| 1 | #include <math.h>
|
|---|
| 2 | #include <sstream>
|
|---|
| 3 | #include <iostream>
|
|---|
| 4 | #include <iomanip>
|
|---|
| 5 | #include <cstring>
|
|---|
| 6 |
|
|---|
| 7 | #include <newmatio.h>
|
|---|
| 8 |
|
|---|
| 9 | #include "ephemeris.h"
|
|---|
| 10 | #include "bncutils.h"
|
|---|
| 11 | #include "timeutils.h"
|
|---|
| 12 | #include "bnctime.h"
|
|---|
| 13 |
|
|---|
| 14 | using namespace std;
|
|---|
| 15 |
|
|---|
| 16 | //
|
|---|
| 17 | ////////////////////////////////////////////////////////////////////////////
|
|---|
| 18 | bool t_eph::isNewerThan(const t_eph* eph) const {
|
|---|
| 19 | if (_GPSweek > eph->_GPSweek ||
|
|---|
| 20 | (_GPSweek == eph->_GPSweek && _GPSweeks > eph->_GPSweeks)) {
|
|---|
| 21 | return true;
|
|---|
| 22 | }
|
|---|
| 23 | else {
|
|---|
| 24 | return false;
|
|---|
| 25 | }
|
|---|
| 26 | }
|
|---|
| 27 |
|
|---|
| 28 | // Set GPS Satellite Position
|
|---|
| 29 | ////////////////////////////////////////////////////////////////////////////
|
|---|
| 30 | void t_ephGPS::set(const gpsephemeris* ee) {
|
|---|
| 31 | ostringstream prn;
|
|---|
| 32 | prn << 'G' << setfill('0') << setw(2) << ee->satellite;
|
|---|
| 33 |
|
|---|
| 34 | _prn = prn.str();
|
|---|
| 35 |
|
|---|
| 36 | // TODO: check if following two lines are correct
|
|---|
| 37 | _GPSweek = ee->GPSweek;
|
|---|
| 38 | _GPSweeks = ee->TOE;
|
|---|
| 39 |
|
|---|
| 40 | _TOW = ee->TOW;
|
|---|
| 41 | _TOC = ee->TOC;
|
|---|
| 42 | _TOE = ee->TOE;
|
|---|
| 43 | _IODE = ee->IODE;
|
|---|
| 44 | _IODC = ee->IODC;
|
|---|
| 45 |
|
|---|
| 46 | _clock_bias = ee->clock_bias ;
|
|---|
| 47 | _clock_drift = ee->clock_drift ;
|
|---|
| 48 | _clock_driftrate = ee->clock_driftrate;
|
|---|
| 49 |
|
|---|
| 50 | _Crs = ee->Crs;
|
|---|
| 51 | _Delta_n = ee->Delta_n;
|
|---|
| 52 | _M0 = ee->M0;
|
|---|
| 53 | _Cuc = ee->Cuc;
|
|---|
| 54 | _e = ee->e;
|
|---|
| 55 | _Cus = ee->Cus;
|
|---|
| 56 | _sqrt_A = ee->sqrt_A;
|
|---|
| 57 | _Cic = ee->Cic;
|
|---|
| 58 | _OMEGA0 = ee->OMEGA0;
|
|---|
| 59 | _Cis = ee->Cis;
|
|---|
| 60 | _i0 = ee->i0;
|
|---|
| 61 | _Crc = ee->Crc;
|
|---|
| 62 | _omega = ee->omega;
|
|---|
| 63 | _OMEGADOT = ee->OMEGADOT;
|
|---|
| 64 | _IDOT = ee->IDOT;
|
|---|
| 65 |
|
|---|
| 66 | _TGD = ee->TGD;
|
|---|
| 67 | }
|
|---|
| 68 |
|
|---|
| 69 | // Compute GPS Satellite Position (virtual)
|
|---|
| 70 | ////////////////////////////////////////////////////////////////////////////
|
|---|
| 71 | void t_ephGPS::position(int GPSweek, double GPSweeks,
|
|---|
| 72 | double* xc,
|
|---|
| 73 | double* vv) const {
|
|---|
| 74 |
|
|---|
| 75 | static const double secPerWeek = 7 * 86400.0;
|
|---|
| 76 | static const double omegaEarth = 7292115.1467e-11;
|
|---|
| 77 | static const double gmWGS = 398.6005e12;
|
|---|
| 78 |
|
|---|
| 79 | memset(xc, 0, 4*sizeof(double));
|
|---|
| 80 | memset(vv, 0, 3*sizeof(double));
|
|---|
| 81 |
|
|---|
| 82 | double a0 = _sqrt_A * _sqrt_A;
|
|---|
| 83 | if (a0 == 0) {
|
|---|
| 84 | return;
|
|---|
| 85 | }
|
|---|
| 86 |
|
|---|
| 87 | double n0 = sqrt(gmWGS/(a0*a0*a0));
|
|---|
| 88 | double tk = GPSweeks - _TOE;
|
|---|
| 89 | if (GPSweek != _GPSweek) {
|
|---|
| 90 | tk += (GPSweek - _GPSweek) * secPerWeek;
|
|---|
| 91 | }
|
|---|
| 92 | double n = n0 + _Delta_n;
|
|---|
| 93 | double M = _M0 + n*tk;
|
|---|
| 94 | double E = M;
|
|---|
| 95 | double E_last;
|
|---|
| 96 | do {
|
|---|
| 97 | E_last = E;
|
|---|
| 98 | E = M + _e*sin(E);
|
|---|
| 99 | } while ( fabs(E-E_last)*a0 > 0.001 );
|
|---|
| 100 | double v = 2.0*atan( sqrt( (1.0 + _e)/(1.0 - _e) )*tan( E/2 ) );
|
|---|
| 101 | double u0 = v + _omega;
|
|---|
| 102 | double sin2u0 = sin(2*u0);
|
|---|
| 103 | double cos2u0 = cos(2*u0);
|
|---|
| 104 | double r = a0*(1 - _e*cos(E)) + _Crc*cos2u0 + _Crs*sin2u0;
|
|---|
| 105 | double i = _i0 + _IDOT*tk + _Cic*cos2u0 + _Cis*sin2u0;
|
|---|
| 106 | double u = u0 + _Cuc*cos2u0 + _Cus*sin2u0;
|
|---|
| 107 | double xp = r*cos(u);
|
|---|
| 108 | double yp = r*sin(u);
|
|---|
| 109 | double OM = _OMEGA0 + (_OMEGADOT - omegaEarth)*tk -
|
|---|
| 110 | omegaEarth*_TOE;
|
|---|
| 111 |
|
|---|
| 112 | double sinom = sin(OM);
|
|---|
| 113 | double cosom = cos(OM);
|
|---|
| 114 | double sini = sin(i);
|
|---|
| 115 | double cosi = cos(i);
|
|---|
| 116 | xc[0] = xp*cosom - yp*cosi*sinom;
|
|---|
| 117 | xc[1] = xp*sinom + yp*cosi*cosom;
|
|---|
| 118 | xc[2] = yp*sini;
|
|---|
| 119 |
|
|---|
| 120 | double tc = GPSweeks - _TOC;
|
|---|
| 121 | if (GPSweek != _GPSweek) {
|
|---|
| 122 | tc += (GPSweek - _GPSweek) * secPerWeek;
|
|---|
| 123 | }
|
|---|
| 124 | xc[3] = _clock_bias + _clock_drift*tc + _clock_driftrate*tc*tc
|
|---|
| 125 | - 4.442807633e-10 * _e * sqrt(a0) *sin(E);
|
|---|
| 126 |
|
|---|
| 127 | // Velocity
|
|---|
| 128 | // --------
|
|---|
| 129 | double tanv2 = tan(v/2);
|
|---|
| 130 | double dEdM = 1 / (1 - _e*cos(E));
|
|---|
| 131 | double dotv = sqrt((1.0 + _e)/(1.0 - _e)) / cos(E/2)/cos(E/2) / (1 + tanv2*tanv2)
|
|---|
| 132 | * dEdM * n;
|
|---|
| 133 | double dotu = dotv + (-_Cuc*sin2u0 + _Cus*cos2u0)*2*dotv;
|
|---|
| 134 | double dotom = _OMEGADOT - omegaEarth;
|
|---|
| 135 | double doti = _IDOT + (-_Cic*sin2u0 + _Cis*cos2u0)*2*dotv;
|
|---|
| 136 | double dotr = a0 * _e*sin(E) * dEdM * n
|
|---|
| 137 | + (-_Crc*sin2u0 + _Crs*cos2u0)*2*dotv;
|
|---|
| 138 | double dotx = dotr*cos(u) - r*sin(u)*dotu;
|
|---|
| 139 | double doty = dotr*sin(u) + r*cos(u)*dotu;
|
|---|
| 140 |
|
|---|
| 141 | vv[0] = cosom *dotx - cosi*sinom *doty // dX / dr
|
|---|
| 142 | - xp*sinom*dotom - yp*cosi*cosom*dotom // dX / dOMEGA
|
|---|
| 143 | + yp*sini*sinom*doti; // dX / di
|
|---|
| 144 |
|
|---|
| 145 | vv[1] = sinom *dotx + cosi*cosom *doty
|
|---|
| 146 | + xp*cosom*dotom - yp*cosi*sinom*dotom
|
|---|
| 147 | - yp*sini*cosom*doti;
|
|---|
| 148 |
|
|---|
| 149 | vv[2] = sini *doty + yp*cosi *doti;
|
|---|
| 150 | }
|
|---|
| 151 |
|
|---|
| 152 |
|
|---|
| 153 | // Derivative of the state vector using a simple force model (static)
|
|---|
| 154 | ////////////////////////////////////////////////////////////////////////////
|
|---|
| 155 | ColumnVector t_ephGlo::glo_deriv(double /* tt */, const ColumnVector& xv) {
|
|---|
| 156 |
|
|---|
| 157 | // State vector components
|
|---|
| 158 | // -----------------------
|
|---|
| 159 | ColumnVector rr = xv.rows(1,3);
|
|---|
| 160 | ColumnVector vv = xv.rows(4,6);
|
|---|
| 161 |
|
|---|
| 162 | // Acceleration
|
|---|
| 163 | // ------------
|
|---|
| 164 | static const double GM = 398.60044e12;
|
|---|
| 165 | static const double AE = 6378136.0;
|
|---|
| 166 | static const double OMEGA = 7292115.e-11;
|
|---|
| 167 | static const double C20 = -1082.63e-6;
|
|---|
| 168 |
|
|---|
| 169 | double rho = rr.norm_Frobenius();
|
|---|
| 170 | double t1 = -GM/(rho*rho*rho);
|
|---|
| 171 | double t2 = 3.0/2.0 * C20 * (GM*AE*AE) / (rho*rho*rho*rho*rho);
|
|---|
| 172 | double t3 = OMEGA * OMEGA;
|
|---|
| 173 | double t4 = 2.0 * OMEGA;
|
|---|
| 174 | double z2 = rr(3) * rr(3);
|
|---|
| 175 |
|
|---|
| 176 | // Vector of derivatives
|
|---|
| 177 | // ---------------------
|
|---|
| 178 | ColumnVector va(6);
|
|---|
| 179 | va(1) = vv(1);
|
|---|
| 180 | va(2) = vv(2);
|
|---|
| 181 | va(3) = vv(3);
|
|---|
| 182 | va(4) = (t1 + t2*(1.0-5.0*z2/(rho*rho)) + t3) * rr(1) + t4*vv(2);
|
|---|
| 183 | va(5) = (t1 + t2*(1.0-5.0*z2/(rho*rho)) + t3) * rr(2) - t4*vv(1);
|
|---|
| 184 | va(6) = (t1 + t2*(3.0-5.0*z2/(rho*rho)) ) * rr(3);
|
|---|
| 185 |
|
|---|
| 186 | return va;
|
|---|
| 187 | }
|
|---|
| 188 |
|
|---|
| 189 | // Compute Glonass Satellite Position (virtual)
|
|---|
| 190 | ////////////////////////////////////////////////////////////////////////////
|
|---|
| 191 | void t_ephGlo::position(int GPSweek, double GPSweeks,
|
|---|
| 192 | double* xc, double* vv) const {
|
|---|
| 193 |
|
|---|
| 194 | static const double secPerWeek = 7 * 86400.0;
|
|---|
| 195 | static const double nominalStep = 10.0;
|
|---|
| 196 |
|
|---|
| 197 | memset(xc, 0, 4*sizeof(double));
|
|---|
| 198 | memset(vv, 0, 3*sizeof(double));
|
|---|
| 199 |
|
|---|
| 200 | double dtPos = GPSweeks - _tt;
|
|---|
| 201 | if (GPSweek != _GPSweek) {
|
|---|
| 202 | dtPos += (GPSweek - _GPSweek) * secPerWeek;
|
|---|
| 203 | }
|
|---|
| 204 |
|
|---|
| 205 | int nSteps = int(fabs(dtPos) / nominalStep) + 1;
|
|---|
| 206 | double step = dtPos / nSteps;
|
|---|
| 207 |
|
|---|
| 208 | for (int ii = 1; ii <= nSteps; ii++) {
|
|---|
| 209 | _xv = rungeKutta4(_tt, _xv, step, glo_deriv);
|
|---|
| 210 | _tt += step;
|
|---|
| 211 | }
|
|---|
| 212 |
|
|---|
| 213 | // Position and Velocity
|
|---|
| 214 | // ---------------------
|
|---|
| 215 | xc[0] = _xv(1);
|
|---|
| 216 | xc[1] = _xv(2);
|
|---|
| 217 | xc[2] = _xv(3);
|
|---|
| 218 |
|
|---|
| 219 | vv[0] = _xv(4);
|
|---|
| 220 | vv[1] = _xv(5);
|
|---|
| 221 | vv[2] = _xv(6);
|
|---|
| 222 |
|
|---|
| 223 | // Clock Correction
|
|---|
| 224 | // ----------------
|
|---|
| 225 | double dtClk = GPSweeks - _GPSweeks;
|
|---|
| 226 | if (GPSweek != _GPSweek) {
|
|---|
| 227 | dtClk += (GPSweek - _GPSweek) * secPerWeek;
|
|---|
| 228 | }
|
|---|
| 229 | xc[3] = -_tau + _gamma * dtClk;
|
|---|
| 230 | }
|
|---|
| 231 |
|
|---|
| 232 | // IOD of Glonass Ephemeris (virtual)
|
|---|
| 233 | ////////////////////////////////////////////////////////////////////////////
|
|---|
| 234 | int t_ephGlo::IOD() const {
|
|---|
| 235 |
|
|---|
| 236 | bool old = false;
|
|---|
| 237 |
|
|---|
| 238 | if (old) { // 5 LSBs of iod are equal to 5 LSBs of tb
|
|---|
| 239 | unsigned int tb = int(fmod(_GPSweeks,86400.0)); //sec of day
|
|---|
| 240 | const int shift = sizeof(tb) * 8 - 5;
|
|---|
| 241 | unsigned int iod = tb << shift;
|
|---|
| 242 | return (iod >> shift);
|
|---|
| 243 | }
|
|---|
| 244 | else {
|
|---|
| 245 | bncTime tGPS(_GPSweek, _GPSweeks);
|
|---|
| 246 | int hlpWeek = _GPSweek;
|
|---|
| 247 | int hlpSec = int(_GPSweeks);
|
|---|
| 248 | int hlpMsec = int(_GPSweeks * 1000);
|
|---|
| 249 | updatetime(&hlpWeek, &hlpSec, hlpMsec, 0);
|
|---|
| 250 | bncTime tHlp(hlpWeek, hlpSec);
|
|---|
| 251 | double diffSec = tGPS - tHlp;
|
|---|
| 252 | bncTime tMoscow = tGPS + diffSec;
|
|---|
| 253 | return int(tMoscow.daysec() / 900);
|
|---|
| 254 | }
|
|---|
| 255 | }
|
|---|
| 256 |
|
|---|
| 257 | // Set Glonass Ephemeris
|
|---|
| 258 | ////////////////////////////////////////////////////////////////////////////
|
|---|
| 259 | void t_ephGlo::set(const glonassephemeris* ee) {
|
|---|
| 260 |
|
|---|
| 261 | ostringstream prn;
|
|---|
| 262 | prn << 'R' << setfill('0') << setw(2) << ee->almanac_number;
|
|---|
| 263 | _prn = prn.str();
|
|---|
| 264 |
|
|---|
| 265 | int ww = ee->GPSWeek;
|
|---|
| 266 | int tow = ee->GPSTOW;
|
|---|
| 267 | updatetime(&ww, &tow, ee->tb*1000, 0); // Moscow -> GPS
|
|---|
| 268 |
|
|---|
| 269 | _GPSweek = ww;
|
|---|
| 270 | _GPSweeks = tow;
|
|---|
| 271 | _E = ee->E;
|
|---|
| 272 | _tau = ee->tau;
|
|---|
| 273 | _gamma = ee->gamma;
|
|---|
| 274 | _x_pos = ee->x_pos;
|
|---|
| 275 | _x_velocity = ee->x_velocity;
|
|---|
| 276 | _x_acceleration = ee->x_acceleration;
|
|---|
| 277 | _y_pos = ee->y_pos;
|
|---|
| 278 | _y_velocity = ee->y_velocity;
|
|---|
| 279 | _y_acceleration = ee->y_acceleration;
|
|---|
| 280 | _z_pos = ee->z_pos;
|
|---|
| 281 | _z_velocity = ee->z_velocity;
|
|---|
| 282 | _z_acceleration = ee->z_acceleration;
|
|---|
| 283 | _health = 0;
|
|---|
| 284 | _frequency_number = ee->frequency_number;
|
|---|
| 285 | _tki = ee->tk-3*60*60; if (_tki < 0) _tki += 86400;
|
|---|
| 286 |
|
|---|
| 287 | // Initialize status vector
|
|---|
| 288 | // ------------------------
|
|---|
| 289 | _tt = _GPSweeks;
|
|---|
| 290 |
|
|---|
| 291 | _xv(1) = _x_pos * 1.e3;
|
|---|
| 292 | _xv(2) = _y_pos * 1.e3;
|
|---|
| 293 | _xv(3) = _z_pos * 1.e3;
|
|---|
| 294 | _xv(4) = _x_velocity * 1.e3;
|
|---|
| 295 | _xv(5) = _y_velocity * 1.e3;
|
|---|
| 296 | _xv(6) = _z_velocity * 1.e3;
|
|---|
| 297 | }
|
|---|
