mirror of https://github.com/gnss-sdr/gnss-sdr
407 lines
24 KiB
C++
407 lines
24 KiB
C++
/*!
|
|
* \file galileo_e1_ls_pvt.cc
|
|
* \brief Implementation of a Least Squares Position, Velocity, and Time
|
|
* (PVT) solver, based on K.Borre's Matlab receiver.
|
|
* \author Javier Arribas, 2011. jarribas(at)cttc.es
|
|
*
|
|
* -------------------------------------------------------------------------
|
|
*
|
|
* Copyright (C) 2010-2018 (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 <https://www.gnu.org/licenses/>.
|
|
*
|
|
* -------------------------------------------------------------------------
|
|
*/
|
|
|
|
#include "hybrid_ls_pvt.h"
|
|
#include "Galileo_E1.h"
|
|
#include "GPS_L1_CA.h"
|
|
#include "GPS_L2C.h"
|
|
#include <glog/logging.h>
|
|
|
|
|
|
using google::LogMessage;
|
|
|
|
hybrid_ls_pvt::hybrid_ls_pvt(int nchannels, std::string dump_filename, bool flag_dump_to_file) : Ls_Pvt()
|
|
{
|
|
// init empty ephemeris for all the available GNSS channels
|
|
d_nchannels = nchannels;
|
|
d_dump_filename = dump_filename;
|
|
d_flag_dump_enabled = flag_dump_to_file;
|
|
d_galileo_current_time = 0;
|
|
count_valid_position = 0;
|
|
this->set_averaging_flag(false);
|
|
// ############# ENABLE DATA FILE LOG #################
|
|
if (d_flag_dump_enabled == true)
|
|
{
|
|
if (d_dump_file.is_open() == false)
|
|
{
|
|
try
|
|
{
|
|
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) << "PVT lib dump enabled Log file: " << d_dump_filename.c_str();
|
|
}
|
|
catch (const std::ifstream::failure& e)
|
|
{
|
|
LOG(WARNING) << "Exception opening PVT lib dump file " << e.what();
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
hybrid_ls_pvt::~hybrid_ls_pvt()
|
|
{
|
|
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();
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
bool hybrid_ls_pvt::get_PVT(std::map<int, Gnss_Synchro> gnss_observables_map, double hybrid_current_time, bool flag_averaging)
|
|
{
|
|
std::map<int, Gnss_Synchro>::iterator gnss_observables_iter;
|
|
std::map<int, Galileo_Ephemeris>::iterator galileo_ephemeris_iter;
|
|
std::map<int, Gps_Ephemeris>::iterator gps_ephemeris_iter;
|
|
std::map<int, Gps_CNAV_Ephemeris>::iterator gps_cnav_ephemeris_iter;
|
|
|
|
arma::vec W; // channels weight vector
|
|
arma::vec obs; // pseudoranges observation vector
|
|
arma::mat satpos; // satellite positions matrix
|
|
|
|
int Galileo_week_number = 0;
|
|
int GPS_week = 0;
|
|
double utc = 0.0;
|
|
double GST = 0.0;
|
|
double secondsperweek = 604800.0;
|
|
|
|
//double utc_tx_corrected = 0.0; //utc computed at tx_time_corrected, added for Galileo constellation (in GPS utc is directly computed at TX_time_corrected_s)
|
|
double TX_time_corrected_s = 0.0;
|
|
double SV_clock_bias_s = 0.0;
|
|
|
|
this->set_averaging_flag(flag_averaging);
|
|
|
|
// ********************************************************************************
|
|
// ****** PREPARE THE LEAST SQUARES DATA (SV POSITIONS MATRIX AND OBS VECTORS) ****
|
|
// ********************************************************************************
|
|
int valid_obs = 0; //valid observations counter
|
|
|
|
for (gnss_observables_iter = gnss_observables_map.begin();
|
|
gnss_observables_iter != gnss_observables_map.end();
|
|
gnss_observables_iter++)
|
|
{
|
|
switch (gnss_observables_iter->second.System)
|
|
{
|
|
case 'E':
|
|
{
|
|
// 1 Gal - find the ephemeris for the current GALILEO SV observation. The SV PRN ID is the map key
|
|
galileo_ephemeris_iter = galileo_ephemeris_map.find(gnss_observables_iter->second.PRN);
|
|
if (galileo_ephemeris_iter != galileo_ephemeris_map.end())
|
|
{
|
|
/*!
|
|
* \todo Place here the satellite CN0 (power level, or weight factor)
|
|
*/
|
|
W.resize(valid_obs + 1, 1);
|
|
W(valid_obs) = 1;
|
|
|
|
// COMMON RX TIME PVT ALGORITHM
|
|
double Rx_time = hybrid_current_time;
|
|
double Tx_time = Rx_time - gnss_observables_iter->second.Pseudorange_m / GALILEO_C_m_s;
|
|
|
|
// 2- compute the clock drift using the clock model (broadcast) for this SV
|
|
SV_clock_bias_s = galileo_ephemeris_iter->second.sv_clock_drift(Tx_time);
|
|
|
|
// 3- compute the current ECEF position for this SV using corrected TX time
|
|
TX_time_corrected_s = Tx_time - SV_clock_bias_s;
|
|
galileo_ephemeris_iter->second.satellitePosition(TX_time_corrected_s);
|
|
|
|
//store satellite positions in a matrix
|
|
satpos.resize(3, valid_obs + 1);
|
|
satpos(0, valid_obs) = galileo_ephemeris_iter->second.d_satpos_X;
|
|
satpos(1, valid_obs) = galileo_ephemeris_iter->second.d_satpos_Y;
|
|
satpos(2, valid_obs) = galileo_ephemeris_iter->second.d_satpos_Z;
|
|
|
|
// 4- fill the observations vector with the corrected observables
|
|
obs.resize(valid_obs + 1, 1);
|
|
obs(valid_obs) = gnss_observables_iter->second.Pseudorange_m + SV_clock_bias_s * GALILEO_C_m_s - this->get_time_offset_s() * GALILEO_C_m_s;
|
|
this->set_visible_satellites_ID(valid_obs, galileo_ephemeris_iter->second.i_satellite_PRN);
|
|
this->set_visible_satellites_CN0_dB(valid_obs, gnss_observables_iter->second.CN0_dB_hz);
|
|
|
|
Galileo_week_number = galileo_ephemeris_iter->second.WN_5; //for GST
|
|
GST = galileo_ephemeris_iter->second.Galileo_System_Time(Galileo_week_number, hybrid_current_time);
|
|
|
|
// SV ECEF DEBUG OUTPUT
|
|
DLOG(INFO) << "ECEF satellite SV ID=" << galileo_ephemeris_iter->second.i_satellite_PRN
|
|
<< " X=" << galileo_ephemeris_iter->second.d_satpos_X
|
|
<< " [m] Y=" << galileo_ephemeris_iter->second.d_satpos_Y
|
|
<< " [m] Z=" << galileo_ephemeris_iter->second.d_satpos_Z
|
|
<< " [m] PR_obs=" << obs(valid_obs) << " [m]";
|
|
|
|
valid_obs++;
|
|
}
|
|
else // the ephemeris are not available for this SV
|
|
{
|
|
DLOG(INFO) << "No ephemeris data for SV " << gnss_observables_iter->second.PRN;
|
|
}
|
|
break;
|
|
}
|
|
case 'G':
|
|
{
|
|
// 1 GPS - find the ephemeris for the current GPS SV observation. The SV PRN ID is the map key
|
|
std::string sig_(gnss_observables_iter->second.Signal);
|
|
if (sig_.compare("1C") == 0)
|
|
{
|
|
gps_ephemeris_iter = gps_ephemeris_map.find(gnss_observables_iter->second.PRN);
|
|
if (gps_ephemeris_iter != gps_ephemeris_map.end())
|
|
{
|
|
/*!
|
|
* \todo Place here the satellite CN0 (power level, or weight factor)
|
|
*/
|
|
W.resize(valid_obs + 1, 1);
|
|
W(valid_obs) = 1;
|
|
|
|
// COMMON RX TIME PVT ALGORITHM MODIFICATION (Like RINEX files)
|
|
// first estimate of transmit time
|
|
double Rx_time = hybrid_current_time;
|
|
double Tx_time = Rx_time - gnss_observables_iter->second.Pseudorange_m / GPS_C_m_s;
|
|
|
|
// 2- compute the clock drift using the clock model (broadcast) for this SV, not including relativistic effect
|
|
SV_clock_bias_s = gps_ephemeris_iter->second.sv_clock_drift(Tx_time); //- gps_ephemeris_iter->second.d_TGD;
|
|
|
|
// 3- compute the current ECEF position for this SV using corrected TX time and obtain clock bias including relativistic effect
|
|
TX_time_corrected_s = Tx_time - SV_clock_bias_s;
|
|
double dtr = gps_ephemeris_iter->second.satellitePosition(TX_time_corrected_s);
|
|
|
|
//store satellite positions in a matrix
|
|
satpos.resize(3, valid_obs + 1);
|
|
satpos(0, valid_obs) = gps_ephemeris_iter->second.d_satpos_X;
|
|
satpos(1, valid_obs) = gps_ephemeris_iter->second.d_satpos_Y;
|
|
satpos(2, valid_obs) = gps_ephemeris_iter->second.d_satpos_Z;
|
|
|
|
// 4- fill the observations vector with the corrected pseudoranges
|
|
// compute code bias: TGD for single frequency
|
|
// See IS-GPS-200E section 20.3.3.3.3.2
|
|
double sqrt_Gamma = GPS_L1_FREQ_HZ / GPS_L2_FREQ_HZ;
|
|
double Gamma = sqrt_Gamma * sqrt_Gamma;
|
|
double P1_P2 = (1.0 - Gamma) * (gps_ephemeris_iter->second.d_TGD * GPS_C_m_s);
|
|
double Code_bias_m = P1_P2 / (1.0 - Gamma);
|
|
obs.resize(valid_obs + 1, 1);
|
|
obs(valid_obs) = gnss_observables_iter->second.Pseudorange_m + dtr * GPS_C_m_s - Code_bias_m - this->get_time_offset_s() * GPS_C_m_s;
|
|
this->set_visible_satellites_ID(valid_obs, gps_ephemeris_iter->second.i_satellite_PRN);
|
|
this->set_visible_satellites_CN0_dB(valid_obs, gnss_observables_iter->second.CN0_dB_hz);
|
|
|
|
// SV ECEF DEBUG OUTPUT
|
|
LOG(INFO) << "(new)ECEF GPS L1 CA satellite SV ID=" << gps_ephemeris_iter->second.i_satellite_PRN
|
|
<< " TX Time corrected=" << TX_time_corrected_s << " X=" << gps_ephemeris_iter->second.d_satpos_X
|
|
<< " [m] Y=" << gps_ephemeris_iter->second.d_satpos_Y
|
|
<< " [m] Z=" << gps_ephemeris_iter->second.d_satpos_Z
|
|
<< " [m] PR_obs=" << obs(valid_obs) << " [m]";
|
|
|
|
valid_obs++;
|
|
// compute the UTC time for this SV (just to print the associated UTC timestamp)
|
|
GPS_week = gps_ephemeris_iter->second.i_GPS_week;
|
|
}
|
|
else // the ephemeris are not available for this SV
|
|
{
|
|
DLOG(INFO) << "No ephemeris data for SV " << gnss_observables_iter->first;
|
|
}
|
|
}
|
|
if (sig_.compare("2S") == 0)
|
|
{
|
|
gps_cnav_ephemeris_iter = gps_cnav_ephemeris_map.find(gnss_observables_iter->second.PRN);
|
|
if (gps_cnav_ephemeris_iter != gps_cnav_ephemeris_map.end())
|
|
{
|
|
/*!
|
|
* \todo Place here the satellite CN0 (power level, or weight factor)
|
|
*/
|
|
W.resize(valid_obs + 1, 1);
|
|
W(valid_obs) = 1;
|
|
|
|
// COMMON RX TIME PVT ALGORITHM MODIFICATION (Like RINEX files)
|
|
// first estimate of transmit time
|
|
double Rx_time = hybrid_current_time;
|
|
double Tx_time = Rx_time - gnss_observables_iter->second.Pseudorange_m / GPS_C_m_s;
|
|
|
|
// 2- compute the clock drift using the clock model (broadcast) for this SV
|
|
SV_clock_bias_s = gps_cnav_ephemeris_iter->second.sv_clock_drift(Tx_time);
|
|
|
|
// 3- compute the current ECEF position for this SV using corrected TX time
|
|
TX_time_corrected_s = Tx_time - SV_clock_bias_s;
|
|
//std::cout<<"TX time["<<gps_cnav_ephemeris_iter->second.i_satellite_PRN<<"]="<<TX_time_corrected_s<<std::endl;
|
|
double dtr = gps_cnav_ephemeris_iter->second.satellitePosition(TX_time_corrected_s);
|
|
|
|
//store satellite positions in a matrix
|
|
satpos.resize(3, valid_obs + 1);
|
|
satpos(0, valid_obs) = gps_cnav_ephemeris_iter->second.d_satpos_X;
|
|
satpos(1, valid_obs) = gps_cnav_ephemeris_iter->second.d_satpos_Y;
|
|
satpos(2, valid_obs) = gps_cnav_ephemeris_iter->second.d_satpos_Z;
|
|
|
|
// 4- fill the observations vector with the corrected observables
|
|
obs.resize(valid_obs + 1, 1);
|
|
obs(valid_obs) = gnss_observables_iter->second.Pseudorange_m + dtr * GPS_C_m_s + SV_clock_bias_s * GPS_C_m_s;
|
|
this->set_visible_satellites_ID(valid_obs, gps_cnav_ephemeris_iter->second.i_satellite_PRN);
|
|
this->set_visible_satellites_CN0_dB(valid_obs, gnss_observables_iter->second.CN0_dB_hz);
|
|
|
|
GPS_week = gps_cnav_ephemeris_iter->second.i_GPS_week;
|
|
GPS_week = GPS_week % 1024; //Necessary due to the increase of WN bits in CNAV message (10 in GPS NAV and 13 in CNAV)
|
|
|
|
// SV ECEF DEBUG OUTPUT
|
|
LOG(INFO) << "(new)ECEF GPS L2M satellite SV ID=" << gps_cnav_ephemeris_iter->second.i_satellite_PRN
|
|
<< " TX Time corrected=" << TX_time_corrected_s
|
|
<< " X=" << gps_cnav_ephemeris_iter->second.d_satpos_X
|
|
<< " [m] Y=" << gps_cnav_ephemeris_iter->second.d_satpos_Y
|
|
<< " [m] Z=" << gps_cnav_ephemeris_iter->second.d_satpos_Z
|
|
<< " [m] PR_obs=" << obs(valid_obs) << " [m]";
|
|
|
|
valid_obs++;
|
|
}
|
|
else // the ephemeris are not available for this SV
|
|
{
|
|
DLOG(INFO) << "No ephemeris data for SV " << gnss_observables_iter->second.PRN;
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
default:
|
|
DLOG(INFO) << "Hybrid observables: Unknown GNSS";
|
|
break;
|
|
}
|
|
}
|
|
|
|
// ********************************************************************************
|
|
// ****** SOLVE LEAST SQUARES******************************************************
|
|
// ********************************************************************************
|
|
this->set_num_valid_observations(valid_obs);
|
|
|
|
LOG(INFO) << "HYBRID PVT: valid observations=" << valid_obs;
|
|
|
|
if (valid_obs >= 4)
|
|
{
|
|
arma::vec rx_position_and_time;
|
|
DLOG(INFO) << "satpos=" << satpos;
|
|
DLOG(INFO) << "obs=" << obs;
|
|
DLOG(INFO) << "W=" << W;
|
|
try
|
|
{
|
|
// check if this is the initial position computation
|
|
if (this->get_time_offset_s() == 0)
|
|
{
|
|
// execute Bancroft's algorithm to estimate initial receiver position and time
|
|
DLOG(INFO) << " Executing Bancroft algorithm...";
|
|
rx_position_and_time = bancroftPos(satpos.t(), obs);
|
|
this->set_rx_pos(rx_position_and_time.rows(0, 2)); // save ECEF position for the next iteration
|
|
this->set_time_offset_s(rx_position_and_time(3) / GPS_C_m_s); // save time for the next iteration [meters]->[seconds]
|
|
}
|
|
|
|
// Execute WLS using previous position as the initialization point
|
|
rx_position_and_time = leastSquarePos(satpos, obs, W);
|
|
|
|
this->set_rx_pos(rx_position_and_time.rows(0, 2)); // save ECEF position for the next iteration
|
|
this->set_time_offset_s(this->get_time_offset_s() + rx_position_and_time(3) / GPS_C_m_s); // accumulate the rx time error for the next iteration [meters]->[seconds]
|
|
|
|
DLOG(INFO) << "Hybrid Position at TOW=" << hybrid_current_time << " in ECEF (X,Y,Z,t[meters]) = " << rx_position_and_time;
|
|
DLOG(INFO) << "Accumulated rx clock error=" << this->get_time_offset_s() << " clock error for this iteration=" << rx_position_and_time(3) / GPS_C_m_s << " [s]";
|
|
|
|
// Compute GST and Gregorian time
|
|
if (GST != 0.0)
|
|
{
|
|
utc = galileo_utc_model.GST_to_UTC_time(GST, Galileo_week_number);
|
|
}
|
|
else
|
|
{
|
|
utc = gps_utc_model.utc_time(TX_time_corrected_s, GPS_week) + secondsperweek * static_cast<double>(GPS_week);
|
|
}
|
|
|
|
// get time string Gregorian calendar
|
|
boost::posix_time::time_duration t = boost::posix_time::seconds(utc);
|
|
// 22 August 1999 00:00 last Galileo start GST epoch (ICD sec 5.1.2)
|
|
boost::posix_time::ptime p_time(boost::gregorian::date(1999, 8, 22), t);
|
|
this->set_position_UTC_time(p_time);
|
|
|
|
cart2geo(static_cast<double>(rx_position_and_time(0)), static_cast<double>(rx_position_and_time(1)), static_cast<double>(rx_position_and_time(2)), 4);
|
|
|
|
DLOG(INFO) << "Hybrid Position at " << boost::posix_time::to_simple_string(p_time)
|
|
<< " is Lat = " << this->get_latitude() << " [deg], Long = " << this->get_longitude()
|
|
<< " [deg], Height= " << this->get_height() << " [m]"
|
|
<< " RX time offset= " << this->get_time_offset_s() << " [s]";
|
|
|
|
// ######## LOG FILE #########
|
|
if (d_flag_dump_enabled == true)
|
|
{
|
|
// MULTIPLEXED FILE RECORDING - Record results to file
|
|
try
|
|
{
|
|
double tmp_double;
|
|
// PVT GPS time
|
|
tmp_double = hybrid_current_time;
|
|
d_dump_file.write(reinterpret_cast<char*>(&tmp_double), sizeof(double));
|
|
// ECEF User Position East [m]
|
|
tmp_double = rx_position_and_time(0);
|
|
d_dump_file.write(reinterpret_cast<char*>(&tmp_double), sizeof(double));
|
|
// ECEF User Position North [m]
|
|
tmp_double = rx_position_and_time(1);
|
|
d_dump_file.write(reinterpret_cast<char*>(&tmp_double), sizeof(double));
|
|
// ECEF User Position Up [m]
|
|
tmp_double = rx_position_and_time(2);
|
|
d_dump_file.write(reinterpret_cast<char*>(&tmp_double), sizeof(double));
|
|
// User clock offset [s]
|
|
tmp_double = rx_position_and_time(3);
|
|
d_dump_file.write(reinterpret_cast<char*>(&tmp_double), sizeof(double));
|
|
// GEO user position Latitude [deg]
|
|
tmp_double = this->get_latitude();
|
|
d_dump_file.write(reinterpret_cast<char*>(&tmp_double), sizeof(double));
|
|
// GEO user position Longitude [deg]
|
|
tmp_double = this->get_longitude();
|
|
d_dump_file.write(reinterpret_cast<char*>(&tmp_double), sizeof(double));
|
|
// GEO user position Height [m]
|
|
tmp_double = this->get_height();
|
|
d_dump_file.write(reinterpret_cast<char*>(&tmp_double), sizeof(double));
|
|
}
|
|
catch (const std::ifstream::failure& e)
|
|
{
|
|
LOG(WARNING) << "Exception writing PVT LS dump file " << e.what();
|
|
}
|
|
}
|
|
|
|
// MOVING AVERAGE PVT
|
|
this->perform_pos_averaging();
|
|
}
|
|
catch (const std::exception& e)
|
|
{
|
|
this->set_time_offset_s(0.0); //reset rx time estimation
|
|
LOG(WARNING) << "Problem with the solver, invalid solution!" << e.what();
|
|
this->set_valid_position(false);
|
|
}
|
|
}
|
|
else
|
|
{
|
|
this->set_valid_position(false);
|
|
}
|
|
return this->is_valid_position();
|
|
}
|