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gnss-sdr/src/algorithms/telemetry_decoder/gnuradio_blocks/gps_l2c_telemetry_decoder_cc.cc

238 lines
9.9 KiB
C++

/*!
* \file gps_l2c_telemetry_decoder_cc.cc
* \brief Implementation of a NAV message demodulator block based on
* Kay Borre book MATLAB-based GPS receiver
* \author Javier Arribas, 2015. jarribas(at)cttc.es
*
* -------------------------------------------------------------------------
*
* Copyright (C) 2010-2015 (see AUTHORS file for a list of contributors)
*
* GNSS-SDR is a software defined Global Navigation
* Satellite Systems receiver
*
* This file is part of GNSS-SDR.
*
* GNSS-SDR is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* GNSS-SDR is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GNSS-SDR. If not, see <http://www.gnu.org/licenses/>.
*
* -------------------------------------------------------------------------
*/
#include <bitset>
#include <iostream>
#include <sstream>
#include <gnuradio/io_signature.h>
#include <glog/logging.h>
#include <boost/lexical_cast.hpp>
#include "gnss_synchro.h"
#include "gps_l2c_telemetry_decoder_cc.h"
using google::LogMessage;
gps_l2c_telemetry_decoder_cc_sptr
gps_l2c_make_telemetry_decoder_cc(const Gnss_Satellite & satellite, bool dump)
{
return gps_l2c_telemetry_decoder_cc_sptr(new gps_l2c_telemetry_decoder_cc(satellite, dump));
}
gps_l2c_telemetry_decoder_cc::gps_l2c_telemetry_decoder_cc(
const Gnss_Satellite & satellite, bool dump) : gr::block("gps_l2c_telemetry_decoder_cc",
gr::io_signature::make(1, 1, sizeof(Gnss_Synchro)),
gr::io_signature::make(1, 1, sizeof(Gnss_Synchro)))
{
// Telemetry Bit transition synchronization port out
this->message_port_register_out(pmt::mp("preamble_timestamp_s"));
// Ephemeris data port out
this->message_port_register_out(pmt::mp("telemetry"));
// initialize internal vars
d_dump = dump;
d_satellite = Gnss_Satellite(satellite.get_system(), satellite.get_PRN());
DLOG(INFO) << "GPS L2C M TELEMETRY PROCESSING: satellite " << d_satellite;
//set_output_multiple (1);
d_channel = 0;
d_flag_valid_word = false;
d_TOW_at_current_symbol = 0;
d_TOW_at_Preamble = 0;
d_state = 0; //initial state
d_crc_error_count = 0;
//initialize the CNAV frame decoder (libswiftcnav)
cnav_msg_decoder_init(&d_cnav_decoder);
}
gps_l2c_telemetry_decoder_cc::~gps_l2c_telemetry_decoder_cc()
{
if(d_dump_file.is_open() == true)
{
try
{
d_dump_file.close();
}
catch(const std::exception & ex)
{
LOG(WARNING) << "Exception in destructor closing the dump file " << ex.what();
}
}
}
int gps_l2c_telemetry_decoder_cc::general_work (int noutput_items __attribute__((unused)), gr_vector_int &ninput_items __attribute__((unused)),
gr_vector_const_void_star &input_items, gr_vector_void_star &output_items)
{
// get pointers on in- and output gnss-synchro objects
Gnss_Synchro *out = reinterpret_cast<Gnss_Synchro *>(output_items[0]); // Get the output buffer pointer
const Gnss_Synchro *in = reinterpret_cast<const Gnss_Synchro *>(input_items[0]); // Get the input buffer pointer
bool flag_new_cnav_frame = false;
cnav_msg_t msg;
u32 delay = 0;
//add the symbol to the decoder
u8 symbol_clip = static_cast<u8>(in[0].Prompt_I > 0) * 255;
flag_new_cnav_frame = cnav_msg_decoder_add_symbol(&d_cnav_decoder, symbol_clip, &msg, &delay);
consume_each(1); //one by one
// UPDATE GNSS SYNCHRO DATA
Gnss_Synchro current_synchro_data; //structure to save the synchronization information and send the output object to the next block
//1. Copy the current tracking output
current_synchro_data = in[0];
//2. Add the telemetry decoder information
//check if new CNAV frame is available
if (flag_new_cnav_frame == true)
{
std::bitset<GPS_L2_CNAV_DATA_PAGE_BITS> raw_bits;
//Expand packet bits to bitsets. Notice the reverse order of the bits sequence, required by the CNAV message decoder
for (u32 i = 0; i < GPS_L2_CNAV_DATA_PAGE_BITS ; i++)
{
raw_bits[GPS_L2_CNAV_DATA_PAGE_BITS - 1 - i] = ((msg.raw_msg[i/8] >> (7 - i%8)) & 1u);
}
d_CNAV_Message.decode_page(raw_bits);
//Push the new navigation data to the queues
if (d_CNAV_Message.have_new_ephemeris() == true)
{
// get ephemeris object for this SV
std::shared_ptr<Gps_CNAV_Ephemeris> tmp_obj = std::make_shared<Gps_CNAV_Ephemeris>(d_CNAV_Message.get_ephemeris());
std::cout << "New GPS CNAV message received: ephemeris from satellite " << d_satellite << std::endl;
this->message_port_pub(pmt::mp("telemetry"), pmt::make_any(tmp_obj));
}
if (d_CNAV_Message.have_new_iono() == true)
{
std::shared_ptr<Gps_CNAV_Iono> tmp_obj = std::make_shared<Gps_CNAV_Iono>(d_CNAV_Message.get_iono());
std::cout << "New GPS CNAV message received: iono model parameters from satellite " << d_satellite << std::endl;
this->message_port_pub(pmt::mp("telemetry"), pmt::make_any(tmp_obj));
}
if (d_CNAV_Message.have_new_utc_model() == true)
{
std::shared_ptr<Gps_CNAV_Utc_Model> tmp_obj = std::make_shared<Gps_CNAV_Utc_Model>(d_CNAV_Message.get_utc_model());
std::cout << "New GPS CNAV message received: UTC model parameters from satellite " << d_satellite << std::endl;
this->message_port_pub(pmt::mp("telemetry"), pmt::make_any(tmp_obj));
}
//update TOW at the preamble instant
d_TOW_at_Preamble = static_cast<int>(msg.tow);
//std::cout<<"["<<(int)msg.prn<<"] deco delay: "<<delay<<"[symbols]"<<std::endl;
//* The time of the last input symbol can be computed from the message ToW and
//* delay by the formulae:
//* \code
//* symbolTime_ms = msg->tow * 6000 + *pdelay * 20
d_TOW_at_current_symbol = static_cast<double>(msg.tow) * 6.0 + static_cast<double>(delay) * GPS_L2_M_PERIOD + 12 * GPS_L2_M_PERIOD;
d_TOW_at_current_symbol = floor(d_TOW_at_current_symbol * 1000.0) / 1000.0;
d_flag_valid_word = true;
}
else
{
d_TOW_at_current_symbol += GPS_L2_M_PERIOD;
if (current_synchro_data.Flag_valid_symbol_output == false)
{
d_flag_valid_word = false;
}
}
current_synchro_data.TOW_at_current_symbol_s = d_TOW_at_current_symbol;
current_synchro_data.Flag_valid_word = d_flag_valid_word;
// if (flag_PLL_180_deg_phase_locked == true)
// {
// //correct the accumulated phase for the Costas loop phase shift, if required
// current_synchro_data.Carrier_phase_rads += GPS_PI;
// }
if(d_dump == true)
{
// MULTIPLEXED FILE RECORDING - Record results to file
try
{
double tmp_double;
unsigned long int tmp_ulong_int;
tmp_double = d_TOW_at_current_symbol;
d_dump_file.write(reinterpret_cast<char*>(&tmp_double), sizeof(double));
tmp_ulong_int = current_synchro_data.Tracking_sample_counter;
d_dump_file.write(reinterpret_cast<char*>(&tmp_ulong_int), sizeof(unsigned long int));
tmp_double = d_TOW_at_Preamble;
d_dump_file.write(reinterpret_cast<char*>(&tmp_double), sizeof(double));
}
catch (const std::ifstream::failure & e)
{
LOG(WARNING) << "Exception writing observables dump file " << e.what();
}
}
//3. Make the output (copy the object contents to the GNURadio reserved memory)
out[0] = current_synchro_data;
return 1;
}
void gps_l2c_telemetry_decoder_cc::set_satellite(const Gnss_Satellite & satellite)
{
d_satellite = Gnss_Satellite(satellite.get_system(), satellite.get_PRN());
LOG(INFO) << "GPS L2C CNAV telemetry decoder in channel " << this->d_channel << " set to satellite " << d_satellite;
}
void gps_l2c_telemetry_decoder_cc::set_channel(int channel)
{
d_channel = channel;
LOG(INFO) << "GPS L2C CNAV channel set to " << channel;
// ############# ENABLE DATA FILE LOG #################
if (d_dump == true)
{
if (d_dump_file.is_open() == false)
{
try
{
d_dump_filename = "telemetry_L2CM_";
d_dump_filename.append(boost::lexical_cast<std::string>(d_channel));
d_dump_filename.append(".dat");
d_dump_file.exceptions ( std::ifstream::failbit | std::ifstream::badbit );
d_dump_file.open(d_dump_filename.c_str(), std::ios::out | std::ios::binary);
LOG(INFO) << "Telemetry decoder dump enabled on channel " << d_channel
<< " Log file: " << d_dump_filename.c_str();
}
catch (const std::ifstream::failure &e)
{
LOG(WARNING) << "channel " << d_channel << " Exception opening trk dump file " << e.what();
}
}
}
}