mirror of https://github.com/gnss-sdr/gnss-sdr
735 lines
31 KiB
C++
735 lines
31 KiB
C++
/*!
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* \file beidou_b3i_telemetry_decoder_gs.cc
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* \brief Implementation of an adapter of a BEIDOU B31 DNAV data decoder block
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* \author Damian Miralles, 2019. dmiralles2009(at)gmail.com
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*
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* -----------------------------------------------------------------------------
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*
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* GNSS-SDR is a Global Navigation Satellite System software-defined receiver.
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* This file is part of GNSS-SDR.
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*
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* Copyright (C) 2010-2020 (see AUTHORS file for a list of contributors)
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* SPDX-License-Identifier: GPL-3.0-or-later
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*
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* -----------------------------------------------------------------------------
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*/
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#include "beidou_b3i_telemetry_decoder_gs.h"
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#include "Beidou_B3I.h"
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#include "Beidou_DNAV.h"
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#include "beidou_dnav_almanac.h"
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#include "beidou_dnav_ephemeris.h"
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#include "beidou_dnav_iono.h"
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#include "beidou_dnav_utc_model.h"
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#include "display.h"
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#include "gnss_sdr_make_unique.h" // for std::make_unique in C++11
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#include "gnss_synchro.h"
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#include "tlm_utils.h"
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#include <glog/logging.h>
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#include <gnuradio/io_signature.h>
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#include <pmt/pmt.h> // for make_any
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#include <pmt/pmt_sugar.h> // for mp
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#include <cstddef> // for size_t
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#include <cstdlib> // for abs
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#include <exception> // for exception
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#include <iomanip> // for setprecision
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#include <iostream> // for cout
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#include <memory> // for shared_ptr, make_shared
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#define CRC_ERROR_LIMIT 8
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beidou_b3i_telemetry_decoder_gs_sptr
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beidou_b3i_make_telemetry_decoder_gs(const Gnss_Satellite &satellite,
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const Tlm_Conf &conf)
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{
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return beidou_b3i_telemetry_decoder_gs_sptr(new beidou_b3i_telemetry_decoder_gs(satellite, conf));
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}
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beidou_b3i_telemetry_decoder_gs::beidou_b3i_telemetry_decoder_gs(
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const Gnss_Satellite &satellite, const Tlm_Conf &conf)
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: gr::block("beidou_b3i_telemetry_decoder_gs",
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gr::io_signature::make(1, 1, sizeof(Gnss_Synchro)),
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gr::io_signature::make(1, 1, sizeof(Gnss_Synchro))),
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d_dump_filename(conf.dump_filename),
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d_sample_counter(0),
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d_preamble_index(0),
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d_required_symbols(BEIDOU_DNAV_SUBFRAME_SYMBOLS + BEIDOU_DNAV_PREAMBLE_LENGTH_SYMBOLS),
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d_stat(0),
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d_channel(0),
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d_CRC_error_counter(0),
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d_symbols_per_preamble(BEIDOU_DNAV_PREAMBLE_LENGTH_SYMBOLS),
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d_samples_per_preamble(BEIDOU_DNAV_PREAMBLE_LENGTH_SYMBOLS),
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d_preamble_period_samples(BEIDOU_DNAV_PREAMBLE_PERIOD_SYMBOLS),
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d_last_valid_preamble(0),
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d_symbol_duration_ms(BEIDOU_B3I_TELEMETRY_SYMBOLS_PER_BIT * BEIDOU_B3I_CODE_PERIOD_MS),
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d_TOW_at_Preamble_ms(0U),
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d_TOW_at_current_symbol_ms(0U),
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d_flag_SOW_set(false),
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d_flag_frame_sync(false),
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d_flag_preamble(false),
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d_flag_valid_word(false),
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d_sent_tlm_failed_msg(false),
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d_dump(conf.dump),
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d_dump_mat(conf.dump_mat),
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d_remove_dat(conf.remove_dat),
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d_enable_navdata_monitor(conf.enable_navdata_monitor),
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d_dump_crc_stats(conf.dump_crc_stats)
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{
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// prevent telemetry symbols accumulation in output buffers
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this->set_max_noutput_items(1);
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// Ephemeris data port out
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this->message_port_register_out(pmt::mp("telemetry"));
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// Control messages to tracking block
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this->message_port_register_out(pmt::mp("telemetry_to_trk"));
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if (d_enable_navdata_monitor)
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{
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// register nav message monitor out
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this->message_port_register_out(pmt::mp("Nav_msg_from_TLM"));
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d_nav_msg_packet.system = std::string("C");
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d_nav_msg_packet.signal = std::string("B3");
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}
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d_satellite = Gnss_Satellite(satellite.get_system(), satellite.get_PRN());
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LOG(INFO) << "Initializing BeiDou B3I Telemetry Decoding for satellite " << this->d_satellite;
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// Setting samples of preamble code
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for (int32_t i = 0; i < d_symbols_per_preamble; i++)
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{
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if (BEIDOU_DNAV_PREAMBLE[i] == '1')
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{
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d_preamble_samples[i] = 1;
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}
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else
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{
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d_preamble_samples[i] = -1;
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}
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}
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d_symbol_history.set_capacity(d_required_symbols);
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if (d_dump_crc_stats)
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{
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// initialize the telemetry CRC statistics class
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d_Tlm_CRC_Stats = std::make_unique<Tlm_CRC_Stats>();
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d_Tlm_CRC_Stats->initialize(conf.dump_crc_stats_filename);
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}
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else
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{
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d_Tlm_CRC_Stats = nullptr;
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}
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}
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beidou_b3i_telemetry_decoder_gs::~beidou_b3i_telemetry_decoder_gs()
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{
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DLOG(INFO) << "BeiDou B3I Telemetry decoder block (channel " << d_channel << ") destructor called.";
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size_t pos = 0;
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if (d_dump_file.is_open() == true)
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{
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pos = d_dump_file.tellp();
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try
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{
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d_dump_file.close();
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}
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catch (const std::exception &ex)
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{
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LOG(WARNING) << "Exception in destructor closing the dump file " << ex.what();
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}
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if (pos == 0)
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{
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if (!tlm_remove_file(d_dump_filename))
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{
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LOG(WARNING) << "Error deleting temporary file";
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}
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}
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}
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if (d_dump && (pos != 0) && d_dump_mat)
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{
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save_tlm_matfile(d_dump_filename);
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if (d_remove_dat)
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{
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if (!tlm_remove_file(d_dump_filename))
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{
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LOG(WARNING) << "Error deleting temporary file";
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}
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}
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}
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}
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void beidou_b3i_telemetry_decoder_gs::decode_bch15_11_01(const int32_t *bits,
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std::array<int32_t, 15> &decbits)
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{
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int32_t bit;
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int32_t err;
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std::array<int32_t, 4> reg{-1, -1, -1, -1};
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const std::array<int32_t, 15> errind{14, 13, 10, 12, 6, 9, 4, 11, 0, 5, 7, 8, 1, 3, 2};
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for (uint32_t i = 0; i < 15; i++)
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{
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decbits[i] = bits[i];
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}
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for (uint32_t i = 0; i < 15; i++)
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{
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bit = reg[3];
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reg[3] = reg[2];
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reg[2] = reg[1];
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reg[1] = reg[0];
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reg[0] = bits[i] * bit;
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reg[1] *= bit;
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}
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for (uint32_t i = 0; i < 4; ++i)
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{
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reg[i] = (reg[i] + 1) / 2;
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}
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err = reg[0] + reg[1] * 2 + reg[2] * 4 + reg[3] * 8;
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if (err > 0 && err < 16)
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{
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decbits[errind[err - 1]] *= -1;
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}
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}
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void beidou_b3i_telemetry_decoder_gs::decode_word(
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int32_t word_counter,
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const float *enc_word_symbols,
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int32_t *dec_word_symbols)
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{
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std::array<int32_t, 30> bitsbch{};
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std::array<int32_t, 15> first_branch{};
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std::array<int32_t, 15> second_branch{};
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if (word_counter == 1)
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{
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for (uint32_t j = 0; j < 30; j++)
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{
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dec_word_symbols[j] = static_cast<int32_t>(enc_word_symbols[j] > 0) ? (1) : (-1);
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}
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}
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else
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{
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for (uint32_t r = 0; r < 2; r++)
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{
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for (uint32_t c = 0; c < 15; c++)
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{
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bitsbch[r * 15 + c] = static_cast<int32_t>(enc_word_symbols[c * 2 + r] > 0) ? (1) : (-1);
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}
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}
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decode_bch15_11_01(&bitsbch[0], first_branch);
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decode_bch15_11_01(&bitsbch[15], second_branch);
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for (uint32_t j = 0; j < 11; j++)
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{
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dec_word_symbols[j] = first_branch[j];
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dec_word_symbols[j + 11] = second_branch[j];
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}
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for (uint32_t j = 0; j < 4; j++)
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{
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dec_word_symbols[j + 22] = first_branch[11 + j];
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dec_word_symbols[j + 26] = second_branch[11 + j];
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}
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}
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}
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void beidou_b3i_telemetry_decoder_gs::decode_subframe(float *frame_symbols, double cn0)
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{
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// 1. Transform from symbols to bits
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std::string data_bits;
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data_bits.reserve(BEIDOU_DNAV_WORDS_SUBFRAME * BEIDOU_DNAV_WORD_LENGTH_BITS);
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std::array<int32_t, 30> dec_word_bits{};
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// Decode each word in subframe
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for (uint32_t ii = 0; ii < BEIDOU_DNAV_WORDS_SUBFRAME; ii++)
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{
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// decode the word
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decode_word((ii + 1), &frame_symbols[ii * 30], dec_word_bits.data());
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// Save word to string format
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for (uint32_t jj = 0; jj < (BEIDOU_DNAV_WORD_LENGTH_BITS); jj++)
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{
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data_bits.push_back((dec_word_bits[jj] > 0) ? ('1') : ('0'));
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}
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}
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if (d_enable_navdata_monitor)
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{
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d_nav_msg_packet.nav_message = data_bits;
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}
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if (d_satellite.get_PRN() > 0 && d_satellite.get_PRN() < 6)
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{
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d_nav.d2_subframe_decoder(data_bits);
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}
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else
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{
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d_nav.d1_subframe_decoder(data_bits);
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}
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// 3. Check operation executed correctly
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bool crc_ok = d_nav.get_flag_CRC_test();
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if (crc_ok)
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{
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DLOG(INFO) << "BeiDou DNAV CRC correct in channel " << d_channel
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<< " from satellite " << d_satellite << " with CN0=" << cn0 << " dB-Hz";
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}
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else
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{
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DLOG(INFO) << "BeiDou DNAV CRC error in channel " << d_channel
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<< " from satellite " << d_satellite << " with CN0=" << cn0 << " dB-Hz";
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}
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if (d_dump_crc_stats)
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{
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// update CRC statistics
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d_Tlm_CRC_Stats->update_CRC_stats(crc_ok);
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}
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// 4. Push the new navigation data to the queues
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if (d_nav.have_new_ephemeris() == true)
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{
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// get object for this SV (mandatory)
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const std::shared_ptr<Beidou_Dnav_Ephemeris> tmp_obj =
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std::make_shared<Beidou_Dnav_Ephemeris>(d_nav.get_ephemeris());
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this->message_port_pub(pmt::mp("telemetry"), pmt::make_any(tmp_obj));
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LOG(INFO) << "BEIDOU DNAV Ephemeris have been received in channel"
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<< d_channel << " from satellite " << d_satellite << " with CN0=" << cn0 << " dB-Hz";
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#if __cplusplus == 201103L
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const int default_precision = std::cout.precision();
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#else
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const auto default_precision{std::cout.precision()};
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#endif
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std::cout << TEXT_YELLOW << "New BEIDOU B3I DNAV message received in channel " << d_channel
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<< ": ephemeris from satellite " << d_satellite
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<< " with CN0=" << std::setprecision(2) << cn0 << std::setprecision(default_precision)
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<< " dB-Hz" << TEXT_RESET << std::endl;
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}
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if (d_nav.have_new_utc_model() == true)
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{
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// get object for this SV (mandatory)
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const std::shared_ptr<Beidou_Dnav_Utc_Model> tmp_obj =
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std::make_shared<Beidou_Dnav_Utc_Model>(d_nav.get_utc_model());
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this->message_port_pub(pmt::mp("telemetry"), pmt::make_any(tmp_obj));
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LOG(INFO) << "BEIDOU DNAV UTC Model data have been received in channel"
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<< d_channel << " from satellite " << d_satellite;
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#if __cplusplus == 201103L
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const int default_precision = std::cout.precision();
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#else
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const auto default_precision{std::cout.precision()};
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#endif
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std::cout << TEXT_YELLOW << "New BEIDOU B3I DNAV utc model message received in channel "
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<< d_channel << ": UTC model parameters from satellite "
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<< d_satellite
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<< " with CN0=" << std::setprecision(2) << cn0 << std::setprecision(default_precision)
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<< " dB-Hz" << TEXT_RESET << std::endl;
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}
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if (d_nav.have_new_iono() == true)
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{
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// get object for this SV (mandatory)
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const std::shared_ptr<Beidou_Dnav_Iono> tmp_obj =
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std::make_shared<Beidou_Dnav_Iono>(d_nav.get_iono());
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this->message_port_pub(pmt::mp("telemetry"), pmt::make_any(tmp_obj));
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LOG(INFO) << "BEIDOU DNAV Iono data have been received in channel" << d_channel
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<< " from satellite " << d_satellite << " with CN0=" << cn0 << " dB-Hz";
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#if __cplusplus == 201103L
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const int default_precision = std::cout.precision();
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#else
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const auto default_precision{std::cout.precision()};
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#endif
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std::cout << TEXT_YELLOW << "New BEIDOU B3I DNAV Iono message received in channel "
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<< d_channel << ": Iono model parameters from satellite "
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<< d_satellite << " with CN0=" << std::setprecision(2) << cn0 << std::setprecision(default_precision)
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<< " dB-Hz" << TEXT_RESET << std::endl;
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}
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if (d_nav.have_new_almanac() == true)
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{
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// unsigned int slot_nbr = d_nav.i_alm_satellite_PRN;
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// std::shared_ptr<Beidou_Dnav_Almanac> tmp_obj =
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// std::make_shared<Beidou_Dnav_Almanac>(d_nav.get_almanac(slot_nbr));
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// this->message_port_pub(pmt::mp("telemetry"),
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// pmt::make_any(tmp_obj));
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LOG(INFO) << "BEIDOU DNAV Almanac data have been received in channel"
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<< d_channel << " from satellite " << d_satellite << " with CN0=" << cn0 << " dB-Hz";
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#if __cplusplus == 201103L
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const int default_precision = std::cout.precision();
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#else
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const auto default_precision{std::cout.precision()};
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#endif
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std::cout << TEXT_YELLOW << "New BEIDOU B3I DNAV almanac received in channel " << d_channel
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<< " from satellite " << d_satellite
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<< " with CN0=" << std::setprecision(2) << cn0 << std::setprecision(default_precision)
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<< " dB-Hz" << TEXT_RESET << std::endl;
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}
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}
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void beidou_b3i_telemetry_decoder_gs::set_satellite(
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const Gnss_Satellite &satellite)
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{
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uint32_t sat_prn = 0;
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d_satellite = Gnss_Satellite(satellite.get_system(), satellite.get_PRN());
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DLOG(INFO) << "Setting decoder Finite State Machine to satellite "
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<< d_satellite;
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DLOG(INFO) << "Navigation Satellite set to " << d_satellite;
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// Update satellite information for DNAV decoder
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sat_prn = d_satellite.get_PRN();
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d_nav.set_satellite_PRN(sat_prn);
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d_nav.set_signal_type(5); // BDS: data source (0:unknown,1:B1I,2:B1Q,3:B2I,4:B2Q,5:B3I,6:B3Q)
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// Update tel dec parameters for D2 NAV Messages
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if ((sat_prn > 0 && sat_prn < 6) || sat_prn > 58)
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{
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d_symbols_per_preamble = BEIDOU_DNAV_PREAMBLE_LENGTH_SYMBOLS;
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d_samples_per_preamble = BEIDOU_DNAV_PREAMBLE_LENGTH_SYMBOLS;
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d_preamble_period_samples = BEIDOU_DNAV_PREAMBLE_PERIOD_SYMBOLS;
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// Setting samples of preamble code
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for (int32_t i = 0; i < d_symbols_per_preamble; i++)
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{
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if (BEIDOU_DNAV_PREAMBLE[i] == '1')
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{
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d_preamble_samples[i] = 1;
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}
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else
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{
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d_preamble_samples[i] = -1;
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}
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}
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d_symbol_duration_ms = BEIDOU_B3I_GEO_TELEMETRY_SYMBOLS_PER_BIT * BEIDOU_B3I_CODE_PERIOD_MS;
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d_required_symbols = BEIDOU_DNAV_SUBFRAME_SYMBOLS + d_samples_per_preamble;
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d_symbol_history.set_capacity(d_required_symbols);
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}
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else
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{
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// back to normal satellites
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d_symbol_duration_ms = BEIDOU_B3I_TELEMETRY_SYMBOLS_PER_BIT * BEIDOU_B3I_CODE_PERIOD_MS;
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d_symbols_per_preamble = BEIDOU_DNAV_PREAMBLE_LENGTH_SYMBOLS;
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d_samples_per_preamble = BEIDOU_DNAV_PREAMBLE_LENGTH_SYMBOLS;
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d_preamble_period_samples = BEIDOU_DNAV_PREAMBLE_PERIOD_SYMBOLS;
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// Setting samples of preamble code
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for (int32_t i = 0; i < d_symbols_per_preamble; i++)
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{
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if (BEIDOU_DNAV_PREAMBLE[i] == '1')
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{
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d_preamble_samples[i] = 1;
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}
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else
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{
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d_preamble_samples[i] = -1;
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}
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}
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d_required_symbols = BEIDOU_DNAV_SUBFRAME_SYMBOLS + d_samples_per_preamble;
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d_symbol_history.set_capacity(d_required_symbols);
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}
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}
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void beidou_b3i_telemetry_decoder_gs::set_channel(int32_t channel)
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{
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d_channel = channel;
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LOG(INFO) << "Navigation channel set to " << channel;
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// ############# ENABLE DATA FILE LOG #################
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if (d_dump == true)
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{
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if (d_dump_file.is_open() == false)
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{
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try
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{
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d_dump_filename.append(std::to_string(d_channel));
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d_dump_filename.append(".dat");
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d_dump_file.exceptions(std::ofstream::failbit | std::ofstream::badbit);
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d_dump_file.open(d_dump_filename.c_str(),
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std::ios::out | std::ios::binary);
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LOG(INFO) << "Telemetry decoder dump enabled on channel " << d_channel
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<< " Log file: " << d_dump_filename.c_str();
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}
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catch (const std::ofstream::failure &e)
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{
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LOG(WARNING) << "channel " << d_channel
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<< ": exception opening Beidou TLM dump file. "
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<< e.what();
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}
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}
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}
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if (d_dump_crc_stats)
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{
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// set the channel number for the telemetry CRC statistics
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// disable the telemetry CRC statistics if there is a problem opening the output file
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d_dump_crc_stats = d_Tlm_CRC_Stats->set_channel(d_channel);
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}
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}
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void beidou_b3i_telemetry_decoder_gs::reset()
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{
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d_last_valid_preamble = d_sample_counter;
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d_TOW_at_current_symbol_ms = 0;
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d_sent_tlm_failed_msg = false;
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d_flag_valid_word = false;
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DLOG(INFO) << "Beidou B3I Telemetry decoder reset for satellite " << d_satellite;
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}
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int beidou_b3i_telemetry_decoder_gs::general_work(
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int noutput_items __attribute__((unused)),
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gr_vector_int &ninput_items __attribute__((unused)),
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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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int32_t corr_value = 0;
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int32_t preamble_diff = 0;
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auto **out = reinterpret_cast<Gnss_Synchro **>(&output_items[0]); // Get the output buffer pointer
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const auto **in = reinterpret_cast<const Gnss_Synchro **>(&input_items[0]); // Get the input buffer pointer
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Gnss_Synchro current_symbol{}; // structure to save the synchronization
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// information and send the output object to the
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// next block
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// 1. Copy the current tracking output
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current_symbol = in[0][0];
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d_symbol_history.push_back(current_symbol.Prompt_I); // add new symbol to the symbol queue
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d_sample_counter++; // count for the processed samples
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consume_each(1);
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d_flag_preamble = false;
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if (d_symbol_history.size() >= d_required_symbols)
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{
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// ******* preamble correlation ********
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for (int32_t i = 0; i < d_samples_per_preamble; i++)
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{
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if (d_symbol_history[i] < 0) // symbols clipping
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{
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corr_value -= d_preamble_samples[i];
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}
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else
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{
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corr_value += d_preamble_samples[i];
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}
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}
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}
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// ******* frame sync ******************
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if (d_stat == 0) // no preamble information
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{
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if (abs(corr_value) >= d_samples_per_preamble)
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{
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// Record the preamble sample stamp
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d_preamble_index = d_sample_counter;
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DLOG(INFO) << "Preamble detection for BEIDOU B3I SAT " << this->d_satellite;
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// Enter into frame pre-detection status
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d_stat = 1;
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}
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}
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else if (d_stat == 1) // possible preamble lock
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{
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if (abs(corr_value) >= d_samples_per_preamble)
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{
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// check preamble separation
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preamble_diff = static_cast<int32_t>(d_sample_counter - d_preamble_index);
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if (abs(preamble_diff - d_preamble_period_samples) == 0)
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{
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// try to decode frame
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DLOG(INFO) << "Starting BeiDou DNAV frame decoding for BeiDou B3I SAT "
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<< this->d_satellite;
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d_preamble_index = d_sample_counter; // record the preamble sample stamp
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d_stat = 2;
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// ******* SAMPLES TO SYMBOLS *******
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if (corr_value > 0) // normal PLL lock
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{
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for (uint32_t i = 0; i < BEIDOU_DNAV_PREAMBLE_PERIOD_SYMBOLS; i++)
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{
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d_subframe_symbols[i] = d_symbol_history[i];
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}
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}
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else // 180 deg. inverted carrier phase PLL lock
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{
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for (uint32_t i = 0; i < BEIDOU_DNAV_PREAMBLE_PERIOD_SYMBOLS; i++)
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{
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d_subframe_symbols[i] = -d_symbol_history[i];
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}
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}
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// call the decoder
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decode_subframe(d_subframe_symbols.data(), current_symbol.CN0_dB_hz);
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if (d_nav.get_flag_CRC_test() == true)
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{
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d_CRC_error_counter = 0;
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d_flag_preamble = true; // valid preamble indicator (initialized to false every work())
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d_preamble_index = d_sample_counter; // record the preamble sample stamp (t_P)
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if (!d_flag_frame_sync)
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{
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d_flag_frame_sync = true;
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DLOG(INFO) << "BeiDou DNAV frame sync found for SAT "
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<< this->d_satellite;
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}
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}
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else
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{
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d_CRC_error_counter++;
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d_preamble_index = d_sample_counter; // record the preamble sample stamp
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if (d_CRC_error_counter > CRC_ERROR_LIMIT)
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{
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DLOG(INFO) << "BeiDou DNAV frame sync lost for SAT "
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<< this->d_satellite;
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d_flag_frame_sync = false;
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d_stat = 0;
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d_flag_SOW_set = false;
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}
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}
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}
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else
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{
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if (preamble_diff > d_preamble_period_samples)
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{
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d_stat = 0; // start again
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}
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DLOG(INFO) << "Failed BeiDou DNAV frame decoding for BeiDou B3I SAT "
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<< this->d_satellite;
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}
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}
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}
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else if (d_stat == 2) // preamble acquired
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{
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if (d_sample_counter == d_preamble_index + static_cast<uint64_t>(d_preamble_period_samples))
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{
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// ******* SAMPLES TO SYMBOLS *******
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if (corr_value > 0) // normal PLL lock
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{
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for (uint32_t i = 0; i < BEIDOU_DNAV_PREAMBLE_PERIOD_SYMBOLS; i++)
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{
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d_subframe_symbols[i] = d_symbol_history[i];
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}
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}
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else // 180 deg. inverted carrier phase PLL lock
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{
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for (uint32_t i = 0; i < BEIDOU_DNAV_PREAMBLE_PERIOD_SYMBOLS; i++)
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{
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d_subframe_symbols[i] = -d_symbol_history[i];
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}
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}
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// call the decoder
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decode_subframe(d_subframe_symbols.data(), current_symbol.CN0_dB_hz);
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if (d_nav.get_flag_CRC_test() == true)
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{
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d_CRC_error_counter = 0;
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d_flag_preamble = true; // valid preamble indicator (initialized to false every work())
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d_preamble_index = d_sample_counter; // record the preamble sample stamp (t_P)
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if (!d_flag_frame_sync)
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{
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d_flag_frame_sync = true;
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DLOG(INFO) << "BeiDou DNAV frame sync found for SAT "
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<< this->d_satellite;
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}
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}
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else
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{
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d_CRC_error_counter++;
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d_preamble_index = d_sample_counter; // record the preamble sample stamp
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if (d_CRC_error_counter > CRC_ERROR_LIMIT)
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{
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DLOG(INFO) << "BeiDou DNAV frame sync lost for SAT "
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<< this->d_satellite;
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d_flag_frame_sync = false;
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d_stat = 0;
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d_flag_SOW_set = false;
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}
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}
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}
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}
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// UPDATE GNSS SYNCHRO DATA
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// 2. Add the telemetry decoder information
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if (this->d_flag_preamble == true && d_nav.get_flag_new_SOW_available() == true)
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// update TOW at the preamble instant
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{
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// Reporting sow as gps time of week
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d_TOW_at_Preamble_ms = static_cast<uint32_t>((d_nav.get_SOW() + BEIDOU_DNAV_BDT2GPST_LEAP_SEC_OFFSET) * 1000.0);
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// check TOW update consistency
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const uint32_t last_d_TOW_at_current_symbol_ms = d_TOW_at_current_symbol_ms;
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// compute new TOW
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d_TOW_at_current_symbol_ms = d_TOW_at_Preamble_ms + d_required_symbols * d_symbol_duration_ms;
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d_flag_SOW_set = true;
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d_nav.set_flag_new_SOW_available(false);
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if (last_d_TOW_at_current_symbol_ms != 0 && abs(static_cast<int64_t>(d_TOW_at_current_symbol_ms) - int64_t(last_d_TOW_at_current_symbol_ms)) > static_cast<int64_t>(d_symbol_duration_ms))
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{
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LOG(INFO) << "Warning: BEIDOU B3I TOW update in ch " << d_channel
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<< " does not match the TLM TOW counter " << static_cast<int64_t>(d_TOW_at_current_symbol_ms) - int64_t(last_d_TOW_at_current_symbol_ms) << " ms \n";
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d_TOW_at_current_symbol_ms = 0;
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d_flag_valid_word = false;
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}
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else
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{
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d_last_valid_preamble = d_sample_counter;
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d_flag_valid_word = true;
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}
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if (d_enable_navdata_monitor && !d_nav_msg_packet.nav_message.empty())
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{
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d_nav_msg_packet.prn = static_cast<int32_t>(current_symbol.PRN);
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d_nav_msg_packet.tow_at_current_symbol_ms = static_cast<int32_t>(d_TOW_at_current_symbol_ms);
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const std::shared_ptr<Nav_Message_Packet> tmp_obj = std::make_shared<Nav_Message_Packet>(d_nav_msg_packet);
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this->message_port_pub(pmt::mp("Nav_msg_from_TLM"), pmt::make_any(tmp_obj));
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d_nav_msg_packet.nav_message = "";
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}
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}
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else
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{
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if (d_flag_valid_word)
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{
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d_TOW_at_current_symbol_ms += d_symbol_duration_ms;
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if (current_symbol.Flag_valid_symbol_output == false)
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{
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d_flag_valid_word = false;
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}
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}
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}
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if (d_flag_valid_word == true)
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{
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current_symbol.TOW_at_current_symbol_ms = d_TOW_at_current_symbol_ms;
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current_symbol.Flag_valid_word = d_flag_valid_word;
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if (d_dump == true)
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{
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// MULTIPLEXED FILE RECORDING - Record results to file
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try
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{
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double tmp_double;
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uint64_t tmp_ulong_int;
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int32_t tmp_int;
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tmp_double = static_cast<double>(d_TOW_at_current_symbol_ms) / 1000.0;
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d_dump_file.write(reinterpret_cast<char *>(&tmp_double), sizeof(double));
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tmp_ulong_int = current_symbol.Tracking_sample_counter;
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d_dump_file.write(reinterpret_cast<char *>(&tmp_ulong_int), sizeof(uint64_t));
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tmp_double = static_cast<double>(d_TOW_at_Preamble_ms) / 1000.0;
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d_dump_file.write(reinterpret_cast<char *>(&tmp_double), sizeof(double));
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tmp_int = (current_symbol.Prompt_I > 0.0 ? 1 : -1);
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d_dump_file.write(reinterpret_cast<char *>(&tmp_int), sizeof(int32_t));
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tmp_int = static_cast<int32_t>(current_symbol.PRN);
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d_dump_file.write(reinterpret_cast<char *>(&tmp_int), sizeof(int32_t));
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}
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catch (const std::ofstream::failure &e)
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{
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LOG(WARNING) << "Exception writing Telemetry GPS L5 dump file " << e.what();
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}
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}
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// 3. Make the output (copy the object contents to the GNURadio reserved memory)
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*out[0] = current_symbol;
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return 1;
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}
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return 0;
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}
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