mirror of https://github.com/gnss-sdr/gnss-sdr
1188 lines
37 KiB
C++
1188 lines
37 KiB
C++
/*!
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* \file rtklib_pntpos.cc
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* \brief standard code-based positioning
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* \authors <ul>
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* <li> 2007-2013, T. Takasu
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* <li> 2017, Javier Arribas
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* <li> 2017, Carles Fernandez
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* </ul>
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*
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* This is a derived work from RTKLIB http://www.rtklib.com/
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* The original source code at https://github.com/tomojitakasu/RTKLIB is
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* released under the BSD 2-clause license with an additional exclusive clause
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* that does not apply here. This additional clause is reproduced below:
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*
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* " The software package includes some companion executive binaries or shared
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* libraries necessary to execute APs on Windows. These licenses succeed to the
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* original ones of these software. "
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*
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* Neither the executive binaries nor the shared libraries are required by, used
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* or included in GNSS-SDR.
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*
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* -----------------------------------------------------------------------------
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* Copyright (C) 2007-2013, T. Takasu
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* Copyright (C) 2017, Javier Arribas
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* Copyright (C) 2017-2023, Carles Fernandez
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* All rights reserved.
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*
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* SPDX-License-Identifier: BSD-2-Clause
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* -----------------------------------------------------------------------------
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*/
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#include "rtklib_pntpos.h"
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#include "rtklib_ephemeris.h"
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#include "rtklib_ionex.h"
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#include "rtklib_sbas.h"
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#include <armadillo>
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#include <cmath>
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#include <cstring>
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#include <vector>
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/* pseudorange measurement error variance ------------------------------------*/
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double varerr(const prcopt_t *opt, double el, int sys)
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{
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double fact;
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double varr;
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fact = sys == SYS_GLO ? EFACT_GLO : (sys == SYS_SBS ? EFACT_SBS : EFACT_GPS);
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varr = std::pow(opt->err[0], 2.0) * (std::pow(opt->err[1], 2.0) + std::pow(opt->err[2], 2.0) / sin(el));
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if (opt->ionoopt == IONOOPT_IFLC)
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{
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varr *= std::pow(2, 3.0); /* iono-free */
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}
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return std::pow(fact, 2.0) * varr;
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}
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/* get tgd parameter (m) -----------------------------------------------------*/
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double gettgd(int sat, const nav_t *nav)
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{
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int i;
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for (i = 0; i < nav->n; i++)
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{
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if (nav->eph[i].sat != sat)
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{
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continue;
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}
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return SPEED_OF_LIGHT_M_S * nav->eph[i].tgd[0];
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}
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return 0.0;
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}
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/* get isc parameter (m) -----------------------------------------------------*/
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double getiscl1(int sat, const nav_t *nav)
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{
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for (int i = 0; i < nav->n; i++)
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{
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if (nav->eph[i].sat != sat)
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{
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continue;
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}
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return SPEED_OF_LIGHT_M_S * nav->eph[i].isc[0];
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}
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return 0.0;
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}
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double getiscl2(int sat, const nav_t *nav)
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{
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for (int i = 0; i < nav->n; i++)
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{
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if (nav->eph[i].sat != sat)
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{
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continue;
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}
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return SPEED_OF_LIGHT_M_S * nav->eph[i].isc[1];
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}
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return 0.0;
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}
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double getiscl5i(int sat, const nav_t *nav)
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{
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for (int i = 0; i < nav->n; i++)
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{
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if (nav->eph[i].sat != sat)
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{
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continue;
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}
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return SPEED_OF_LIGHT_M_S * nav->eph[i].isc[2];
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}
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return 0.0;
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}
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double getiscl5q(int sat, const nav_t *nav)
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{
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for (int i = 0; i < nav->n; i++)
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{
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if (nav->eph[i].sat != sat)
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{
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continue;
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}
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return SPEED_OF_LIGHT_M_S * nav->eph[i].isc[3];
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}
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return 0.0;
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}
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/* psendorange with code bias correction -------------------------------------*/
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double prange(const obsd_t *obs, const nav_t *nav, const double *azel,
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int iter, const prcopt_t *opt, double *var)
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{
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const double *lam = nav->lam[obs->sat - 1];
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double PC = 0.0;
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double P1 = 0.0;
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double P2 = 0.0;
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double P1_P2 = 0.0;
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double P1_C1 = 0.0;
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double P2_C2 = 0.0;
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// Intersignal corrections (m). See GPS IS-200 CNAV message
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// double ISCl1 = 0.0;
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double ISCl2 = 0.0;
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double ISCl5i = 0.0;
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// double ISCl5q = 0.0;
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double gamma_ = 0.0;
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int i = 0;
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int j = 1;
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int sys = satsys(obs->sat, nullptr);
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*var = 0.0;
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if (sys == SYS_NONE)
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{
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trace(4, "prange: satsys NULL\n");
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return 0.0;
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}
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/* L1-L2 for GPS/GLO/QZS, L1-L5 for GAL/SBS/BDS */
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if (sys == SYS_GAL or sys == SYS_SBS or sys == SYS_BDS)
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{
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j = 2;
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}
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else if (sys == SYS_GPS or sys == SYS_GLO)
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{
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if (obs->code[1] != CODE_NONE)
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{
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j = 1;
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}
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else if (obs->code[2] != CODE_NONE)
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{
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j = 2;
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}
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}
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if (lam[i] == 0.0 or lam[j] == 0.0)
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{
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trace(4, "prange: NFREQ<2||lam[i]==0.0||lam[j]==0.0\n");
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printf("i: %d j:%d, lam[i]: %f lam[j] %f\n", i, j, lam[i], lam[j]);
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return 0.0;
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}
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/* test snr mask */
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if (iter > 0)
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{
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if (testsnr(0, i, azel[1], obs->SNR[i] * 0.25, &opt->snrmask))
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{
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trace(4, "snr mask: %s sat=%2d el=%.1f snr=%.1f\n",
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time_str(obs->time, 0), obs->sat, azel[1] * R2D, obs->SNR[i] * 0.25);
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return 0.0;
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}
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if (opt->ionoopt == IONOOPT_IFLC)
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{
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if (testsnr(0, j, azel[1], obs->SNR[j] * 0.25, &opt->snrmask))
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{
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trace(4, "prange: testsnr error\n");
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return 0.0;
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}
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}
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}
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/* fL1^2 / fL2(orL5)^2 . See IS-GPS-200, p. 103 and Galileo ICD p. 48 */
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if (sys == SYS_GPS or sys == SYS_GAL or sys == SYS_GLO or sys == SYS_BDS)
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{
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gamma_ = std::pow(lam[j], 2.0) / std::pow(lam[i], 2.0);
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}
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P1 = obs->P[i];
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P2 = obs->P[j];
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P1_P2 = nav->cbias[obs->sat - 1][0];
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P1_C1 = nav->cbias[obs->sat - 1][1];
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P2_C2 = nav->cbias[obs->sat - 1][2];
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/* if no P1-P2 DCB, use TGD instead */
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if (P1_P2 == 0.0)
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{
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P1_P2 = gettgd(obs->sat, nav);
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}
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if (sys == SYS_GPS)
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{
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// ISCl1 = getiscl1(obs->sat, nav);
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ISCl2 = getiscl2(obs->sat, nav);
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ISCl5i = getiscl5i(obs->sat, nav);
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// ISCl5q = getiscl5q(obs->sat, nav);
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}
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// CHECK IF IT IS STILL NEEDED
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if (opt->ionoopt == IONOOPT_IFLC)
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{
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/* dual-frequency */
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if (P1 == 0.0 || P2 == 0.0)
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{
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return 0.0;
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}
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if (obs->code[i] == CODE_L1C)
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{
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P1 += P1_C1;
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} /* C1->P1 */
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if (obs->code[j] == CODE_L2C)
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{
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P2 += P2_C2;
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} /* C2->P2 */
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/* iono-free combination */
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PC = (gamma_ * P1 - P2) / (gamma_ - 1.0);
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}
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////////////////////////////////////////////
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else
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{ /* single-frequency */
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if (obs->code[i] == CODE_NONE and obs->code[j] == CODE_NONE)
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{
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return 0.0;
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}
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if (obs->code[i] != CODE_NONE and obs->code[j] == CODE_NONE)
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{
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P1 += P1_C1; /* C1->P1 */
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PC = P1 - P1_P2;
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}
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else if (obs->code[i] == CODE_NONE and obs->code[j] != CODE_NONE)
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{
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if (sys == SYS_GPS)
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{
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P2 += P2_C2; /* C2->P2 */
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// PC = P2 - gamma_ * P1_P2 / (1.0 - gamma_);
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if (obs->code[j] == CODE_L2S) // L2 single freq.
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{
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PC = P2 + P1_P2 - ISCl2;
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}
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else if (obs->code[j] == CODE_L5X) // L5 single freq.
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{
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PC = P2 + P1_P2 - ISCl5i;
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}
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}
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if (sys == SYS_BDS)
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{
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P2 += P2_C2; /* C2->P2 */
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PC = P2; // no tgd corrections for B3I
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}
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else if (sys == SYS_GAL or sys == SYS_GLO or sys == SYS_BDS) // Gal. E5a single freq.
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{
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P2 += P2_C2; /* C2->P2 */
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PC = P2 - gamma_ * P1_P2 / (1.0 - gamma_);
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}
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}
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/* dual-frequency */
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else if (sys == SYS_GPS)
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{
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if (obs->code[j] == CODE_L2S) /* L1 + L2 */
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{
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// By the moment, GPS L2 pseudoranges are not used
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// PC = (P2 + ISCl2 - gamma_ * (P1 + ISCl1)) / (1.0 - gamma_) - P1_P2;
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P1 += P1_C1; /* C1->P1 */
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PC = P1 + P1_P2;
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}
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else if (obs->code[j] == CODE_L5X) /* L1 + L5 */
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{
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// By the moment, GPS L5 pseudoranges are not used
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// PC = (P2 + ISCl5i - gamma_ * (P1 + ISCl5i)) / (1.0 - gamma_) - P1_P2;
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P1 += P1_C1; /* C1->P1 */
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PC = P1 + P1_P2;
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}
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}
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else if (sys == SYS_GAL or sys == SYS_GLO or sys == SYS_BDS) /* E1 + E5a */
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{
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P1 += P1_C1;
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P2 += P2_C2;
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PC = (gamma_ * P1 - P2) / (gamma_ - 1.0);
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}
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}
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if (opt->sateph == EPHOPT_SBAS)
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{
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PC -= P1_C1;
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} /* sbas clock based C1 */
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*var = std::pow(ERR_CBIAS, 2.0);
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return PC;
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}
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/* ionospheric correction ------------------------------------------------------
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* compute ionospheric correction
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* args : gtime_t time I time
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* nav_t *nav I navigation data
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* int sat I satellite number
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* double *pos I receiver position {lat,lon,h} (rad|m)
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* double *azel I azimuth/elevation angle {az,el} (rad)
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* int ionoopt I ionospheric correction option (IONOOPT_???)
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* double *ion O ionospheric delay (L1) (m)
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* double *var O ionospheric delay (L1) variance (m^2)
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* return : status(1:ok,0:error)
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*-----------------------------------------------------------------------------*/
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int ionocorr(gtime_t time, const nav_t *nav, int sat, const double *pos,
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const double *azel, int ionoopt, double *ion, double *var)
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{
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trace(4, "ionocorr: time=%s opt=%d sat=%2d pos=%.3f %.3f azel=%.3f %.3f\n",
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time_str(time, 3), ionoopt, sat, pos[0] * R2D, pos[1] * R2D, azel[0] * R2D,
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azel[1] * R2D);
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/* broadcast model */
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if (ionoopt == IONOOPT_BRDC)
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{
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*ion = ionmodel(time, nav->ion_gps, pos, azel);
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*var = std::pow(*ion * ERR_BRDCI, 2.0);
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return 1;
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}
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/* sbas ionosphere model */
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if (ionoopt == IONOOPT_SBAS)
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{
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return sbsioncorr(time, nav, pos, azel, ion, var);
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}
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/* ionex tec model */
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if (ionoopt == IONOOPT_TEC)
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{
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return iontec(time, nav, pos, azel, 1, ion, var);
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}
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/* qzss broadcast model */
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if (ionoopt == IONOOPT_QZS && norm_rtk(nav->ion_qzs, 8) > 0.0)
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{
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*ion = ionmodel(time, nav->ion_qzs, pos, azel);
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*var = std::pow(*ion * ERR_BRDCI, 2.0);
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return 1;
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}
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/* lex ionosphere model */
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// if (ionoopt == IONOOPT_LEX) {
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// return lexioncorr(time, nav, pos, azel, ion, var);
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// }
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*ion = 0.0;
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*var = ionoopt == IONOOPT_OFF ? std::pow(ERR_ION, 2.0) : 0.0;
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return 1;
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}
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/* tropospheric correction -----------------------------------------------------
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* compute tropospheric correction
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* args : gtime_t time I time
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* nav_t *nav I navigation data
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* double *pos I receiver position {lat,lon,h} (rad|m)
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* double *azel I azimuth/elevation angle {az,el} (rad)
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* int tropopt I tropospheric correction option (TROPOPT_???)
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* double *trp O tropospheric delay (m)
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* double *var O tropospheric delay variance (m^2)
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* return : status(1:ok,0:error)
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*-----------------------------------------------------------------------------*/
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int tropcorr(gtime_t time, const nav_t *nav __attribute__((unused)), const double *pos,
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const double *azel, int tropopt, double *trp, double *var)
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{
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trace(4, "tropcorr: time=%s opt=%d pos=%.3f %.3f azel=%.3f %.3f\n",
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time_str(time, 3), tropopt, pos[0] * R2D, pos[1] * R2D, azel[0] * R2D,
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azel[1] * R2D);
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/* saastamoinen model */
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if (tropopt == TROPOPT_SAAS || tropopt == TROPOPT_EST || tropopt == TROPOPT_ESTG)
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{
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*trp = tropmodel(time, pos, azel, REL_HUMI);
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*var = std::pow(ERR_SAAS / (sin(azel[1]) + 0.1), 2.0);
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return 1;
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}
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/* sbas troposphere model */
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if (tropopt == TROPOPT_SBAS)
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{
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*trp = sbstropcorr(time, pos, azel, var);
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return 1;
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}
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/* no correction */
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*trp = 0.0;
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*var = tropopt == TROPOPT_OFF ? std::pow(ERR_TROP, 2.0) : 0.0;
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return 1;
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}
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/* pseudorange residuals -----------------------------------------------------*/
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int rescode(int iter, const obsd_t *obs, int n, const double *rs,
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const double *dts, const double *vare, const int *svh,
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const nav_t *nav, const double *x, const prcopt_t *opt,
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double *v, double *H, double *var, double *azel, int *vsat,
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double *resp, int *ns)
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{
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double r;
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double dion;
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double dtrp;
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double vmeas;
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double vion;
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double vtrp;
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double rr[3];
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double pos[3];
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double dtr;
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double e[3];
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double P;
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double lam_L1;
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int i;
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int j;
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int nv = 0;
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int sys;
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int mask[4] = {0};
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trace(3, "resprng : n=%d\n", n);
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for (i = 0; i < 3; i++)
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{
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rr[i] = x[i];
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}
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dtr = x[3];
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ecef2pos(rr, pos);
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for (i = *ns = 0; i < n && i < MAXOBS; i++)
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{
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vsat[i] = 0;
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azel[i * 2] = azel[1 + i * 2] = resp[i] = 0.0;
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if (!(sys = satsys(obs[i].sat, nullptr)))
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{
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continue;
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}
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/* reject duplicated observation data */
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if (i < n - 1 && i < MAXOBS - 1 && obs[i].sat == obs[i + 1].sat)
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{
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trace(2, "duplicated observation data %s sat=%2d\n",
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time_str(obs[i].time, 3), obs[i].sat);
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i++;
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continue;
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}
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/* geometric distance/azimuth/elevation angle */
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if ((r = geodist(rs + i * 6, rr, e)) <= 0.0)
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{
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trace(4, "geodist error\n");
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continue;
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}
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double elaux = satazel(pos, e, azel + i * 2);
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if (elaux < opt->elmin)
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{
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trace(4, "satazel error. el = %lf , elmin = %lf\n", elaux, opt->elmin);
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continue;
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}
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/* psudorange with code bias correction */
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if ((P = prange(obs + i, nav, azel + i * 2, iter, opt, &vmeas)) == 0.0)
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{
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trace(4, "prange error\n");
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continue;
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}
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/* excluded satellite? */
|
|
if (satexclude(obs[i].sat, svh[i], opt))
|
|
{
|
|
trace(4, "satexclude error\n");
|
|
continue;
|
|
}
|
|
|
|
/* ionospheric corrections */
|
|
if (!ionocorr(obs[i].time, nav, obs[i].sat, pos, azel + i * 2,
|
|
iter > 0 ? opt->ionoopt : IONOOPT_BRDC, &dion, &vion))
|
|
{
|
|
trace(4, "ionocorr error\n");
|
|
continue;
|
|
}
|
|
|
|
/* GPS-L1 -> L1/B1 */
|
|
if ((lam_L1 = nav->lam[obs[i].sat - 1][0]) > 0.0)
|
|
{
|
|
dion *= std::pow(lam_L1 / LAM_CARR[0], 2.0);
|
|
}
|
|
/* tropospheric corrections */
|
|
if (!tropcorr(obs[i].time, nav, pos, azel + i * 2,
|
|
iter > 0 ? opt->tropopt : TROPOPT_SAAS, &dtrp, &vtrp))
|
|
{
|
|
trace(4, "tropocorr error\n");
|
|
continue;
|
|
}
|
|
/* pseudorange residual */
|
|
v[nv] = P - (r + dtr - SPEED_OF_LIGHT_M_S * dts[i * 2] + dion + dtrp);
|
|
|
|
/* design matrix */
|
|
for (j = 0; j < NX; j++)
|
|
{
|
|
H[j + nv * NX] = j < 3 ? -e[j] : (j == 3 ? 1.0 : 0.0);
|
|
}
|
|
|
|
/* time system and receiver bias offset correction */
|
|
if (sys == SYS_GLO)
|
|
{
|
|
v[nv] -= x[4];
|
|
H[4 + nv * NX] = 1.0;
|
|
mask[1] = 1;
|
|
}
|
|
else if (sys == SYS_GAL)
|
|
{
|
|
v[nv] -= x[5];
|
|
H[5 + nv * NX] = 1.0;
|
|
mask[2] = 1;
|
|
}
|
|
else if (sys == SYS_BDS)
|
|
{
|
|
v[nv] -= x[6];
|
|
H[6 + nv * NX] = 1.0;
|
|
mask[3] = 1;
|
|
}
|
|
else
|
|
{
|
|
mask[0] = 1;
|
|
}
|
|
|
|
vsat[i] = 1;
|
|
resp[i] = v[nv];
|
|
(*ns)++;
|
|
|
|
/* error variance */
|
|
var[nv++] = varerr(opt, azel[1 + i * 2], sys) + vare[i] + vmeas + vion + vtrp;
|
|
|
|
trace(4, "sat=%2d azel=%5.1f %4.1f res=%7.3f sig=%5.3f\n", obs[i].sat,
|
|
azel[i * 2] * R2D, azel[1 + i * 2] * R2D, resp[i], sqrt(var[nv - 1]));
|
|
}
|
|
/* constraint to avoid rank-deficient */
|
|
for (i = 0; i < 4; i++)
|
|
{
|
|
if (mask[i])
|
|
{
|
|
continue;
|
|
}
|
|
v[nv] = 0.0;
|
|
for (j = 0; j < NX; j++)
|
|
{
|
|
H[j + nv * NX] = j == i + 3 ? 1.0 : 0.0;
|
|
}
|
|
var[nv++] = 0.01;
|
|
}
|
|
return nv;
|
|
}
|
|
|
|
|
|
/* validate solution ---------------------------------------------------------*/
|
|
int valsol(const double *azel, const int *vsat, int n,
|
|
const prcopt_t *opt, const double *v, int nv, int nx,
|
|
char *msg)
|
|
{
|
|
double azels[MAXOBS * 2] = {0};
|
|
double dop[4];
|
|
double vv;
|
|
int i;
|
|
int ns;
|
|
|
|
trace(3, "valsol : n=%d nv=%d\n", n, nv);
|
|
|
|
/* chi-square validation of residuals */
|
|
vv = dot(v, v, nv);
|
|
if (nv > nx && vv > CHISQR[nv - nx - 1])
|
|
{
|
|
std::snprintf(msg, MAXSOLBUF, "chi-square error nv=%d vv=%.1f cs=%.1f", nv, vv, CHISQR[nv - nx - 1]);
|
|
return 0;
|
|
}
|
|
/* large gdop check */
|
|
for (i = ns = 0; i < n; i++)
|
|
{
|
|
if (!vsat[i])
|
|
{
|
|
continue;
|
|
}
|
|
azels[ns * 2] = azel[i * 2];
|
|
azels[1 + ns * 2] = azel[1 + i * 2];
|
|
ns++;
|
|
}
|
|
dops(ns, azels, opt->elmin, dop);
|
|
if (dop[0] <= 0.0 || dop[0] > opt->maxgdop)
|
|
{
|
|
std::snprintf(msg, MAXSOLBUF, "gdop error nv=%d gdop=%.1f", nv, dop[0]);
|
|
return 0;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
|
|
// Lorentz inner product
|
|
double lorentz(const arma::vec &x, const arma::vec &y)
|
|
{
|
|
double p = x(0) * y(0) + x(1) * y(1) + x(2) * y(2) - x(3) * y(3);
|
|
return p;
|
|
}
|
|
|
|
|
|
// Bancroft method (see https://gssc.esa.int/navipedia/index.php/Bancroft_Method)
|
|
// without travel time rotation
|
|
arma::vec rough_bancroft(const arma::mat &B_pass)
|
|
{
|
|
const int m = B_pass.n_rows;
|
|
arma::vec pos = arma::zeros<arma::vec>(4);
|
|
for (int iter = 1; iter <= 2; iter++)
|
|
{
|
|
// We should rotate the matrix accounting for the travel time here,
|
|
// but for a rough first estimation we can skip it
|
|
arma::mat BBB;
|
|
bool success;
|
|
if (m > 4)
|
|
{
|
|
success = arma::inv(BBB, B_pass.t() * B_pass);
|
|
if (success)
|
|
{
|
|
BBB *= B_pass.t();
|
|
}
|
|
}
|
|
else
|
|
{
|
|
success = arma::inv(BBB, B_pass);
|
|
}
|
|
if (!success)
|
|
{
|
|
return pos;
|
|
}
|
|
const arma::vec e = arma::ones<arma::vec>(m);
|
|
arma::vec alpha = arma::zeros<arma::vec>(m);
|
|
for (int i = 0; i < m; i++)
|
|
{
|
|
arma::vec Bi = B_pass.row(i).t();
|
|
alpha(i) = lorentz(Bi, Bi) / 2.0;
|
|
}
|
|
const arma::vec BBBe = BBB * e;
|
|
const arma::vec BBBalpha = BBB * alpha;
|
|
double a = lorentz(BBBe, BBBe);
|
|
double b = lorentz(BBBe, BBBalpha) - 1.0;
|
|
double c = lorentz(BBBalpha, BBBalpha);
|
|
double root = std::sqrt(b * b - a * c);
|
|
arma::vec r(2);
|
|
r(0) = (-b - root) / a;
|
|
r(1) = (-b + root) / a;
|
|
arma::mat possible_pos = arma::zeros<arma::mat>(4, 2);
|
|
for (int i = 0; i < 2; i++)
|
|
{
|
|
possible_pos.col(i) = r(i) * BBBe + BBBalpha;
|
|
possible_pos(3, i) = -possible_pos(3, i);
|
|
}
|
|
arma::vec abs_omc(2);
|
|
for (int j = 0; j < m; j++)
|
|
{
|
|
for (int i = 0; i < 2; i++)
|
|
{
|
|
double c_dt = possible_pos(3, i);
|
|
double calc = arma::norm(B_pass.row(j).head(3).t() - possible_pos.head_rows(3).col(i)) + c_dt;
|
|
double omc = B_pass(j, 3) - calc;
|
|
abs_omc(i) = std::abs(omc);
|
|
}
|
|
}
|
|
|
|
if (abs_omc(0) > abs_omc(1))
|
|
{
|
|
pos = possible_pos.col(1);
|
|
}
|
|
else
|
|
{
|
|
pos = possible_pos.col(0);
|
|
}
|
|
}
|
|
|
|
return pos;
|
|
}
|
|
|
|
|
|
/* estimate receiver position ------------------------------------------------*/
|
|
int estpos(const obsd_t *obs, int n, const double *rs, const double *dts,
|
|
const double *vare, const int *svh, const nav_t *nav,
|
|
const prcopt_t *opt, sol_t *sol, double *azel, int *vsat,
|
|
double *resp, char *msg)
|
|
{
|
|
double x[NX] = {0};
|
|
double dx[NX];
|
|
double Q[NX * NX];
|
|
double *v;
|
|
double *H;
|
|
double *var;
|
|
double sig;
|
|
int i;
|
|
int j;
|
|
int k;
|
|
int info;
|
|
int stat;
|
|
int nv;
|
|
int ns;
|
|
char msg_aux[128];
|
|
|
|
trace(3, "estpos : n=%d\n", n);
|
|
|
|
v = mat(n + 4, 1);
|
|
H = mat(NX, n + 4);
|
|
var = mat(n + 4, 1);
|
|
|
|
for (i = 0; i < 3; i++)
|
|
{
|
|
x[i] = sol->rr[i];
|
|
}
|
|
|
|
// Rough first estimation to initialize the algorithm
|
|
if (std::sqrt(x[0] * x[0] + x[1] * x[1] + x[2] * x[2]) < 0.1)
|
|
{
|
|
arma::mat B = arma::mat(n, 4, arma::fill::zeros);
|
|
for (i = 0; i < n; i++)
|
|
{
|
|
B(i, 0) = rs[0 + i * 6];
|
|
B(i, 1) = rs[1 + i * 6];
|
|
B(i, 2) = rs[2 + i * 6];
|
|
if (obs[i].code[0] != CODE_NONE)
|
|
{
|
|
B(i, 3) = obs[i].P[0];
|
|
}
|
|
else if (obs[i].code[1] != CODE_NONE)
|
|
{
|
|
B(i, 3) = obs[i].P[1];
|
|
}
|
|
else
|
|
{
|
|
B(i, 3) = obs[i].P[2];
|
|
}
|
|
}
|
|
arma::vec pos = rough_bancroft(B);
|
|
x[0] = pos(0);
|
|
x[1] = pos(1);
|
|
x[2] = pos(2);
|
|
}
|
|
|
|
for (i = 0; i < MAXITR; i++)
|
|
{
|
|
/* pseudorange residuals */
|
|
nv = rescode(i, obs, n, rs, dts, vare, svh, nav, x, opt, v, H, var, azel, vsat, resp, &ns);
|
|
|
|
if (nv < NX)
|
|
{
|
|
std::snprintf(msg_aux, sizeof(msg_aux), "lack of valid sats ns=%d", nv);
|
|
break;
|
|
}
|
|
/* weight by variance */
|
|
for (j = 0; j < nv; j++)
|
|
{
|
|
sig = sqrt(var[j]);
|
|
v[j] /= sig;
|
|
for (k = 0; k < NX; k++)
|
|
{
|
|
H[k + j * NX] /= sig;
|
|
}
|
|
}
|
|
/* least square estimation */
|
|
if ((info = lsq(H, v, NX, nv, dx, Q)))
|
|
{
|
|
std::snprintf(msg_aux, sizeof(msg_aux), "lsq error info=%d", info);
|
|
break;
|
|
}
|
|
for (j = 0; j < NX; j++)
|
|
{
|
|
x[j] += dx[j];
|
|
}
|
|
|
|
if (norm_rtk(dx, NX) < 1e-4)
|
|
{
|
|
sol->type = 0;
|
|
sol->time = timeadd(obs[0].time, -x[3] / SPEED_OF_LIGHT_M_S);
|
|
sol->dtr[0] = x[3] / SPEED_OF_LIGHT_M_S; /* receiver clock bias (s) */
|
|
sol->dtr[1] = x[4] / SPEED_OF_LIGHT_M_S; /* glo-gps time offset (s) */
|
|
sol->dtr[2] = x[5] / SPEED_OF_LIGHT_M_S; /* gal-gps time offset (s) */
|
|
sol->dtr[3] = x[6] / SPEED_OF_LIGHT_M_S; /* bds-gps time offset (s) */
|
|
for (j = 0; j < 6; j++)
|
|
{
|
|
sol->rr[j] = j < 3 ? x[j] : 0.0;
|
|
}
|
|
for (j = 0; j < 3; j++)
|
|
{
|
|
sol->qr[j] = static_cast<float>(Q[j + j * NX]);
|
|
}
|
|
sol->qr[3] = static_cast<float>(Q[1]); /* cov xy */
|
|
sol->qr[4] = static_cast<float>(Q[2 + NX]); /* cov yz */
|
|
sol->qr[5] = static_cast<float>(Q[2]); /* cov zx */
|
|
sol->ns = static_cast<unsigned char>(ns);
|
|
sol->age = sol->ratio = 0.0;
|
|
|
|
/* validate solution */
|
|
if ((stat = valsol(azel, vsat, n, opt, v, nv, NX, msg)))
|
|
{
|
|
sol->stat = opt->sateph == EPHOPT_SBAS ? SOLQ_SBAS : SOLQ_SINGLE;
|
|
}
|
|
free(v);
|
|
free(H);
|
|
free(var);
|
|
msg = msg_aux;
|
|
return stat;
|
|
}
|
|
}
|
|
if (i >= MAXITR)
|
|
{
|
|
std::snprintf(msg_aux, sizeof(msg_aux), "iteration divergent i=%d", i);
|
|
}
|
|
|
|
free(v);
|
|
free(H);
|
|
free(var);
|
|
msg = msg_aux;
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
/* raim fde (failure detection and exclution) -------------------------------*/
|
|
int raim_fde(const obsd_t *obs, int n, const double *rs,
|
|
const double *dts, const double *vare, const int *svh,
|
|
const nav_t *nav, const prcopt_t *opt, sol_t *sol,
|
|
double *azel, int *vsat, double *resp, char *msg)
|
|
{
|
|
obsd_t *obs_e;
|
|
sol_t sol_e = {{0, 0}, {}, {}, {}, '0', '0', '0', 0.0, 0.0, 0.0};
|
|
char tstr[32];
|
|
char msg_e[128];
|
|
double *rs_e;
|
|
double *dts_e;
|
|
double *vare_e;
|
|
double *azel_e;
|
|
double *resp_e;
|
|
double rms_e;
|
|
double rms = 100.0;
|
|
int i;
|
|
int j;
|
|
int k;
|
|
int nvsat;
|
|
int stat = 0;
|
|
int *svh_e;
|
|
int *vsat_e;
|
|
int sat = 0;
|
|
|
|
trace(3, "raim_fde: %s n=%2d\n", time_str(obs[0].time, 0), n);
|
|
|
|
if (!(obs_e = static_cast<obsd_t *>(malloc(sizeof(obsd_t) * n))))
|
|
{
|
|
return 0;
|
|
}
|
|
rs_e = mat(6, n);
|
|
dts_e = mat(2, n);
|
|
vare_e = mat(1, n);
|
|
azel_e = zeros(2, n);
|
|
svh_e = imat(1, n);
|
|
vsat_e = imat(1, n);
|
|
resp_e = mat(1, n);
|
|
|
|
for (i = 0; i < n; i++)
|
|
{
|
|
/* satellite exclution */
|
|
for (j = k = 0; j < n; j++)
|
|
{
|
|
if (j == i)
|
|
{
|
|
continue;
|
|
}
|
|
obs_e[k] = obs[j];
|
|
matcpy(rs_e + 6 * k, rs + 6 * j, 6, 1);
|
|
matcpy(dts_e + 2 * k, dts + 2 * j, 2, 1);
|
|
vare_e[k] = vare[j];
|
|
svh_e[k++] = svh[j];
|
|
}
|
|
/* estimate receiver position without a satellite */
|
|
if (!estpos(obs_e, n - 1, rs_e, dts_e, vare_e, svh_e, nav, opt, &sol_e, azel_e,
|
|
vsat_e, resp_e, msg_e))
|
|
{
|
|
trace(3, "raim_fde: exsat=%2d (%s)\n", obs[i].sat, msg);
|
|
continue;
|
|
}
|
|
for (j = nvsat = 0, rms_e = 0.0; j < n - 1; j++)
|
|
{
|
|
if (!vsat_e[j])
|
|
{
|
|
continue;
|
|
}
|
|
rms_e += std::pow(resp_e[j], 2.0);
|
|
nvsat++;
|
|
}
|
|
if (nvsat < 5)
|
|
{
|
|
trace(3, "raim_fde: exsat=%2d lack of satellites nvsat=%2d\n",
|
|
obs[i].sat, nvsat);
|
|
continue;
|
|
}
|
|
rms_e = sqrt(rms_e / nvsat);
|
|
|
|
trace(3, "raim_fde: exsat=%2d rms=%8.3f\n", obs[i].sat, rms_e);
|
|
|
|
if (rms_e > rms)
|
|
{
|
|
continue;
|
|
}
|
|
|
|
/* save result */
|
|
for (j = k = 0; j < n; j++)
|
|
{
|
|
if (j == i)
|
|
{
|
|
continue;
|
|
}
|
|
matcpy(azel + 2 * j, azel_e + 2 * k, 2, 1);
|
|
vsat[j] = vsat_e[k];
|
|
resp[j] = resp_e[k++];
|
|
}
|
|
stat = 1;
|
|
*sol = sol_e;
|
|
sat = obs[i].sat;
|
|
rms = rms_e;
|
|
vsat[i] = 0;
|
|
std::strncpy(msg, msg_e, 128);
|
|
}
|
|
if (stat)
|
|
{
|
|
time2str(obs[0].time, tstr, 2);
|
|
auto name = satno2id(sat);
|
|
trace(2, "%s: %s excluded by raim\n", tstr + 11, name.data());
|
|
}
|
|
free(obs_e);
|
|
free(rs_e);
|
|
free(dts_e);
|
|
free(vare_e);
|
|
free(azel_e);
|
|
free(svh_e);
|
|
free(vsat_e);
|
|
free(resp_e);
|
|
|
|
return stat;
|
|
}
|
|
|
|
|
|
/* doppler residuals ---------------------------------------------------------*/
|
|
int resdop(const obsd_t *obs, int n, const double *rs, const double *dts,
|
|
const nav_t *nav, const double *rr, const double *x,
|
|
const double *azel, const int *vsat, double *v, double *H)
|
|
{
|
|
double lam;
|
|
double rate;
|
|
double pos[3];
|
|
double E[9];
|
|
double a[3];
|
|
double e[3];
|
|
double vs[3];
|
|
double cosel;
|
|
int i;
|
|
int j;
|
|
int nv = 0;
|
|
int band = 0;
|
|
|
|
trace(3, "resdop : n=%d\n", n);
|
|
|
|
ecef2pos(rr, pos);
|
|
xyz2enu(pos, E);
|
|
|
|
for (i = 0; i < n && i < MAXOBS; i++)
|
|
{
|
|
if (obs[i].code[0] != CODE_NONE)
|
|
{
|
|
band = 0;
|
|
}
|
|
if (obs[i].code[1] != CODE_NONE)
|
|
{
|
|
band = 1;
|
|
}
|
|
if (obs[i].code[2] != CODE_NONE)
|
|
{
|
|
band = 2;
|
|
}
|
|
lam = nav->lam[obs[i].sat - 1][band];
|
|
|
|
if (obs[i].D[band] == 0.0 || lam == 0.0 || !vsat[i] || norm_rtk(rs + 3 + i * 6, 3) <= 0.0)
|
|
{
|
|
continue;
|
|
}
|
|
/* line-of-sight vector in ecef */
|
|
cosel = cos(azel[1 + i * 2]);
|
|
a[0] = sin(azel[i * 2]) * cosel;
|
|
a[1] = cos(azel[i * 2]) * cosel;
|
|
a[2] = sin(azel[1 + i * 2]);
|
|
matmul("TN", 3, 1, 3, 1.0, E, a, 0.0, e);
|
|
|
|
/* satellite velocity relative to receiver in ecef */
|
|
for (j = 0; j < 3; j++)
|
|
{
|
|
vs[j] = rs[j + 3 + i * 6] - x[j];
|
|
}
|
|
|
|
/* range rate with earth rotation correction */
|
|
rate = dot(vs, e, 3) + GNSS_OMEGA_EARTH_DOT / SPEED_OF_LIGHT_M_S * (rs[4 + i * 6] * rr[0] + rs[1 + i * 6] * x[0] - rs[3 + i * 6] * rr[1] - rs[i * 6] * x[1]);
|
|
|
|
/* doppler residual */
|
|
v[nv] = -lam * obs[i].D[band] - (rate + x[3] - SPEED_OF_LIGHT_M_S * dts[1 + i * 2]);
|
|
|
|
/* design matrix */
|
|
for (j = 0; j < 4; j++)
|
|
{
|
|
H[j + nv * 4] = j < 3 ? -e[j] : 1.0;
|
|
}
|
|
|
|
nv++;
|
|
}
|
|
return nv;
|
|
}
|
|
|
|
|
|
/* estimate receiver velocity ------------------------------------------------*/
|
|
void estvel(const obsd_t *obs, int n, const double *rs, const double *dts,
|
|
const nav_t *nav, const prcopt_t *opt __attribute__((unused)), sol_t *sol,
|
|
const double *azel, const int *vsat)
|
|
{
|
|
double x[4] = {0};
|
|
double dx[4];
|
|
double Q[16];
|
|
double *v;
|
|
double *H;
|
|
int i;
|
|
int j;
|
|
int nv;
|
|
|
|
trace(3, "estvel : n=%d\n", n);
|
|
|
|
v = mat(n, 1);
|
|
H = mat(4, n);
|
|
|
|
for (i = 0; i < MAXITR; i++)
|
|
{
|
|
/* doppler residuals */
|
|
if ((nv = resdop(obs, n, rs, dts, nav, sol->rr, x, azel, vsat, v, H)) < 4)
|
|
{
|
|
break;
|
|
}
|
|
/* least square estimation */
|
|
if (lsq(H, v, 4, nv, dx, Q))
|
|
{
|
|
break;
|
|
}
|
|
|
|
for (j = 0; j < 4; j++)
|
|
{
|
|
x[j] += dx[j];
|
|
}
|
|
|
|
if (norm_rtk(dx, 4) < 1e-6)
|
|
{
|
|
for (i = 0; i < 3; i++)
|
|
{
|
|
sol->rr[i + 3] = x[i];
|
|
}
|
|
sol->dtr[5] = x[3];
|
|
break;
|
|
}
|
|
}
|
|
free(v);
|
|
free(H);
|
|
}
|
|
|
|
|
|
/* single-point positioning ----------------------------------------------------
|
|
* compute receiver position, velocity, clock bias by single-point positioning
|
|
* with pseudorange and doppler observables
|
|
* args : obsd_t *obs I observation data
|
|
* int n I number of observation data
|
|
* nav_t *nav I navigation data
|
|
* prcopt_t *opt I processing options
|
|
* sol_t *sol IO solution
|
|
* double *azel IO azimuth/elevation angle (rad) (NULL: no output)
|
|
* ssat_t *ssat IO satellite status (NULL: no output)
|
|
* char *msg O error message for error exit
|
|
* return : status(1:ok,0:error)
|
|
* notes : assuming sbas-gps, galileo-gps, qzss-gps, compass-gps time offset and
|
|
* receiver bias are negligible (only involving glonass-gps time offset
|
|
* and receiver bias)
|
|
*-----------------------------------------------------------------------------*/
|
|
int pntpos(const obsd_t *obs, int n, const nav_t *nav,
|
|
const prcopt_t *opt, sol_t *sol, double *azel, ssat_t *ssat,
|
|
char *msg)
|
|
{
|
|
prcopt_t opt_ = *opt;
|
|
double *rs;
|
|
double *dts;
|
|
double *var;
|
|
double *azel_;
|
|
double *resp;
|
|
int i;
|
|
int stat;
|
|
std::vector<int> vsat(MAXOBS, 0);
|
|
std::vector<int> svh(MAXOBS, 0);
|
|
|
|
sol->stat = SOLQ_NONE;
|
|
|
|
if (n <= 0)
|
|
{
|
|
std::strncpy(msg, "no observation data", 20);
|
|
return 0;
|
|
}
|
|
|
|
trace(3, "pntpos : tobs=%s n=%d\n", time_str(obs[0].time, 3), n);
|
|
|
|
sol->time = obs[0].time;
|
|
msg[0] = '\0';
|
|
|
|
rs = mat(6, n);
|
|
dts = mat(2, n);
|
|
var = mat(1, n);
|
|
azel_ = zeros(2, n);
|
|
resp = mat(1, n);
|
|
|
|
if (opt_.mode != PMODE_SINGLE)
|
|
{ /* for precise positioning */
|
|
#if 0
|
|
opt_.sateph = EPHOPT_BRDC;
|
|
#endif
|
|
opt_.ionoopt = IONOOPT_BRDC;
|
|
opt_.tropopt = TROPOPT_SAAS;
|
|
}
|
|
/* satellite positions, velocities and clocks */
|
|
satposs(sol->time, obs, n, nav, opt_.sateph, rs, dts, var, svh.data());
|
|
|
|
/* estimate receiver position with pseudorange */
|
|
stat = estpos(obs, n, rs, dts, var, svh.data(), nav, &opt_, sol, azel_, vsat.data(), resp, msg);
|
|
|
|
/* raim fde */
|
|
if (!stat && n >= 6 && opt->posopt[4])
|
|
{
|
|
stat = raim_fde(obs, n, rs, dts, var, svh.data(), nav, &opt_, sol, azel_, vsat.data(), resp, msg);
|
|
}
|
|
/* estimate receiver velocity with doppler */
|
|
if (stat)
|
|
{
|
|
estvel(obs, n, rs, dts, nav, &opt_, sol, azel_, vsat.data());
|
|
}
|
|
|
|
if (azel)
|
|
{
|
|
for (i = 0; i < n * 2; i++)
|
|
{
|
|
azel[i] = azel_[i];
|
|
}
|
|
}
|
|
if (ssat)
|
|
{
|
|
for (i = 0; i < MAXSAT; i++)
|
|
{
|
|
ssat[i].vs = 0;
|
|
ssat[i].azel[0] = ssat[i].azel[1] = 0.0;
|
|
ssat[i].resp[0] = ssat[i].resc[0] = 0.0;
|
|
ssat[i].snr[0] = 0;
|
|
}
|
|
for (i = 0; i < n; i++)
|
|
{
|
|
ssat[obs[i].sat - 1].azel[0] = azel_[i * 2];
|
|
ssat[obs[i].sat - 1].azel[1] = azel_[1 + i * 2];
|
|
ssat[obs[i].sat - 1].snr[0] = obs[i].SNR[0];
|
|
if (!vsat[i])
|
|
{
|
|
continue;
|
|
}
|
|
ssat[obs[i].sat - 1].vs = 1;
|
|
ssat[obs[i].sat - 1].resp[0] = resp[i];
|
|
}
|
|
}
|
|
free(rs);
|
|
free(dts);
|
|
free(var);
|
|
free(azel_);
|
|
free(resp);
|
|
return stat;
|
|
}
|