/* temporal update of tropospheric parameters --------------------------------*/
static void udtrop_ppp(rtk_t *rtk)
{
double pos[3],azel[]={0.0,PI/2.0},ztd,var;
int i=IT(&rtk->opt),j;
trace(3,"udtrop_ppp:\n");
if (rtk->x[i]==0.0) {
ecef2pos(rtk->sol.rr,pos);
ztd=sbstropcorr(rtk->sol.time,pos,azel,&var);
initx(rtk,ztd,var,i);
if (rtk->opt.tropopt>=TROPOPT_ESTG) {
for (j=0;j<2;j++) initx(rtk,1E-6,VAR_GRA,++i);
}
}
else {
rtk->P[i*(1+rtk->nx)]+=SQR(rtk->opt.prn[2])*fabs(rtk->tt);
if (rtk->opt.tropopt>=TROPOPT_ESTG) {
for (j=0;j<2;j++) {
rtk->P[++i*(1+rtk->nx)]+=SQR(rtk->opt.prn[2]*0.1)*fabs(rtk->tt);
}
}
}
}
/* tropospheric correction -----------------------------------------------------
* compute tropospheric correction
* args : gtime_t time I time
* nav_t *nav I navigation data
* double *pos I receiver position {lat,lon,h} (rad|m)
* double *azel I azimuth/elevation angle {az,el} (rad)
* int tropopt I tropospheric correction option (TROPOPT_???)
* double *trp O tropospheric delay (m)
* double *var O tropospheric delay variance (m^2)
* return : status(1:ok,0:error)
*-----------------------------------------------------------------------------*/
extern int tropcorr(gtime_t time, const nav_t *nav, const double *pos,
const double *azel, int tropopt, double *trp, double *var)
{
/* saastamoinen model */
if (tropopt == TROPOPT_SAAS || tropopt == TROPOPT_EST || tropopt == TROPOPT_ESTG) {
*trp = tropmodel(time, pos, azel, REL_HUMI);
*var = SQR(ERR_SAAS / (sin(azel[1]) + 0.1));
return 1;
}
/* sbas troposphere model */
if (tropopt == TROPOPT_SBAS) {
*trp = sbstropcorr(time, pos, azel, var);
return 1;
}
/* no correction */
*trp = 0.0;
*var = tropopt == TROPOPT_OFF ? SQR(ERR_TROP) : 0.0;
return 1;
}
/* tropospheric correction -----------------------------------------------------
* compute tropospheric correction
* args : gtime_t time I time
* nav_t *nav I navigation data
* double *pos I receiver position {lat,lon,h} (rad|m)
* double *azel I azimuth/elevation angle {az,el} (rad)
* int tropopt I tropospheric correction option (TROPOPT_???)
* double *trp O tropospheric delay (m)
* double *var O tropospheric delay variance (m^2)
* return : status(1:ok,0:error)
*-----------------------------------------------------------------------------*/
extern int tropcorr(gtime_t time, const nav_t *nav, const double *pos,
const double *azel, int tropopt, double *trp, double *var)
{
trace(4,"tropcorr: time=%s opt=%d pos=%.3f %.3f azel=%.3f %.3f\n",
time_str(time,3),tropopt,pos[0]*R2D,pos[1]*R2D,azel[0]*R2D,
azel[1]*R2D);
/* saastamoinen model */
if (tropopt==TROPOPT_SAAS||tropopt==TROPOPT_EST||tropopt==TROPOPT_ESTG) {
*trp=tropmodel(time,pos,azel,REL_HUMI);
*var=SQR(ERR_SAAS/(sin(azel[1])+0.1));
return 1;
}
/* sbas troposphere model */
if (tropopt==TROPOPT_SBAS) {
*trp=sbstropcorr(time,pos,azel,var);
return 1;
}
/* no correction */
*trp=0.0;
*var=tropopt==TROPOPT_OFF?SQR(ERR_TROP):0.0;
return 1;
}
/* phase and code residuals --------------------------------------------------*/
static int res_ppp(int iter, const obsd_t *obs, int n, const double *rs,
const double *dts, const double *vare, const int *svh,
const nav_t *nav, const double *x, rtk_t *rtk, double *v,
double *H, double *R, double *azel)
{
prcopt_t *opt=&rtk->opt;
double r,rr[3],disp[3],pos[3],e[3],meas[2],dtdx[3],dantr[NFREQ]={0};
double dants[NFREQ]={0},var[MAXOBS*2],dtrp=0.0,vart=0.0,varm[2]={0};
int i,j,k,sat,sys,nv=0,nx=rtk->nx,brk,tideopt;
trace(3,"res_ppp : n=%d nx=%d\n",n,nx);
for (i=0;i<MAXSAT;i++) rtk->ssat[i].vsat[0]=0;
for (i=0;i<3;i++) rr[i]=x[i];
/* earth tides correction */
if (opt->tidecorr) {
tideopt=opt->tidecorr==1?1:7; /* 1:solid, 2:solid+otl+pole */
tidedisp(gpst2utc(obs[0].time),rr,tideopt,&nav->erp,opt->odisp[0],
disp);
for (i=0;i<3;i++) rr[i]+=disp[i];
}
ecef2pos(rr,pos);
for (i=0;i<n&&i<MAXOBS;i++) {
sat=obs[i].sat;
if (!(sys=satsys(sat,NULL))||!rtk->ssat[sat-1].vs) continue;
/* geometric distance/azimuth/elevation angle */
if ((r=geodist(rs+i*6,rr,e))<=0.0||
satazel(pos,e,azel+i*2)<opt->elmin) continue;
/* excluded satellite? */
if (satexclude(obs[i].sat,svh[i],opt)) continue;
/* tropospheric delay correction */
if (opt->tropopt==TROPOPT_SAAS) {
dtrp=tropmodel(obs[i].time,pos,azel+i*2,REL_HUMI);
vart=SQR(ERR_SAAS);
}
else if (opt->tropopt==TROPOPT_SBAS) {
dtrp=sbstropcorr(obs[i].time,pos,azel+i*2,&vart);
}
else if (opt->tropopt==TROPOPT_EST||opt->tropopt==TROPOPT_ESTG) {
dtrp=prectrop(obs[i].time,pos,azel+i*2,opt,x+IT(opt),dtdx,&vart);
}
else if (opt->tropopt==TROPOPT_COR||opt->tropopt==TROPOPT_CORG) {
dtrp=prectrop(obs[i].time,pos,azel+i*2,opt,x,dtdx,&vart);
}
/* satellite antenna model */
if (opt->posopt[0]) {
satantpcv(rs+i*6,rr,nav->pcvs+sat-1,dants);
}
/* receiver antenna model */
antmodel(opt->pcvr,opt->antdel[0],azel+i*2,opt->posopt[1],dantr);
/* phase windup correction */
if (opt->posopt[2]) {
windupcorr(rtk->sol.time,rs+i*6,rr,&rtk->ssat[sat-1].phw);
}
/* ionosphere and antenna phase corrected measurements */
if (!corrmeas(obs+i,nav,pos,azel+i*2,&rtk->opt,dantr,dants,
rtk->ssat[sat-1].phw,meas,varm,&brk)) {
continue;
}
/* satellite clock and tropospheric delay */
r+=-CLIGHT*dts[i*2]+dtrp;
trace(5,"sat=%2d azel=%6.1f %5.1f dtrp=%.3f dantr=%6.3f %6.3f dants=%6.3f %6.3f phw=%6.3f\n",
sat,azel[i*2]*R2D,azel[1+i*2]*R2D,dtrp,dantr[0],dantr[1],dants[0],
dants[1],rtk->ssat[sat-1].phw);
for (j=0;j<2;j++) { /* for phase and code */
if (meas[j]==0.0) continue;
for (k=0;k<nx;k++) H[k+nx*nv]=0.0;
v[nv]=meas[j]-r;
for (k=0;k<3;k++) H[k+nx*nv]=-e[k];
if (sys!=SYS_GLO) {
v[nv]-=x[IC(0,opt)];
H[IC(0,opt)+nx*nv]=1.0;
}
else {
v[nv]-=x[IC(1,opt)];
H[IC(1,opt)+nx*nv]=1.0;
}
if (opt->tropopt>=TROPOPT_EST) {
for (k=0;k<(opt->tropopt>=TROPOPT_ESTG?3:1);k++) {
H[IT(opt)+k+nx*nv]=dtdx[k];
}
}
if (j==0) {
v[nv]-=x[IB(obs[i].sat,opt)];
H[IB(obs[i].sat,opt)+nx*nv]=1.0;
}
var[nv]=varerr(obs[i].sat,sys,azel[1+i*2],j,opt)+varm[j]+vare[i]+vart;
if (j==0) rtk->ssat[sat-1].resc[0]=v[nv];
else rtk->ssat[sat-1].resp[0]=v[nv];
/* test innovation */
#if 0
if (opt->maxinno>0.0&&fabs(v[nv])>opt->maxinno) {
#else
if (opt->maxinno>0.0&&fabs(v[nv])>opt->maxinno&&sys!=SYS_GLO) {
#endif
trace(2,"ppp outlier rejected %s sat=%2d type=%d v=%.3f\n",
time_str(obs[i].time,0),sat,j,v[nv]);
rtk->ssat[sat-1].rejc[0]++;
continue;
}
if (j==0) rtk->ssat[sat-1].vsat[0]=1;
nv++;
}
}
for (i=0;i<nv;i++) for (j=0;j<nv;j++) {
R[i+j*nv]=i==j?var[i]:0.0;
}
trace(5,"x=\n"); tracemat(5,x, 1,nx,8,3);
trace(5,"v=\n"); tracemat(5,v, 1,nv,8,3);
trace(5,"H=\n"); tracemat(5,H,nx,nv,8,3);
trace(5,"R=\n"); tracemat(5,R,nv,nv,8,5);
return nv;
}
/* number of estimated states ------------------------------------------------*/
extern int pppnx(const prcopt_t *opt)
{
return NX(opt);
}
/* precise point positioning -------------------------------------------------*/
extern void pppos(rtk_t *rtk, const obsd_t *obs, int n, const nav_t *nav)
{
const prcopt_t *opt=&rtk->opt;
double *rs,*dts,*var,*v,*H,*R,*azel,*xp,*Pp;
int i,nv,info,svh[MAXOBS],stat=SOLQ_SINGLE;
trace(3,"pppos : nx=%d n=%d\n",rtk->nx,n);
rs=mat(6,n); dts=mat(2,n); var=mat(1,n); azel=zeros(2,n);
for (i=0;i<MAXSAT;i++) rtk->ssat[i].fix[0]=0;
/* temporal update of states */
udstate_ppp(rtk,obs,n,nav);
trace(4,"x(0)="); tracemat(4,rtk->x,1,NR(opt),13,4);
/* satellite positions and clocks */
satposs(obs[0].time,obs,n,nav,rtk->opt.sateph,rs,dts,var,svh);
/* exclude measurements of eclipsing satellite */
if (rtk->opt.posopt[3]) {
testeclipse(obs,n,nav,rs);
}
xp=mat(rtk->nx,1); Pp=zeros(rtk->nx,rtk->nx);
matcpy(xp,rtk->x,rtk->nx,1);
nv=n*rtk->opt.nf*2; v=mat(nv,1); H=mat(rtk->nx,nv); R=mat(nv,nv);
for (i=0;i<rtk->opt.niter;i++) {
/* phase and code residuals */
if ((nv=res_ppp(i,obs,n,rs,dts,var,svh,nav,xp,rtk,v,H,R,azel))<=0) break;
/* measurement update */
matcpy(Pp,rtk->P,rtk->nx,rtk->nx);
if ((info=filter(xp,Pp,H,v,R,rtk->nx,nv))) {
trace(2,"ppp filter error %s info=%d\n",time_str(rtk->sol.time,0),
info);
break;
}
trace(4,"x(%d)=",i+1); tracemat(4,xp,1,NR(opt),13,4);
stat=SOLQ_PPP;
}
if (stat==SOLQ_PPP) {
/* postfit residuals */
res_ppp(1,obs,n,rs,dts,var,svh,nav,xp,rtk,v,H,R,azel);
/* update state and covariance matrix */
matcpy(rtk->x,xp,rtk->nx,1);
matcpy(rtk->P,Pp,rtk->nx,rtk->nx);
/* ambiguity resolution in ppp */
if (opt->modear==ARMODE_PPPAR||opt->modear==ARMODE_PPPAR_ILS) {
if (pppamb(rtk,obs,n,nav,azel)) stat=SOLQ_FIX;
}
/* update solution status */
rtk->sol.ns=0;
for (i=0;i<n&&i<MAXOBS;i++) {
if (!rtk->ssat[obs[i].sat-1].vsat[0]) continue;
rtk->ssat[obs[i].sat-1].lock[0]++;
rtk->ssat[obs[i].sat-1].outc[0]=0;
rtk->ssat[obs[i].sat-1].fix [0]=4;
rtk->sol.ns++;
}
rtk->sol.stat=stat;
for (i=0;i<3;i++) {
rtk->sol.rr[i]=rtk->x[i];
rtk->sol.qr[i]=(float)rtk->P[i+i*rtk->nx];
}
rtk->sol.qr[3]=(float)rtk->P[1];
rtk->sol.qr[4]=(float)rtk->P[2+rtk->nx];
rtk->sol.qr[5]=(float)rtk->P[2];
rtk->sol.dtr[0]=rtk->x[IC(0,opt)];
rtk->sol.dtr[1]=rtk->x[IC(1,opt)]-rtk->x[IC(0,opt)];
for (i=0;i<n&&i<MAXOBS;i++) {
rtk->ssat[obs[i].sat-1].snr[0]=MIN(obs[i].SNR[0],obs[i].SNR[1]);
}
for (i=0;i<MAXSAT;i++) {
if (rtk->ssat[i].slip[0]&3) rtk->ssat[i].slipc[0]++;
}
}
free(rs); free(dts); free(var); free(azel);
free(xp); free(Pp); free(v); free(H); free(R);
}
