLL_wait = 1;
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}
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// Compute PLL error
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PLL_discriminator_hz = pll_cloop_two_quadrant_atan(d_Prompt)/(float)TWO_PI;
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/*!
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* \todo Update FLL assistance algorithm!
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*/
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if (((float)d_sample_counter - (float)d_acq_sample_stamp)/(float)d_fs_in>3)
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{
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d_FLL_discriminator_hz = 0; //disconnect the FLL after the initial lock
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}
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/*!
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* DLL and FLL+PLL filter and get current carrier Doppler and code frequency
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*/
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carr_nco_hz = d_carrier_loop_filter.get_carrier_error(d_FLL_discriminator_hz, PLL_discriminator_hz, correlation_time_s);
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d_carrier_doppler_hz = (float)d_if_freq + carr_nco_hz;
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d_code_freq_hz = GPS_L1_CA_CODE_RATE_HZ- (((d_carrier_doppler_hz - (float)d_if_freq)*GPS_L1_CA_CODE_RATE_HZ)/GPS_L1_FREQ_HZ) - code_error_chips;
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/*!
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* \todo Improve the lock detection algorithm!
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*/
|
|
// ####### 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;
|
|
d_CN0_SNV_dB_Hz=gps_l1_ca_CN0_SNV(d_Prompt_buffer, CN0_ESTIMATION_SAMPLES,d_fs_in);
|
|
d_carrier_lock_test=carrier_lock_detector(d_Prompt_buffer,CN0_ESTIMATION_SAMPLES);
|
|
// ###### TRACKING UNLOCK NOTIFICATION #####
|
|
int tracking_message;
|
|
if (d_carrier_lock_test < d_carrier_lock_threshold or d_carrier_lock_test > 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<<"Channel "<< d_channel << " loss of lock!" << std::endl;
|
|
tracking_message = 3; //loss of lock
|
|
d_channel_internal_queue->push(tracking_message);
|
|
d_carrier_lock_fail_counter = 0;
|
|
d_enable_tracking = false; // TODO: check if disabling tracking is consistent with the channel state machine
|
|
|
|
}
|
|
//std::cout<<"d_carrier_lock_fail_counter"<<d_carrier_lock_fail_counter<<"\r\n";
|
|
}
|
|
|
|
/*!
|
|
* \todo Output the CN0
|
|
*/
|
|
// ########### Output the tracking data to navigation and PVT ##########
|
|
// Output channel 0: Prompt correlator output Q
|
|
*out[0]=(double)d_Prompt.real();
|
|
// Output channel 1: Prompt correlator output I
|
|
*out[1]=(double)d_Prompt.imag();
|
|
// Output channel 2: PRN absolute delay [s]
|
|
*out[2]=d_sample_counter_seconds;
|
|
// Output channel 3: d_acc_carrier_phase_rad [rad]
|
|
*out[3]=(double)d_acc_carrier_phase_rad;
|
|
// Output channel 4: PRN code phase [s]
|
|
*out[4]=(double)d_code_phase_samples*(1/(float)d_fs_in);
|
|
|
|
// ########## DEBUG OUTPUT
|
|
/*!
|
|
* \todo The stop timer has to be moved to the signal source!
|
|
*/
|
|
// debug: Second counter in channel 0
|
|
if (d_channel == 0)
|
|
{
|
|
if (floor(d_sample_counter/d_fs_in) != d_last_seg)
|
|
{
|
|
d_last_seg = floor(d_sample_counter/d_fs_in);
|
|
std::cout << "Current input signal time=" << d_last_seg << " [s]" << std::endl;
|
|
std::cout << "Tracking CH "<< d_channel << " CN0=" << d_CN0_SNV_dB_Hz << " [dB-Hz]" <<std::endl;
|
|
//std::cout<<"TRK CH "<<d_channel<<" Carrier_lock_test="<<d_carrier_lock_test<< std::endl;
|
|
//if (d_last_seg==5) d_carrier_lock_fail_counter=500; //DEBUG: force unlock!
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if (floor(d_sample_counter/d_fs_in) != d_last_seg)
|
|
{
|
|
d_last_seg = floor(d_sample_counter/d_fs_in);
|
|
std::cout << "Tracking CH " << d_channel << " CN0=" << d_CN0_SNV_dB_Hz << " [dB-Hz]" << std::endl;
|
|
//std::cout<<"TRK CH "<<d_channel<<" Carrier_lock_test="<<d_carrier_lock_test<< std::endl;
|
|
}
|
|
}
|
|
|
|
//predict the next loop PRN period length prediction
|
|
float T_chip_seconds;
|
|
float T_prn_seconds;
|
|
float T_prn_samples;
|
|
float K_blk_samples;
|
|
T_chip_seconds = 1/d_code_freq_hz;
|
|
T_prn_seconds = T_chip_seconds*GPS_L1_CA_CODE_LENGTH_CHIPS;
|
|
T_prn_samples = T_prn_seconds*(float)d_fs_in;
|
|
d_rem_code_phase_samples = d_next_rem_code_phase_samples;
|
|
K_blk_samples = T_prn_samples+d_rem_code_phase_samples;
|
|
|
|
// Update the current PRN delay (code phase in samples)
|
|
float T_prn_true_seconds = GPS_L1_CA_CODE_LENGTH_CHIPS/GPS_L1_CA_CODE_RATE_HZ;
|
|
float T_prn_true_samples = T_prn_true_seconds*(float)d_fs_in;
|
|
d_code_phase_samples = d_code_phase_samples + T_prn_samples - T_prn_true_samples;
|
|
if (d_code_phase_samples < 0)
|
|
{
|
|
d_code_phase_samples = T_prn_true_samples + d_code_phase_samples;
|
|
}
|
|
d_code_phase_samples = fmod(d_code_phase_samples, T_prn_true_samples);
|
|
d_next_prn_length_samples = round(K_blk_samples);//round to a discrete samples
|
|
d_next_rem_code_phase_samples = K_blk_samples-d_next_prn_length_samples; //rounding error
|
|
}
|
|
else
|
|
{
|
|
double **out = (double **) &output_items[0]; //block output streams pointer
|
|
*out[0] = 0;
|
|
*out[1] = 0;
|
|
*out[2] = 0;
|
|
*out[3] = 0;
|
|
*out[4] = 0;
|
|
}
|
|
|
|
|
|
if(d_dump)
|
|
{
|
|
// MULTIPLEXED FILE RECORDING - Record results to file
|
|
float prompt_I;
|
|
float prompt_Q;
|
|
float tmp_E,tmp_P,tmp_L;
|
|
float tmp_float;
|
|
prompt_I = d_Prompt.imag();
|
|
prompt_Q = d_Prompt.real();
|
|
tmp_E=std::abs<float>(d_Early);
|
|
tmp_P=std::abs<float>(d_Prompt);
|
|
tmp_L=std::abs<float>(d_Late);
|
|
try
|
|
{
|
|
// EPR
|
|
d_dump_file.write((char*)&tmp_E, sizeof(float));
|
|
d_dump_file.write((char*)&tmp_P, sizeof(float));
|
|
d_dump_file.write((char*)&tmp_L, sizeof(float));
|
|
// PROMPT I and Q (to analyze navigation symbols)
|
|
d_dump_file.write((char*)&prompt_I, sizeof(float));
|
|
d_dump_file.write((char*)&prompt_Q, sizeof(float));
|
|
// PRN start sample stamp
|
|
//tmp_float=(float)d_sample_counter;
|
|
d_dump_file.write((char*)&d_sample_counter, sizeof(unsigned long int));
|
|
// accumulated carrier phase
|
|
d_dump_file.write((char*)&d_acc_carrier_phase_rad, sizeof(float));
|
|
|
|
// carrier and code frequency
|
|
d_dump_file.write((char*)&d_carrier_doppler_hz, sizeof(float));
|
|
d_dump_file.write((char*)&d_code_freq_hz, sizeof(float));
|
|
|
|
//PLL commands
|
|
d_dump_file.write((char*)&PLL_discriminator_hz, sizeof(float));
|
|
d_dump_file.write((char*)&carr_nco_hz, sizeof(float));
|
|
|
|
//DLL commands
|
|
d_dump_file.write((char*)&code_error_chips, sizeof(float));
|
|
d_dump_file.write((char*)&d_code_phase_samples, sizeof(float));
|
|
|
|
// CN0 and carrier lock test
|
|
d_dump_file.write((char*)&d_CN0_SNV_dB_Hz, sizeof(float));
|
|
d_dump_file.write((char*)&d_carrier_lock_test, sizeof(float));
|
|
|
|
// AUX vars (for debug purposes)
|
|
tmp_float = 0;
|
|
d_dump_file.write((char*)&tmp_float, sizeof(float));
|
|
d_dump_file.write((char*)&d_sample_counter_seconds, sizeof(double));
|
|
}
|
|
catch (std::ifstream::failure e)
|
|
{
|
|
std::cout << "Exception writing trk dump file "<<e.what()<<"\r\n";
|
|
}
|
|
}
|
|
consume_each(d_current_prn_length_samples); // this is necesary in gr_block derivates
|
|
d_sample_counter_seconds = d_sample_counter_seconds + (((double)d_current_prn_length_samples)/(double)d_fs_in);
|
|
d_sample_counter += d_current_prn_length_samples; //count for the processed samples
|
|
return 1; //output tracking result ALWAYS even in the case of d_enable_tracking==false
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
void Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::set_acq_code_phase(float code_phase)
|
|
{
|
|
d_acq_code_phase_samples = code_phase;
|
|
LOG_AT_LEVEL(INFO) << "Tracking code phase set to " << d_acq_code_phase_samples;
|
|
}
|
|
|
|
|
|
|
|
|
|
void Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::set_acq_doppler(float doppler)
|
|
{
|
|
d_acq_carrier_doppler_hz = doppler;
|
|
LOG_AT_LEVEL(INFO) << "Tracking carrier doppler set to " << d_acq_carrier_doppler_hz;
|
|
}
|
|
|
|
|
|
|
|
|
|
void Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::set_satellite(unsigned int satellite)
|
|
{
|
|
d_satellite = satellite;
|
|
LOG_AT_LEVEL(INFO) << "Tracking Satellite set to " << d_satellite;
|
|
}
|
|
|
|
|
|
|
|
void Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::set_channel(unsigned int channel)
|
|
{
|
|
d_channel = channel;
|
|
LOG_AT_LEVEL(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);
|
|
std::cout << "Tracking dump enabled on channel " << d_channel << " Log file: " << d_dump_filename.c_str() << std::endl;
|
|
}
|
|
catch (std::ifstream::failure e)
|
|
{
|
|
std::cout << "channel " << d_channel << " Exception opening trk dump file " << e.what() << std::endl;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
|
|
|
|
void Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::set_acq_sample_stamp(unsigned long int sample_stamp)
|
|
{
|
|
d_acq_sample_stamp = sample_stamp;
|
|
}
|
|
|
|
|
|
|
|
void Gps_L1_Ca_Dll_Fll_Pll_Tracking_cc::set_channel_queue(concurrent_queue<int> *channel_internal_queue)
|
|
{
|
|
d_channel_internal_queue = channel_internal_queue;
|
|
}
|