mirror of https://github.com/gnss-sdr/gnss-sdr
682 lines
26 KiB
C++
682 lines
26 KiB
C++
/*!
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* \file gps_l1_ca_ls_pvt.cc
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* \brief Implementation of a Least Squares Position, Velocity, and Time
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* (PVT) solver, based on K.Borre's Matlab receiver.
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* \author Javier Arribas, 2011. jarribas(at)cttc.es
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* -------------------------------------------------------------------------
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*
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* Copyright (C) 2010-2012 (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 <armadillo>
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#include "gps_l1_ca_ls_pvt.h"
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#include "GPS_L1_CA.h"
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#include <glog/log_severity.h>
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#include <glog/logging.h>
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#include "boost/date_time/posix_time/posix_time.hpp"
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#include "gnss_synchro.h"
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using google::LogMessage;
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gps_l1_ca_ls_pvt::gps_l1_ca_ls_pvt(int nchannels,std::string dump_filename, bool flag_dump_to_file)
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{
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// init empty ephemeris for all the available GNSS channels
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d_nchannels = nchannels;
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d_ephemeris = new Gps_Navigation_Message[nchannels];
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d_dump_filename = dump_filename;
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d_flag_dump_enabled = flag_dump_to_file;
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d_averaging_depth = 0;
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d_GPS_current_time = 0;
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b_valid_position = false;
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// ############# ENABLE DATA FILE LOG #################
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if (d_flag_dump_enabled == 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_file.exceptions (std::ifstream::failbit | std::ifstream::badbit);
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d_dump_file.open(d_dump_filename.c_str(), std::ios::out | std::ios::binary);
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std::cout << "PVT lib dump enabled Log file: " << d_dump_filename.c_str() << std::endl;
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}
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catch (std::ifstream::failure e)
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{
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std::cout << "Exception opening PVT lib dump file " << e.what() << std::endl;
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}
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}
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}
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}
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void gps_l1_ca_ls_pvt::set_averaging_depth(int depth)
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{
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d_averaging_depth = depth;
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}
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gps_l1_ca_ls_pvt::~gps_l1_ca_ls_pvt()
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{
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d_dump_file.close();
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delete[] d_ephemeris;
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}
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arma::vec gps_l1_ca_ls_pvt::rotateSatellite(double traveltime, arma::vec X_sat)
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{
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/*
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* Returns rotated satellite ECEF coordinates due to Earth
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* rotation during signal travel time
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*
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* Inputs:
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* travelTime - signal travel time
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* X_sat - satellite's ECEF coordinates
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*
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* Returns:
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* X_sat_rot - rotated satellite's coordinates (ECEF)
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*/
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//--- Find rotation angle --------------------------------------------------
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double omegatau;
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omegatau = OMEGA_EARTH_DOT * traveltime;
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//--- Build a rotation matrix ----------------------------------------------
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arma::mat R3 = arma::zeros(3,3);
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R3(0, 0) = cos(omegatau);
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R3(0, 1) = sin(omegatau);
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R3(0, 2) = 0.0;
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R3(1, 0) = -sin(omegatau);
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R3(1, 1) = cos(omegatau);
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R3(1, 2) = 0.0;
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R3(2, 0) = 0.0;
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R3(2, 1) = 0.0;
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R3(2, 2) = 1;
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//--- Do the rotation ------------------------------------------------------
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arma::vec X_sat_rot;
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X_sat_rot = R3 * X_sat;
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return X_sat_rot;
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}
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arma::vec gps_l1_ca_ls_pvt::leastSquarePos(arma::mat satpos, arma::vec obs, arma::mat w)
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{
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/* Computes the Least Squares Solution.
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* Inputs:
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* satpos - Satellites positions in ECEF system: [X; Y; Z;]
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* obs - Observations - the pseudorange measurements to each satellite
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* w - weigths vector
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*
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* Returns:
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* pos - receiver position and receiver clock error
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* (in ECEF system: [X, Y, Z, dt])
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*/
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//=== Initialization =======================================================
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int nmbOfIterations = 10; // TODO: include in config
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int nmbOfSatellites;
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nmbOfSatellites = satpos.n_cols; //Armadillo
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arma::vec pos = "0.0 0.0 0.0 0.0";
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arma::mat A;
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arma::mat omc;
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arma::mat az;
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arma::mat el;
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A = arma::zeros(nmbOfSatellites, 4);
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omc = arma::zeros(nmbOfSatellites, 1);
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az = arma::zeros(1, nmbOfSatellites);
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el = arma::zeros(1, nmbOfSatellites);
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for (int i = 0; i < nmbOfSatellites; i++)
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{
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for (int j = 0; j < 4; j++)
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{
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A(i, j) = 0.0; //Armadillo
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}
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omc(i, 0) = 0.0;
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az(0, i) = 0.0;
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}
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el = az;
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arma::mat X = satpos;
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arma::vec Rot_X;
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double rho2;
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double traveltime;
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double trop;
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arma::mat mat_tmp;
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arma::vec x;
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//=== Iteratively find receiver position ===================================
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for (int iter = 0; iter < nmbOfIterations; iter++)
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{
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for (int i = 0; i < nmbOfSatellites; i++)
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{
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if (iter == 0)
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{
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//--- Initialize variables at the first iteration --------------
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Rot_X = X.col(i); //Armadillo
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trop = 0.0;
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}
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else
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{
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//--- Update equations -----------------------------------------
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rho2 = (X(0, i) - pos(0)) *
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(X(0, i) - pos(0)) + (X(1, i) - pos(1)) *
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(X(1, i) - pos(1)) + (X(2,i) - pos(2)) *
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(X(2,i) - pos(2));
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traveltime = sqrt(rho2) / GPS_C_m_s;
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//--- Correct satellite position (do to earth rotation) --------
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Rot_X = rotateSatellite(traveltime, X.col(i)); //armadillo
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//--- Find DOA and range of satellites
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topocent(&d_visible_satellites_Az[i], &d_visible_satellites_El[i],
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&d_visible_satellites_Distance[i], pos.subvec(0,2), Rot_X - pos.subvec(0,2));
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//[az(i), el(i), dist] = topocent(pos(1:3, :), Rot_X - pos(1:3, :));
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}
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//--- Apply the corrections ----------------------------------------
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omc(i) = (obs(i) - norm(Rot_X - pos.subvec(0,2),2) - pos(3) - trop); // Armadillo
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//--- Construct the A matrix ---------------------------------------
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//Armadillo
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A(i,0) = (-(Rot_X(0) - pos(0))) / obs(i);
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A(i,1) = (-(Rot_X(1) - pos(1))) / obs(i);
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A(i,2) = (-(Rot_X(2) - pos(2))) / obs(i);
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A(i,3) = 1.0;
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}
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//--- Find position update ---------------------------------------------
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x = arma::solve(w*A, w*omc); // Armadillo
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//--- Apply position update --------------------------------------------
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pos = pos + x;
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if (arma::norm(x,2)<1e-4)
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{
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break; // exit the loop because we assume that the LS algorithm has converged (err < 0.1 cm)
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}
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}
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try
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{
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//-- compute the Dilution Of Precision values
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arma::mat Q;
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Q = arma::inv(arma::htrans(A)*A);
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d_GDOP = sqrt(arma::trace(Q)); // Geometric DOP
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d_PDOP = sqrt(Q(0,0) + Q(1,1) + Q(2,2)); // PDOP
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d_HDOP = sqrt(Q(0,0) + Q(1,1)); // HDOP
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d_VDOP = sqrt(Q(2,2)); // VDOP
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d_TDOP = sqrt(Q(3,3)); // TDOP
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}
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catch(std::exception e)
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{
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d_GDOP = -1;
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d_PDOP = -1;
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d_HDOP = -1;
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d_VDOP = -1;
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d_TDOP = -1;
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}
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return pos;
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}
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bool gps_l1_ca_ls_pvt::get_PVT(std::map<int,Gnss_Synchro> gnss_pseudoranges_map, double GPS_current_time, bool flag_averaging)
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{
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std::map<int,Gnss_Synchro>::iterator gnss_pseudoranges_iter;
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std::map<int,Gps_Ephemeris>::iterator gps_ephemeris_iter;
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int valid_pseudoranges = gnss_pseudoranges_map.size();
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arma::mat W = arma::eye(valid_pseudoranges,valid_pseudoranges); //channels weights matrix
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arma::vec obs = arma::zeros(valid_pseudoranges); // pseudoranges observation vector
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arma::mat satpos = arma::zeros(3,valid_pseudoranges); //satellite positions matrix
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int GPS_week = 0;
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double utc = 0;
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double SV_clock_drift_s = 0;
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double SV_relativistic_clock_corr_s = 0;
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double TX_time_corrected_s;
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double SV_clock_bias_s = 0;
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d_flag_averaging = flag_averaging;
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// ********************************************************************************
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// ****** PREPARE THE LEAST SQUARES DATA (SV POSITIONS MATRIX AND OBS VECTORS) ****
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// ********************************************************************************
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int valid_obs = 0; //valid observations counter
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int obs_counter = 0;
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for(gnss_pseudoranges_iter = gnss_pseudoranges_map.begin();
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gnss_pseudoranges_iter != gnss_pseudoranges_map.end();
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gnss_pseudoranges_iter++)
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{
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// 1- find the ephemeris for the current SV observation. The SV PRN ID is the map key
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gps_ephemeris_iter = gps_ephemeris_map.find(gnss_pseudoranges_iter->first);
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if (gps_ephemeris_iter != gps_ephemeris_map.end())
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{
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/*!
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* \todo Place here the satellite CN0 (power level, or weight factor)
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*/
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W(obs_counter, obs_counter) = 1;
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// COMMON RX TIME PVT ALGORITHM MODIFICATION (Like RINEX files)
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// first estimate of transmit time
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double Rx_time = GPS_current_time;
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double Tx_time = Rx_time - gnss_pseudoranges_iter->second.Pseudorange_m/GPS_C_m_s;
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// 2- compute the clock drift using the clock model (broadcast) for this SV
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SV_clock_drift_s = gps_ephemeris_iter->second.sv_clock_drift(Tx_time);
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// 3- compute the relativistic clock drift using the clock model (broadcast) for this SV
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SV_relativistic_clock_corr_s = gps_ephemeris_iter->second.sv_clock_relativistic_term(Tx_time);
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// 4- compute the current ECEF position for this SV using corrected TX time
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SV_clock_bias_s = SV_clock_drift_s + SV_relativistic_clock_corr_s - gps_ephemeris_iter->second.d_TGD;
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TX_time_corrected_s = Tx_time - SV_clock_bias_s;
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gps_ephemeris_iter->second.satellitePosition(TX_time_corrected_s);
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satpos(0,obs_counter) = gps_ephemeris_iter->second.d_satpos_X;
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satpos(1,obs_counter) = gps_ephemeris_iter->second.d_satpos_Y;
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satpos(2,obs_counter) = gps_ephemeris_iter->second.d_satpos_Z;
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// 5- fill the observations vector with the corrected pseudorranges
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obs(obs_counter) = gnss_pseudoranges_iter->second.Pseudorange_m + SV_clock_bias_s*GPS_C_m_s;
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d_visible_satellites_IDs[valid_obs] = gps_ephemeris_iter->second.i_satellite_PRN;
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d_visible_satellites_CN0_dB[valid_obs] = gnss_pseudoranges_iter->second.CN0_dB_hz;
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valid_obs++;
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// SV ECEF DEBUG OUTPUT
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DLOG(INFO) << "(new)ECEF satellite SV ID=" << gps_ephemeris_iter->second.i_satellite_PRN
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<< " X=" << gps_ephemeris_iter->second.d_satpos_X
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<< " [m] Y=" << gps_ephemeris_iter->second.d_satpos_Y
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<< " [m] Z=" << gps_ephemeris_iter->second.d_satpos_Z
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<< " [m] PR_obs=" << obs(obs_counter) << " [m]" << std::endl;
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// compute the UTC time for this SV (just to print the asociated UTC timestamp)
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GPS_week = gps_ephemeris_iter->second.i_GPS_week;
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utc = gps_utc_model.utc_time(TX_time_corrected_s, GPS_week);
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}
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else // the ephemeris are not available for this SV
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{
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// no valid pseudorange for the current SV
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W(obs_counter, obs_counter) = 0; // SV de-activated
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obs(obs_counter) = 1; // to avoid algorithm problems (divide by zero)
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DLOG(INFO) << "No ephemeris data for SV "<< gnss_pseudoranges_iter->first << std::endl;
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}
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obs_counter++;
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}
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// ********************************************************************************
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// ****** SOLVE LEAST SQUARES******************************************************
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// ********************************************************************************
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d_valid_observations = valid_obs;
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DLOG(INFO) << "(new)PVT: valid observations=" << valid_obs << std::endl;
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if (valid_obs >= 4)
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{
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arma::vec mypos;
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DLOG(INFO) << "satpos=" << satpos << std::endl;
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DLOG(INFO) << "obs="<< obs << std::endl;
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DLOG(INFO) << "W=" << W <<std::endl;
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mypos = leastSquarePos(satpos, obs, W);
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DLOG(INFO) << "(new)Position at TOW=" << GPS_current_time << " in ECEF (X,Y,Z) = " << mypos << std::endl;
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gps_l1_ca_ls_pvt::cart2geo(mypos(0), mypos(1), mypos(2), 4);
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// Compute UTC time and print PVT solution
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double secondsperweek = 604800.0; // number of seconds in one week (7*24*60*60)
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boost::posix_time::time_duration t = boost::posix_time::seconds(utc + secondsperweek*(double)GPS_week);
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// 22 August 1999 last GPS time roll over
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boost::posix_time::ptime p_time(boost::gregorian::date(1999, 8, 22), t);
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d_position_UTC_time = p_time;
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DLOG(INFO) << "(new)Position at " << boost::posix_time::to_simple_string(p_time)
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<< " is Lat = " << d_latitude_d << " [deg], Long = " << d_longitude_d
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<< " [deg], Height= " << d_height_m << " [m]" << std::endl;
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// ######## LOG FILE #########
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if(d_flag_dump_enabled == 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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// PVT GPS time
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tmp_double = GPS_current_time;
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d_dump_file.write((char*)&tmp_double, sizeof(double));
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// ECEF User Position East [m]
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tmp_double = mypos(0);
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d_dump_file.write((char*)&tmp_double, sizeof(double));
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// ECEF User Position North [m]
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tmp_double = mypos(1);
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d_dump_file.write((char*)&tmp_double, sizeof(double));
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// ECEF User Position Up [m]
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tmp_double = mypos(2);
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d_dump_file.write((char*)&tmp_double, sizeof(double));
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// User clock offset [s]
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tmp_double = mypos(3);
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d_dump_file.write((char*)&tmp_double, sizeof(double));
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// GEO user position Latitude [deg]
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tmp_double = d_latitude_d;
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d_dump_file.write((char*)&tmp_double, sizeof(double));
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// GEO user position Longitude [deg]
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tmp_double = d_longitude_d;
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d_dump_file.write((char*)&tmp_double, sizeof(double));
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// GEO user position Height [m]
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tmp_double = d_height_m;
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d_dump_file.write((char*)&tmp_double, sizeof(double));
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}
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catch (std::ifstream::failure e)
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{
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std::cout << "Exception writing PVT LS dump file "<< e.what() << std::endl;
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}
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}
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// MOVING AVERAGE PVT
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if (flag_averaging == true)
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{
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if (d_hist_longitude_d.size() == (unsigned int)d_averaging_depth)
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{
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// Pop oldest value
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d_hist_longitude_d.pop_back();
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d_hist_latitude_d.pop_back();
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d_hist_height_m.pop_back();
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// Push new values
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d_hist_longitude_d.push_front(d_longitude_d);
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d_hist_latitude_d.push_front(d_latitude_d);
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d_hist_height_m.push_front(d_height_m);
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d_avg_latitude_d = 0;
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d_avg_longitude_d = 0;
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d_avg_height_m = 0;
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for (unsigned int i=0; i<d_hist_longitude_d.size(); i++)
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{
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d_avg_latitude_d = d_avg_latitude_d + d_hist_latitude_d.at(i);
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d_avg_longitude_d = d_avg_longitude_d + d_hist_longitude_d.at(i);
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d_avg_height_m = d_avg_height_m + d_hist_height_m.at(i);
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}
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d_avg_latitude_d = d_avg_latitude_d / (double)d_averaging_depth;
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d_avg_longitude_d = d_avg_longitude_d / (double)d_averaging_depth;
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d_avg_height_m = d_avg_height_m / (double)d_averaging_depth;
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b_valid_position = true;
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return true; //indicates that the returned position is valid
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}
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else
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{
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//int current_depth=d_hist_longitude_d.size();
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// Push new values
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d_hist_longitude_d.push_front(d_longitude_d);
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d_hist_latitude_d.push_front(d_latitude_d);
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d_hist_height_m.push_front(d_height_m);
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d_avg_latitude_d = d_latitude_d;
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d_avg_longitude_d = d_longitude_d;
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d_avg_height_m = d_height_m;
|
|
b_valid_position = false;
|
|
return false; //indicates that the returned position is not valid yet
|
|
}
|
|
}
|
|
else
|
|
{
|
|
b_valid_position = true;
|
|
return true; //indicates that the returned position is valid
|
|
}
|
|
}
|
|
else
|
|
{
|
|
b_valid_position = false;
|
|
return false;
|
|
}
|
|
}
|
|
|
|
|
|
void gps_l1_ca_ls_pvt::cart2geo(double X, double Y, double Z, int elipsoid_selection)
|
|
{
|
|
/* Conversion of Cartesian coordinates (X,Y,Z) to geographical
|
|
coordinates (latitude, longitude, h) on a selected reference ellipsoid.
|
|
|
|
Choices of Reference Ellipsoid for Geographical Coordinates
|
|
0. International Ellipsoid 1924
|
|
1. International Ellipsoid 1967
|
|
2. World Geodetic System 1972
|
|
3. Geodetic Reference System 1980
|
|
4. World Geodetic System 1984
|
|
*/
|
|
|
|
const double a[5] = {6378388, 6378160, 6378135, 6378137, 6378137};
|
|
const double f[5] = {1/297, 1/298.247, 1/298.26, 1/298.257222101, 1/298.257223563};
|
|
|
|
double lambda = atan2(Y,X);
|
|
double ex2 = (2 - f[elipsoid_selection]) * f[elipsoid_selection] / ((1 - f[elipsoid_selection])*(1 -f[elipsoid_selection]));
|
|
double c = a[elipsoid_selection] * sqrt(1+ex2);
|
|
double phi = atan(Z / ((sqrt(X*X + Y*Y)*(1 - (2 - f[elipsoid_selection])) * f[elipsoid_selection])));
|
|
|
|
double h = 0.1;
|
|
double oldh = 0;
|
|
double N;
|
|
int iterations = 0;
|
|
do
|
|
{
|
|
oldh = h;
|
|
N = c / sqrt(1 + ex2 * (cos(phi) * cos(phi)));
|
|
phi = atan(Z / ((sqrt(X*X + Y*Y) * (1 - (2 -f[elipsoid_selection]) * f[elipsoid_selection] *N / (N + h) ))));
|
|
h = sqrt(X*X + Y*Y) / cos(phi) - N;
|
|
iterations = iterations + 1;
|
|
if (iterations > 100)
|
|
{
|
|
std::cout << "Failed to approximate h with desired precision. h-oldh= " << h - oldh << std::endl;
|
|
break;
|
|
}
|
|
}
|
|
while (abs(h - oldh) > 1.0e-12);
|
|
d_latitude_d = phi * 180.0 / GPS_PI;
|
|
d_longitude_d = lambda * 180 / GPS_PI;
|
|
d_height_m = h;
|
|
}
|
|
|
|
|
|
void gps_l1_ca_ls_pvt::togeod(double *dphi, double *dlambda, double *h, double a, double finv, double X, double Y, double Z)
|
|
{
|
|
/* Subroutine to calculate geodetic coordinates latitude, longitude,
|
|
height given Cartesian coordinates X,Y,Z, and reference ellipsoid
|
|
values semi-major axis (a) and the inverse of flattening (finv).
|
|
|
|
The output units of angular quantities will be in decimal degrees
|
|
(15.5 degrees not 15 deg 30 min). The output units of h will be the
|
|
same as the units of X,Y,Z,a.
|
|
|
|
Inputs:
|
|
a - semi-major axis of the reference ellipsoid
|
|
finv - inverse of flattening of the reference ellipsoid
|
|
X,Y,Z - Cartesian coordinates
|
|
|
|
Outputs:
|
|
dphi - latitude
|
|
dlambda - longitude
|
|
h - height above reference ellipsoid
|
|
|
|
Based in a Matlab function by Kai Borre
|
|
*/
|
|
|
|
*h = 0;
|
|
double tolsq = 1.e-10; // tolerance to accept convergence
|
|
int maxit = 10; // max number of iterations
|
|
double rtd = 180/GPS_PI;
|
|
|
|
// compute square of eccentricity
|
|
double esq;
|
|
if (finv < 1.0E-20)
|
|
{
|
|
esq = 0;
|
|
}
|
|
else
|
|
{
|
|
esq = (2 - 1/finv) / finv;
|
|
}
|
|
|
|
// first guess
|
|
|
|
double P = sqrt(X*X + Y*Y); // P is distance from spin axis
|
|
//direct calculation of longitude
|
|
if (P > 1.0E-20)
|
|
{
|
|
*dlambda = atan2(Y,X) * rtd;
|
|
}
|
|
else
|
|
{
|
|
*dlambda = 0;
|
|
}
|
|
// correct longitude bound
|
|
if (*dlambda < 0)
|
|
{
|
|
*dlambda = *dlambda + 360.0;
|
|
}
|
|
double r = sqrt(P*P + Z*Z); // r is distance from origin (0,0,0)
|
|
|
|
double sinphi;
|
|
if (r > 1.0E-20)
|
|
{
|
|
sinphi = Z/r;
|
|
}
|
|
else
|
|
{
|
|
sinphi = 0;
|
|
}
|
|
*dphi = asin(sinphi);
|
|
|
|
// initial value of height = distance from origin minus
|
|
// approximate distance from origin to surface of ellipsoid
|
|
if (r < 1.0E-20)
|
|
{
|
|
*h = 0;
|
|
return;
|
|
}
|
|
|
|
*h = r - a*(1-sinphi*sinphi/finv);
|
|
|
|
// iterate
|
|
double cosphi;
|
|
double N_phi;
|
|
double dP;
|
|
double dZ;
|
|
double oneesq = 1 - esq;
|
|
|
|
for (int i=0; i<maxit; i++)
|
|
{
|
|
sinphi = sin(*dphi);
|
|
cosphi = cos(*dphi);
|
|
|
|
// compute radius of curvature in prime vertical direction
|
|
N_phi = a / sqrt(1 - esq*sinphi*sinphi);
|
|
|
|
// compute residuals in P and Z
|
|
dP = P - (N_phi + (*h)) * cosphi;
|
|
dZ = Z - (N_phi*oneesq + (*h)) * sinphi;
|
|
|
|
// update height and latitude
|
|
*h = *h + (sinphi*dZ + cosphi*dP);
|
|
*dphi = *dphi + (cosphi*dZ - sinphi*dP)/(N_phi + (*h));
|
|
|
|
// test for convergence
|
|
if ((dP*dP + dZ*dZ) < tolsq)
|
|
{
|
|
break;
|
|
}
|
|
if (i == (maxit-1))
|
|
{
|
|
DLOG(INFO) << "The computation of geodetic coordinates did not converge";
|
|
}
|
|
}
|
|
*dphi = (*dphi) * rtd;
|
|
}
|
|
|
|
|
|
void gps_l1_ca_ls_pvt::topocent(double *Az, double *El, double *D, arma::vec x, arma::vec dx)
|
|
{
|
|
/* Transformation of vector dx into topocentric coordinate
|
|
system with origin at x
|
|
Inputs:
|
|
x - vector origin coordinates (in ECEF system [X; Y; Z;])
|
|
dx - vector ([dX; dY; dZ;]).
|
|
|
|
Outputs:
|
|
D - vector length. Units like the input
|
|
Az - azimuth from north positive clockwise, degrees
|
|
El - elevation angle, degrees
|
|
|
|
Based on a Matlab function by Kai Borre
|
|
*/
|
|
|
|
double lambda;
|
|
double phi;
|
|
double h;
|
|
double dtr = GPS_PI/180.0;
|
|
double a = 6378137.0; // semi-major axis of the reference ellipsoid WGS-84
|
|
double finv = 298.257223563; // inverse of flattening of the reference ellipsoid WGS-84
|
|
|
|
// Transform x into geodetic coordinates
|
|
togeod(&phi, &lambda, &h, a, finv, x(0), x(1), x(2));
|
|
|
|
double cl = cos(lambda * dtr);
|
|
double sl = sin(lambda * dtr);
|
|
double cb = cos(phi * dtr);
|
|
double sb = sin(phi * dtr);
|
|
|
|
arma::mat F = arma::zeros(3,3);
|
|
|
|
F(0,0) = -sl;
|
|
F(0,1) = -sb*cl;
|
|
F(0,2) = cb*cl;
|
|
|
|
F(1,0) = cl;
|
|
F(1,1) = -sb*sl;
|
|
F(1,2) = cb*sl;
|
|
|
|
F(2,0) = 0;
|
|
F(2,1) = cb;
|
|
F(2,2) = sb;
|
|
|
|
arma::vec local_vector;
|
|
|
|
local_vector = arma::htrans(F) * dx;
|
|
|
|
double E = local_vector(0);
|
|
double N = local_vector(1);
|
|
double U = local_vector(2);
|
|
|
|
double hor_dis;
|
|
hor_dis = sqrt(E*E + N*N);
|
|
|
|
if (hor_dis < 1.0E-20)
|
|
{
|
|
*Az = 0;
|
|
*El = 90;
|
|
}
|
|
else
|
|
{
|
|
*Az = atan2(E, N)/dtr;
|
|
*El = atan2(U, hor_dis)/dtr;
|
|
}
|
|
|
|
if (*Az < 0)
|
|
{
|
|
*Az = *Az + 360.0;
|
|
}
|
|
|
|
*D = sqrt(dx(0)*dx(0) + dx(1)*dx(1) + dx(2)*dx(2));
|
|
}
|