diff --git a/app/consapp/rtkrcv/rtkrcv.c b/app/consapp/rtkrcv/rtkrcv.c
index e909f5107..2f9f06d5e 100644
--- a/app/consapp/rtkrcv/rtkrcv.c
+++ b/app/consapp/rtkrcv/rtkrcv.c
@@ -868,7 +868,7 @@ static void probserv(vt_t *vt, int nf)
         for (j=0;j<nf;j++) vt_printf(vt,"%13.3f",obs[i].P[j]);
         for (j=0;j<nf;j++) vt_printf(vt,"%14.3f",obs[i].L[j]);
         for (j=0;j<nf;j++) vt_printf(vt,"%8.1f" ,obs[i].D[j]);
-        for (j=0;j<nf;j++) vt_printf(vt,"%3.0f" ,obs[i].SNR[j]*SNR_UNIT);
+        for (j=0;j<nf;j++) vt_printf(vt,"%3.0f" ,obs[i].SNR[j]);
         for (j=0;j<nf;j++) vt_printf(vt,"%2d"   ,obs[i].LLI[j]);
         vt_printf(vt,"\n");
     }
diff --git a/app/qtapp/rtknavi_qt/mondlg.cpp b/app/qtapp/rtknavi_qt/mondlg.cpp
index b032d522b..606173100 100644
--- a/app/qtapp/rtknavi_qt/mondlg.cpp
+++ b/app/qtapp/rtknavi_qt/mondlg.cpp
@@ -1066,7 +1066,7 @@ void MonitorDialog::showObservations()
             else ui->tWConsole->item(i, j++)->setText("-");
         }
         for (k = 0; k < NFREQ + nex; k++) {
-            if (obs[i].SNR[k]) ui->tWConsole->item(i, j++)->setText(QString::number(obs[i].SNR[k] * SNR_UNIT, 'f', 1));
+            if (obs[i].SNR[k]) ui->tWConsole->item(i, j++)->setText(QString::number(obs[i].SNR[k], 'f', 1));
             else ui->tWConsole->item(i, j++)->setText("-");
         }
         for (k = 0; k < NFREQ + nex; k++)
diff --git a/app/qtapp/rtkplot_qt/plotcmn.cpp b/app/qtapp/rtkplot_qt/plotcmn.cpp
index f47403e9c..0841320cd 100644
--- a/app/qtapp/rtkplot_qt/plotcmn.cpp
+++ b/app/qtapp/rtkplot_qt/plotcmn.cpp
@@ -342,7 +342,7 @@ QColor Plot::observationColor(const obsd_t *obs, double az, double el, QVariant
         if (obs->L[freq-1] == 0.0 && obs->P[freq-1] == 0.0) {
             return Qt::black;
         }
-        color = snrColor(obs->SNR[freq-1] * SNR_UNIT);
+        color = snrColor(obs->SNR[freq-1]);
     } else {  // code
         for (i = 0; i < NFREQ + NEXOBS; i++) {
             if (!strcmp(code2obs(obs->code[i]), qPrintable(obstype.toString()))) break;
@@ -353,7 +353,7 @@ QColor Plot::observationColor(const obsd_t *obs, double az, double el, QVariant
         if (obs->L[i] == 0.0 && obs->P[i] == 0.0) {
             return Qt::black;
         }
-        color = snrColor(obs->SNR[i] * SNR_UNIT);
+        color = snrColor(obs->SNR[i]);
     }
 
     // check against elevation mask
diff --git a/app/qtapp/rtkplot_qt/plotdata.cpp b/app/qtapp/rtkplot_qt/plotdata.cpp
index 38f1cffe3..64dd54579 100644
--- a/app/qtapp/rtkplot_qt/plotdata.cpp
+++ b/app/qtapp/rtkplot_qt/plotdata.cpp
@@ -1032,7 +1032,7 @@ void Plot::saveSnrMp(const QString &file)
                 time2str(timeadd(gpst2utc(time), 9 * 3600.0), tstr, 1);
             }
             data = QString("%1 %2 %3 %4 %5 %6f\n").arg(tstr).arg(sat, 6).arg(azimuth[j] * R2D, 8, 'f', 1)
-                       .arg(elevation[j] * R2D, 8, 'f', 1).arg(observation.data[j].SNR[k] * SNR_UNIT, 9, 'f', 2).arg(!multipath[k] ? 0.0 : multipath[k][j], 10, 'f', 4);
+                       .arg(elevation[j] * R2D, 8, 'f', 1).arg(observation.data[j].SNR[k], 9, 'f', 2).arg(!multipath[k] ? 0.0 : multipath[k][j], 10, 'f', 4);
             fp.write(data.toLatin1());
         }
     }
diff --git a/app/qtapp/rtkplot_qt/plotdraw.cpp b/app/qtapp/rtkplot_qt/plotdraw.cpp
index 5ceae5bb1..17b0f00f7 100644
--- a/app/qtapp/rtkplot_qt/plotdraw.cpp
+++ b/app/qtapp/rtkplot_qt/plotdraw.cpp
@@ -1509,7 +1509,7 @@ void Plot::drawSky(QPainter &c, int level)
                     if (obs->P[j] == 0.0 && obs->L[j] == 0.0)
                         s += "-- ";
                     else
-                        s += QStringLiteral("%1 ").arg(obs->SNR[j] * SNR_UNIT, 2, 'f', 0, QChar('0'));
+                        s += QStringLiteral("%1 ").arg(obs->SNR[j], 2, 'f', 0, QChar('0'));
                 }
 
                 // LLI
@@ -1532,7 +1532,7 @@ void Plot::drawSky(QPainter &c, int level)
                 if (obs->P[freq - 1] == 0.0 && obs->L[freq - 1] == 0.0)
                     s += "---- ";
                 else
-                    s += QStringLiteral("%1 ").arg(obs->SNR[freq - 1] * SNR_UNIT, 4, 'f', 1);
+                    s += QStringLiteral("%1 ").arg(obs->SNR[freq - 1], 4, 'f', 1);
 
                 // LLI
                 if (obs->L[freq-1] == 0.0)
@@ -1554,7 +1554,7 @@ void Plot::drawSky(QPainter &c, int level)
                 if (obs->P[j] == 0.0 && obs->L[j] == 0.0)
                     s += "---- ";
                 else
-                    s += QStringLiteral("%1 ").arg(obs->SNR[j] * SNR_UNIT, 4, 'f', 1);
+                    s += QStringLiteral("%1 ").arg(obs->SNR[j], 4, 'f', 1);
 
                 // LLI
                 if (obs->L[j] == 0.0)
@@ -1861,12 +1861,12 @@ void Plot::drawSnr(QPainter &c, int level)
                         }
                         if (idx >= NFREQ + NEXOBS) continue;
                     }
-                    if (obs->SNR[idx] * SNR_UNIT <= 0.0) continue;  // skip negative SNR
+                    if (obs->SNR[idx] <= 0.0) continue;  // skip negative SNR
 
                     // calculate position
                     x[n] = timePosition(obs->time);
                     if (panel == 0) {  // SNR
-                        y[n] = obs->SNR[idx] * SNR_UNIT;
+                        y[n] = obs->SNR[idx];
                         col[n] = plotOptDialog->getMarkerColor(0, 4);
                     } else if (panel == 1) {  // multipath
                         if (!multipath[idx] || multipath[idx][j] == 0.0) continue;
@@ -1878,7 +1878,7 @@ void Plot::drawSnr(QPainter &c, int level)
                         if (simulatedObservation)
                             col[n] = sysColor(obs->sat);
                         else
-                            col[n] = snrColor(obs->SNR[idx] * SNR_UNIT);
+                            col[n] = snrColor(obs->SNR[idx]);
 
                         if (elevation[j] > 0.0 && elevation[j] < plotOptDialog->getElevationMask() * D2R) col[n] = plotOptDialog->getMarkerColor(0, 0);
                     }
@@ -2059,10 +2059,10 @@ void Plot::drawSnrE(QPainter &c, int level)
                     }
                     if (idx >= NFREQ + NEXOBS) continue;
                 }
-                if (obs->SNR[idx] * SNR_UNIT <= 0.0) continue;
+                if (obs->SNR[idx] <= 0.0) continue;
 
                 x[0][n[0]] = x[1][n[1]] = elevation[j] * R2D;
-                y[0][n[0]] = obs->SNR[idx] * SNR_UNIT;
+                y[0][n[0]] = obs->SNR[idx];
                 y[1][n[1]] = !multipath[idx] ? 0.0 : multipath[idx][j];
 
                 col[0][n[0]] = col[1][n[1]] = (elevation[j] > 0.0 && elevation[j] < plotOptDialog->getElevationMask() * D2R) ?\
@@ -2340,7 +2340,7 @@ void Plot::drawResidual(QPainter &c, int level)
                 y[0][m[0]] = solstat->resp;
                 y[1][m[1]] = solstat->resc;
                 y[2][m[2]] = solstat->el * R2D;
-                y[3][m[3]] = solstat->snr * SNR_UNIT;
+                y[3][m[3]] = solstat->snr;
 
                 if (!(solstat->flag >> 5)) q = 0;          // invalid
                 else if ((solstat->flag & 7) <= 1) q = 2;  // float
diff --git a/app/winapp/rtknavi/mondlg.cpp b/app/winapp/rtknavi/mondlg.cpp
index 1c10530b2..141180eb2 100644
--- a/app/winapp/rtknavi/mondlg.cpp
+++ b/app/winapp/rtknavi/mondlg.cpp
@@ -1004,7 +1004,7 @@ void __fastcall TMonitorDialog::ShowObs(void)
 			else       Tbl->Cells[j++][i+1]="-";
 		}
 		for (k=0;k<NFREQ+nex;k++) {
-			if (obs[i].SNR[k]) Tbl->Cells[j++][i+1]=s.sprintf("%.1f",obs[i].SNR[k]*SNR_UNIT);
+			if (obs[i].SNR[k]) Tbl->Cells[j++][i+1]=s.sprintf("%.1f",obs[i].SNR[k]);
 			else               Tbl->Cells[j++][i+1]=s.sprintf("-");
 		}
 		for (k=0;k<NFREQ+nex;k++) {
diff --git a/app/winapp/rtkplot/plotcmn.cpp b/app/winapp/rtkplot/plotcmn.cpp
index 58274092f..7c3885d6f 100644
--- a/app/winapp/rtkplot/plotcmn.cpp
+++ b/app/winapp/rtkplot/plotcmn.cpp
@@ -342,7 +342,7 @@ TColor __fastcall TPlot::ObsColor(const obsd_t *obs, double az, double el)
         if (obs->L[freq-1]==0.0&&obs->P[freq-1]==0.0) {
             return clBlack;
         }
-        color=SnrColor(obs->SNR[freq-1]*SNR_UNIT);
+        color=SnrColor(obs->SNR[freq-1]);
     }
     else {
         for (i=0;i<NFREQ+NEXOBS;i++) {
@@ -354,7 +354,7 @@ TColor __fastcall TPlot::ObsColor(const obsd_t *obs, double az, double el)
         if (obs->L[i]==0.0&&obs->P[i]==0.0) {
             return clBlack;
         }
-        color=SnrColor(obs->SNR[i]*SNR_UNIT);
+        color=SnrColor(obs->SNR[i]);
     }
     if (el<ElMask*D2R||(ElMaskP&&el<ElMaskData[(int)(az*R2D+0.5)])) {
         return HideLowSat?clBlack:MColor[0][0];
diff --git a/app/winapp/rtkplot/plotdata.cpp b/app/winapp/rtkplot/plotdata.cpp
index 480981762..09135f35d 100644
--- a/app/winapp/rtkplot/plotdata.cpp
+++ b/app/winapp/rtkplot/plotdata.cpp
@@ -1047,7 +1047,7 @@ void __fastcall TPlot::SaveSnrMp(AnsiString file)
                 time2str(timeadd(gpst2utc(time),9*3600.0),tstr,1);
             }
             fprintf(fp,"%s %6s %8.1f %8.1f %9.2f %10.4f\n",tstr,sat,Az[j]*R2D,
-                    El[j]*R2D,Obs.data[j].SNR[k]*SNR_UNIT,!Mp[k]?0.0:Mp[k][j]);
+                    El[j]*R2D,Obs.data[j].SNR[k],!Mp[k]?0.0:Mp[k][j]);
         }
     }
     fclose(fp);
diff --git a/app/winapp/rtkplot/plotdraw.cpp b/app/winapp/rtkplot/plotdraw.cpp
index 0b79f3da4..7b6470ac6 100644
--- a/app/winapp/rtkplot/plotdraw.cpp
+++ b/app/winapp/rtkplot/plotdraw.cpp
@@ -1346,7 +1346,7 @@ void __fastcall TPlot::DrawSky(int level)
                 ustr+=" ";
                 for (j=0;j<NFREQ;j++) {
                     if (obs->P[j]==0.0&&obs->L[j]==0.0) ustr+="-- ";
-                    else ustr+=ss.sprintf("%02.0f ",obs->SNR[j]*SNR_UNIT);
+                    else ustr+=ss.sprintf("%02.0f ",obs->SNR[j]);
                 }
                 for (j=0;j<NFREQ;j++) {
                     if (obs->L[j]==0.0) ustr+="-";
@@ -1360,7 +1360,7 @@ void __fastcall TPlot::DrawSky(int level)
                               obs->P[freq-1]==0.0?"-":"C",obs->L[freq-1]==0.0?"-":"L",
                               obs->D[freq-1]==0.0?"-":"D");
                 if (obs->P[freq-1]==0.0&&obs->L[freq-1]==0.0) ustr+="---- ";
-                else ustr+=ss.sprintf("%4.1f ",obs->SNR[freq-1]*SNR_UNIT);
+                else ustr+=ss.sprintf("%4.1f ",obs->SNR[freq-1]);
                 if (obs->L[freq-1]==0.0) ustr+=" -";
                 else ustr+=ss.sprintf("%2d",obs->LLI[freq-1]);
             }
@@ -1373,7 +1373,7 @@ void __fastcall TPlot::DrawSky(int level)
                                  obs->P[j]==0.0?"-":"C",obs->L[j]==0.0?"-":"L",
                                  obs->D[j]==0.0?"-":"D");
                 if (obs->P[j]==0.0&&obs->L[j]==0.0) ustr+="---- ";
-                else ustr+=ss.sprintf("%4.1f ",obs->SNR[j]*SNR_UNIT);
+                else ustr+=ss.sprintf("%4.1f ",obs->SNR[j]);
                 if (obs->L[j]==0.0) ustr+=" -";
                 else ustr+=ss.sprintf("%2d",obs->LLI[j]);
             }
@@ -1644,11 +1644,11 @@ void __fastcall TPlot::DrawSnr(int level)
                         }
                         if (k>=NFREQ+NEXOBS) continue;
                     }
-                    if (obs->SNR[k]*SNR_UNIT<=0.0) continue;
+                    if (obs->SNR[k]<=0.0) continue;
                     
                     x[n]=TimePos(obs->time);
                     if (i==0) {
-                        y[n]=obs->SNR[k]*SNR_UNIT;
+                        y[n]=obs->SNR[k];
                         col[n]=MColor[0][4];
                     }
                     else if (i==1) {
@@ -1659,7 +1659,7 @@ void __fastcall TPlot::DrawSnr(int level)
                     else {
                         y[n]=El[j]*R2D;
                         if (SimObs) col[n]=SysColor(obs->sat);
-                        else col[n]=SnrColor(obs->SNR[k]*SNR_UNIT);
+                        else col[n]=SnrColor(obs->SNR[k]);
                         if (El[j]>0.0&&El[j]<ElMask*D2R) col[n]=MColor[0][0];
                     }
                     if (timediff(time,obs->time)==0.0&&np<MAXSAT) {
@@ -1801,10 +1801,10 @@ void __fastcall TPlot::DrawSnrE(int level)
                     }
                     if (k>=NFREQ+NEXOBS) continue;
                 }
-                if (obs->SNR[k]*SNR_UNIT<=0.0) continue;
+                if (obs->SNR[k]<=0.0) continue;
 
                 x[0][n[0]]=x[1][n[1]]=El[j]*R2D;
-                y[0][n[0]]=obs->SNR[k]*SNR_UNIT;
+                y[0][n[0]]=obs->SNR[k];
                 y[1][n[1]]=!Mp[k]?0.0:Mp[k][j];
                 
                 col[0][n[0]]=col[1][n[1]]=
@@ -2042,7 +2042,7 @@ void __fastcall TPlot::DrawRes(int level)
                 y[0][m[0]]=p->resp;
                 y[1][m[1]]=p->resc;
                 y[2][m[2]]=p->el*R2D;
-                y[3][m[3]]=p->snr*SNR_UNIT;
+                y[3][m[3]]=p->snr;
                 if      (!(p->flag>>5))  q=0; // invalid
                 else if ((p->flag&7)<=1) q=2; // float
                 else if ((p->flag&7)<=3) q=1; // fixed
diff --git a/src/pntpos.c b/src/pntpos.c
index e9759dd7b..e6fb9ded3 100644
--- a/src/pntpos.c
+++ b/src/pntpos.c
@@ -65,12 +65,12 @@ static double varerr(const prcopt_t *opt, const ssat_t *ssat, const obsd_t *obs,
     /* var = R^2*(a^2 + (b^2/sin(el) + c^2*(10^(0.1*(snr_max-snr_rover)))) + (d*rcv_std)^2) */
     varr=SQR(opt->err[1])+SQR(opt->err[2])/sin(el);
     if (opt->err[6]>0.0) {  /* if snr term not zero */
-        snr_rover=(ssat)?SNR_UNIT*ssat->snr_rover[0]:opt->err[5];
+        snr_rover=(ssat)?ssat->snr_rover[0]:opt->err[5];
         varr+=SQR(opt->err[6])*pow(10,0.1*MAX(opt->err[5]-snr_rover,0));
     }
     varr*=SQR(opt->eratio[0]);
     if (opt->err[7]>0.0) {
-        varr+=SQR(opt->err[7]*0.01*(1<<(obs->Pstd[0]+5)));  /* 0.01*2^(n+5) m */
+        varr+=SQR(opt->err[7]*obs->Pstd[0]);
     }
     if (opt->ionoopt==IONOOPT_IFLC) varr*=SQR(3.0); /* iono-free */
     return SQR(fact)*varr;
@@ -98,12 +98,12 @@ static int snrmask(const obsd_t *obs, const double *azel, const prcopt_t *opt)
 {
     int f2;
 
-    if (testsnr(0,0,azel[1],obs->SNR[0]*SNR_UNIT,&opt->snrmask)) {
+    if (testsnr(0,0,azel[1],obs->SNR[0],&opt->snrmask)) {
         return 0;
     }
     if (opt->ionoopt==IONOOPT_IFLC) {
         f2=seliflc(opt->nf,satsys(obs->sat,NULL));
-        if (testsnr(0,f2,azel[1],obs->SNR[f2]*SNR_UNIT,&opt->snrmask)) return 0;
+        if (testsnr(0,f2,azel[1],obs->SNR[f2],&opt->snrmask)) return 0;
     }
     return 1;
 }
diff --git a/src/ppp.c b/src/ppp.c
index 943487875..922da6aad 100644
--- a/src/ppp.c
+++ b/src/ppp.c
@@ -360,8 +360,8 @@ static double varerr(int sat, int sys, double el, double snr_rover,
         var+=e*e*(pow(10,0.1*MAX(snr_max-snr_rover,0)));
     }
     if (opt->err[7]>0.0) {   /* add rcvr stdevs term */
-        if (code) var+=SQR(opt->err[7]*0.01*(1<<(obs->Pstd[frq]+5))); /* 0.01*2^(n+5) */
-        else var+=SQR(opt->err[7]*obs->Lstd[frq]*0.004*0.2); /* 0.004 cycles -> m) */
+        if (code) var+=SQR(opt->err[7]*obs->Pstd[frq]);
+        else var+=SQR(opt->err[7]*obs->Lstd[frq]*0.2);
     }
     /* FIXME: the scaling factor is not 3 for other signals/constellations than GPS L1/L2 */
     var*=(opt->ionoopt==IONOOPT_IFLC)?SQR(3.0):1.0;
@@ -414,7 +414,7 @@ static void corr_meas(const obsd_t *obs, const nav_t *nav, const double *azel,
         /* skip if low SNR or missing observations */
         freq[i]=sat2freq(obs->sat,obs->code[i],nav);
         if (freq[i]==0.0||obs->L[i]==0.0||obs->P[i]==0.0) continue;
-        if (testsnr(0,0,azel[1],obs->SNR[i]*SNR_UNIT,&opt->snrmask)) continue;
+        if (testsnr(0,0,azel[1],obs->SNR[i],&opt->snrmask)) continue;
 
         /* antenna phase center and phase windup correction */
         L[i]=obs->L[i]*CLIGHT/freq[i]-dants[i]-dantr[i]-phw*CLIGHT/freq[i];
@@ -1045,7 +1045,7 @@ static int ppp_res(int post, const obsd_t *obs, int n, const double *rs,
 
             /* variance */
             var[nv]=varerr(sat,sys,azel[1+i*2],
-                    SNR_UNIT*rtk->ssat[sat-1].snr_rover[frq],
+                    rtk->ssat[sat-1].snr_rover[frq],
                     j,opt,obs+i);
             var[nv] +=vart+SQR(C)*vari+var_rs[i];
             if (sys==SYS_GLO&&code==1) var[nv]+=VAR_GLO_IFB;
diff --git a/src/rcv/binex.c b/src/rcv/binex.c
index a9b02fa45..596bcf85e 100644
--- a/src/rcv/binex.c
+++ b/src/rcv/binex.c
@@ -976,8 +976,8 @@ static uint8_t *decode_bnx_7f_05_obs(raw_t *raw, uint8_t *buff, int sat,
         }
         if (k<0) {
             data->P[i]=data->L[i]=0.0;
-            data->D[i]=0.0f;
-            data->SNR[i]=data->LLI[i]=0;
+            data->D[i]=data->SNR[i]=0.0;
+            data->LLI[i]=0;
             data->code[i]=CODE_NONE;
         }
         else {
@@ -985,7 +985,7 @@ static uint8_t *decode_bnx_7f_05_obs(raw_t *raw, uint8_t *buff, int sat,
             data->P[i]=range[k];
             data->L[i]=phase[k]*freq/CLIGHT;
             data->D[i]=dopp[k];
-            data->SNR[i]=(uint16_t)(cnr[k]/SNR_UNIT+0.5);
+            data->SNR[i]=cnr[k];
             data->code[i]=codes[code[k]];
             data->LLI[i]=slip[k]?1:0;
             mask[k]=1;
@@ -997,8 +997,8 @@ static uint8_t *decode_bnx_7f_05_obs(raw_t *raw, uint8_t *buff, int sat,
         }
         if (k>=nobs) {
             data->P[i]=data->L[i]=0.0;
-            data->D[i]=0.0f;
-            data->SNR[i]=data->LLI[i]=0;
+            data->D[i]=data->SNR[i]=0.0;
+            data->LLI[i]=0;
             data->code[i]=CODE_NONE;
         }
         else {
@@ -1006,7 +1006,7 @@ static uint8_t *decode_bnx_7f_05_obs(raw_t *raw, uint8_t *buff, int sat,
             data->P[i]=range[k];
             data->L[i]=phase[k]*freq/CLIGHT;
             data->D[i]=dopp[k];
-            data->SNR[i]=(uint16_t)(cnr[k]/SNR_UNIT+0.5);
+            data->SNR[i]=cnr[k];
             data->code[i]=codes[code[k]];
             data->LLI[i]=slip[k]?1:0;
             mask[k]=1;
diff --git a/src/rcv/comnav.c b/src/rcv/comnav.c
index a3f39524e..7752de95c 100644
--- a/src/rcv/comnav.c
+++ b/src/rcv/comnav.c
@@ -84,8 +84,8 @@ static int obsindex(obs_t *obs, gtime_t time, int sat)
     obs->data[i].sat=sat;
     for (j=0;j<NFREQ+NEXOBS;j++) {
         obs->data[i].L[j]=obs->data[i].P[j]=0.0;
-        obs->data[i].D[j]=0.0;
-        obs->data[i].SNR[j]=obs->data[i].LLI[j]=0;
+        obs->data[i].D[j]=obs->data[i].SNR[j]=0.0;
+        obs->data[i].LLI[j]=0;
         obs->data[i].code[j]=CODE_NONE;
     }
     obs->n++;
@@ -299,8 +299,7 @@ static int decode_rangecmpb(raw_t *raw)
             raw->obs.data[index].L  [pos]=adr;
             raw->obs.data[index].P  [pos]=psr;
             raw->obs.data[index].D  [pos]=(float)dop;
-            raw->obs.data[index].SNR[pos]=
-                0.0<=snr&&snr<255.0?(unsigned char)(snr*4.0+0.5):0;
+            raw->obs.data[index].SNR[pos]=0.0<=snr&&snr<255.0?snr:0;
             raw->obs.data[index].LLI[pos]=(unsigned char)lli;
             raw->obs.data[index].code[pos]=code;
 #if 0
@@ -388,8 +387,7 @@ static int decode_rangeb(raw_t *raw)
             raw->obs.data[index].L  [pos]=-adr;
             raw->obs.data[index].P  [pos]=psr;
             raw->obs.data[index].D  [pos]=(float)dop;
-            raw->obs.data[index].SNR[pos]=
-                0.0<=snr&&snr<255.0?(unsigned char)(snr*4.0+0.5):0;
+            raw->obs.data[index].SNR[pos]=0.0<=snr&&snr<255.0?snr:0;
             raw->obs.data[index].LLI[pos]=(unsigned char)lli;
             raw->obs.data[index].code[pos]=code;
 #if 0
diff --git a/src/rcv/crescent.c b/src/rcv/crescent.c
index df9c37a28..926621daa 100644
--- a/src/rcv/crescent.c
+++ b/src/rcv/crescent.c
@@ -145,14 +145,14 @@ static int decode_cresraw(raw_t *raw)
         raw->obs.data[n].P[0]=pr;
         raw->obs.data[n].L[0]=cp*freq/CLIGHT;
         raw->obs.data[n].D[0]=-(float)(dop*freq/CLIGHT);
-        raw->obs.data[n].SNR[0]=(uint16_t)(snr/SNR_UNIT+0.5);
+        raw->obs.data[n].SNR[0]=snr;
         raw->obs.data[n].LLI[0]=(uint8_t)lli;
         raw->obs.data[n].code[0]=CODE_L1C;
         
         for (j=1;j<NFREQ;j++) {
             raw->obs.data[n].L[j]=raw->obs.data[n].P[j]=0.0;
-            raw->obs.data[n].D[j]=0.0;
-            raw->obs.data[n].SNR[j]=raw->obs.data[n].LLI[j]=0;
+            raw->obs.data[n].D[j]=raw->obs.data[n].SNR[j]=0.0;
+            raw->obs.data[n].LLI[j]=0;
             raw->obs.data[n].code[j]=CODE_NONE;
         }
         n++;
@@ -256,14 +256,14 @@ static int decode_cresraw2(raw_t *raw)
                 raw->obs.data[n].P[j]=pr[j]==0.0?0.0:pr[j]-toff;
                 raw->obs.data[n].L[j]=cp[j]==0.0?0.0:cp[j]-toff*freq[j]/CLIGHT;
                 raw->obs.data[n].D[j]=-(float)dop[j];
-                raw->obs.data[n].SNR[j]=(uint16_t)(snr[j]/SNR_UNIT+0.5);
+                raw->obs.data[n].SNR[j]=snr[j];
                 raw->obs.data[n].LLI[j]=(uint8_t)lli[j];
                 raw->obs.data[n].code[j]=j==0?CODE_L1C:CODE_L2P;
             }
             else {
                 raw->obs.data[n].L[j]=raw->obs.data[n].P[j]=0.0;
-                raw->obs.data[n].D[j]=0.0;
-                raw->obs.data[n].SNR[j]=raw->obs.data[n].LLI[j]=0;
+                raw->obs.data[n].D[j]=raw->obs.data[n].SNR[j]=0.0;
+                raw->obs.data[n].LLI[j]=0;
                 raw->obs.data[n].code[j]=CODE_NONE;
             }
         }
@@ -461,14 +461,14 @@ static int decode_cresgloraw(raw_t *raw)
                 raw->obs.data[n].P[j]=pr[j]==0.0?0.0:pr[j]-toff;
                 raw->obs.data[n].L[j]=cp[j]==0.0?0.0:cp[j]-toff*freq[j]/CLIGHT;
                 raw->obs.data[n].D[j]=-(float)dop[j];
-                raw->obs.data[n].SNR[j]=(uint16_t)(snr[j]/SNR_UNIT+0.5);
+                raw->obs.data[n].SNR[j]=snr[j];
                 raw->obs.data[n].LLI[j]=(uint8_t)lli[j];
                 raw->obs.data[n].code[j]=j==0?CODE_L1C:CODE_L2P;
             }
             else {
                 raw->obs.data[n].L[j]=raw->obs.data[n].P[j]=0.0;
-                raw->obs.data[n].D[j]=0.0;
-                raw->obs.data[n].SNR[j]=raw->obs.data[n].LLI[j]=0;
+                raw->obs.data[n].D[j]=raw->obs.data[n].SNR[j]=0.0;
+                raw->obs.data[n].LLI[j]=0;
                 raw->obs.data[n].code[j]=CODE_NONE;
             }
         }
diff --git a/src/rcv/javad.c b/src/rcv/javad.c
index 37d090a45..ce4222f5a 100644
--- a/src/rcv/javad.c
+++ b/src/rcv/javad.c
@@ -232,8 +232,8 @@ static int flushobuf(raw_t *raw)
         raw->obuf.data[i].time=time0;
         for (j=0;j<NFREQ+NEXOBS;j++) {
             raw->obuf.data[i].L[j]=raw->obuf.data[i].P[j]=0.0;
-            raw->obuf.data[i].D[j]=0.0;
-            raw->obuf.data[i].SNR[j]=raw->obuf.data[i].LLI[j]=0;
+            raw->obuf.data[i].D[j]=raw->obuf.data[i].SNR[j]=0.0;
+            raw->obuf.data[i].LLI[j]=0;
             raw->obuf.data[i].code[j]=CODE_NONE;
         }
     }
@@ -1560,7 +1560,7 @@ static int decode_Ex(raw_t *raw, char sig)
         
         if ((idx=checkpri(sys,code,raw->opt,idx))>=0) {
             if (!settag(raw->obuf.data+i,raw->time)) continue;
-            raw->obuf.data[i].SNR[idx]=(uint16_t)(cnr/SNR_UNIT+0.5);
+            raw->obuf.data[i].SNR[idx]=cnr;
         }
     }
     return 0;
@@ -1591,7 +1591,7 @@ static int decode_xE(raw_t *raw, char sig)
         
         if ((idx=checkpri(sys,code,raw->opt,idx))>=0) {
             if (!settag(raw->obuf.data+i,raw->time)) continue;
-            raw->obuf.data[i].SNR[idx]=(uint16_t)(cnr*0.25/SNR_UNIT+0.5);
+            raw->obuf.data[i].SNR[idx]=cnr*0.25;
         }
     }
     return 0;
diff --git a/src/rcv/novatel.c b/src/rcv/novatel.c
index 16f656845..19ff68036 100644
--- a/src/rcv/novatel.c
+++ b/src/rcv/novatel.c
@@ -177,8 +177,8 @@ static int obsindex(obs_t *obs, gtime_t time, int sat)
     obs->data[i].sat=sat;
     for (j=0;j<NFREQ+NEXOBS;j++) {
         obs->data[i].L[j]=obs->data[i].P[j]=0.0;
-        obs->data[i].D[j]=0.0;
-        obs->data[i].SNR[j]=obs->data[i].LLI[j]=0;
+        obs->data[i].D[j]=obs->data[i].SNR[j]=0.0;
+        obs->data[i].LLI[j]=0;
         obs->data[i].code[j]=CODE_NONE;
     }
     obs->n++;
@@ -432,7 +432,7 @@ static int decode_rangecmpb(raw_t *raw)
             raw->obs.data[index].L  [idx]=adr;
             raw->obs.data[index].P  [idx]=psr;
             raw->obs.data[index].D  [idx]=(float)dop;
-            raw->obs.data[index].SNR[idx]=(uint16_t)(snr/SNR_UNIT+0.5);
+            raw->obs.data[index].SNR[idx]=snr;
             raw->obs.data[index].LLI[idx]=(uint8_t)lli;
             raw->obs.data[index].code[idx]=(uint8_t)code;
         }
@@ -515,7 +515,7 @@ static int decode_rangeb(raw_t *raw)
             raw->obs.data[index].L  [idx]=-adr;
             raw->obs.data[index].P  [idx]=psr;
             raw->obs.data[index].D  [idx]=(float)dop;
-            raw->obs.data[index].SNR[idx]=(uint16_t)(snr/SNR_UNIT+0.5);
+            raw->obs.data[index].SNR[idx]=snr;
             raw->obs.data[index].LLI[idx]=(uint8_t)lli;
             raw->obs.data[index].code[idx]=(uint8_t)code;
         }
@@ -1107,8 +1107,7 @@ static int decode_rgeb(raw_t *raw)
             raw->obs.data[index].L  [freq]=-adr; /* flip sign */
             raw->obs.data[index].P  [freq]=psr;
             raw->obs.data[index].D  [freq]=(float)dop;
-            raw->obs.data[index].SNR[freq]=
-                0.0<=snr&&snr<255.0?(uint16_t)(snr/SNR_UNIT+0.5):0;
+            raw->obs.data[index].SNR[freq]=0.0<=snr&&snr<255.0?snr:0;
             raw->obs.data[index].LLI[freq]=(uint8_t)lli;
             raw->obs.data[index].code[freq]=freq==0?CODE_L1C:CODE_L2P;
         }
@@ -1173,7 +1172,7 @@ static int decode_rged(raw_t *raw)
             raw->obs.data[index].L  [freq]=adr;
             raw->obs.data[index].P  [freq]=psr;
             raw->obs.data[index].D  [freq]=(float)dop;
-            raw->obs.data[index].SNR[freq]=(uint16_t)(snr/SNR_UNIT+0.5);
+            raw->obs.data[index].SNR[freq]=snr;
             raw->obs.data[index].LLI[freq]=(uint8_t)lli;
             raw->obs.data[index].code[freq]=freq==0?CODE_L1C:CODE_L2P;
         }
diff --git a/src/rcv/nvs.c b/src/rcv/nvs.c
index e70a976ad..875a48374 100644
--- a/src/rcv/nvs.c
+++ b/src/rcv/nvs.c
@@ -145,7 +145,7 @@ static int decode_xf5raw(raw_t *raw)
                   sat,L1,P1,D1);
             continue;
         }
-        raw->obs.data[n].SNR[0]=(uint16_t)(I1(p+3)/SNR_UNIT+0.5);
+        raw->obs.data[n].SNR[0]=I1(p+3);
         if (sys==SYS_GLO) {
             raw->obs.data[n].L[0]  =  L1 - toff*(FREQ1_GLO+DFRQ1_GLO*carrNo);
         } else {
@@ -164,8 +164,8 @@ static int decode_xf5raw(raw_t *raw)
         
         for (j=1;j<NFREQ+NEXOBS;j++) {
             raw->obs.data[n].L[j]=raw->obs.data[n].P[j]=0.0;
-            raw->obs.data[n].D[j]=0.0;
-            raw->obs.data[n].SNR[j]=raw->obs.data[n].LLI[j]=0;
+            raw->obs.data[n].D[j]=raw->obs.data[n].SNR[j]=0.0;
+            raw->obs.data[n].LLI[j]=0;
             raw->obs.data[n].code[j]=CODE_NONE;
         }
         n++;
diff --git a/src/rcv/rt17.c b/src/rcv/rt17.c
index 31d1fcb85..8ebe4b04f 100644
--- a/src/rcv/rt17.c
+++ b/src/rcv/rt17.c
@@ -1701,7 +1701,7 @@ static int DecodeType17(raw_t *Raw, uint32_t rif)
             if (Flags1 & M_BIT6) /* L1 data valid */
             {
                 /* Measure of L1 signal strength (dB * 4) */
-                obs->SNR[0] = (uint16_t)(U1(p)*0.25/SNR_UNIT+0.5);
+                obs->SNR[0] = U1(p)*0.25;
                 p++;
                 
                 /* Full L1 C/A code or P-code pseudorange (meters) */
@@ -1721,7 +1721,7 @@ static int DecodeType17(raw_t *Raw, uint32_t rif)
             if (Flags1 & M_BIT0)  /* L2 data loaded */
             {
                 /* Measure of L2 signal strength (dB * 4) */
-                obs->SNR[1] = (uint16_t)(U1(p)*0.25/SNR_UNIT+0.5);
+                obs->SNR[1] = U1(p)*0.25;
                 p++;
                 
                 /* L2 Continuous Phase (cycles) */
@@ -1780,7 +1780,7 @@ static int DecodeType17(raw_t *Raw, uint32_t rif)
             if (Flags1 & M_BIT6) /* L1 data valid */
             {           
                 /* Measure of satellite signal strength (dB) */
-                obs->SNR[0] = (uint16_t)(R8(p)/SNR_UNIT+0.5);
+                obs->SNR[0] = R8(p);
                 p += 8;
 
                 /* Full L1 C/A code or P-code pseudorange (meters) */
@@ -1803,7 +1803,7 @@ static int DecodeType17(raw_t *Raw, uint32_t rif)
             if (Flags1 & M_BIT0) /* L2 data loaded */
             {
                 /* Measure of L2 signal strength (dB) */
-                obs->SNR[1] = (uint16_t)(R8(p)/SNR_UNIT+0.5);
+                obs->SNR[1] = R8(p);
                 p += 8;
 
                 /* L2 Continuous Phase (cycles) */                
diff --git a/src/rcv/septentrio.c b/src/rcv/septentrio.c
index b27c46ab2..a97b88c8a 100644
--- a/src/rcv/septentrio.c
+++ b/src/rcv/septentrio.c
@@ -583,10 +583,9 @@ static void init_obsd(gtime_t time, int sat, obsd_t *data)
 
     for (i = 0; i < NFREQ+NEXOBS; i++) {
         data->L[i] = data->P[i] = 0.0;
-        data->D[i] = 0.0f;
+        data->D[i] = data->SNR[i] = 0.0;
         data->Lstd[i] = data->Pstd[i] = 0.0;
-        data->SNR[i] = (uint16_t)0;
-        data->LLI[i] = (uint8_t)0;
+        data->LLI[i] = 0;
         data->code[i] = CODE_NONE;
     }
 }
@@ -668,9 +667,9 @@ static int flushobuf(raw_t *raw) {
         raw->obuf.data[i].time.sec = 0;
         for (j = 0; j < NFREQ + NEXOBS; j++) {
             raw->obuf.data[i].L[j] = raw->obuf.data[i].P[j] = 0.0;
+            raw->obuf.data[i].D[j] = raw->obuf.data[i].SNR[j] = 0.0;
             raw->obuf.data[i].Lstd[j] = raw->obuf.data[i].Pstd[j] = 0.0;
-            raw->obuf.data[i].D[j] = 0.0;
-            raw->obuf.data[i].SNR[j] = raw->obuf.data[i].LLI[j] = 0;
+            raw->obuf.data[i].LLI[j] = 0;
             raw->obuf.data[i].code[j] = CODE_NONE;
         }
     }
@@ -788,7 +787,7 @@ static int decode_measepoch(raw_t *raw)
         }
         if (U1(p+15) != 255) {
             S1 = U1(p+15)*0.25 + ((sig==1 || sig==2) ? 0.0 : 10.0);
-            raw->obuf.data[n].SNR[idx] = (uint16_t)(S1/SNR_UNIT+0.5);
+            raw->obuf.data[n].SNR[idx] = S1;
         }
         raw->obuf.data[n].code[idx] = code;
 
@@ -816,7 +815,7 @@ static int decode_measepoch(raw_t *raw)
             }
             if (U1(p+2) != 255) {
                 S2 = U1(p+2)*0.25 + ((sig==1 || sig==2) ? 0.0 : 10.0);
-                raw->obuf.data[n].SNR[idx] = (uint16_t)(S2/SNR_UNIT+0.5);
+                raw->obuf.data[n].SNR[idx] = S2;
             }
             if (P1!=0.0 && (getbits(p+3, 5, 3)!=-4 || U2(p+6)!=0)) {
                 P2 = P1+getbits(p+3, 5, 3)*65.536 + U2(p+6)*0.001;
@@ -898,31 +897,20 @@ static int decode_measepochextra(raw_t *raw)
         if (rcvstds) {
             uint16_t codeVarU = U2(p_chan + 6);
             if (codeVarU != 65535) {
-                double codeVar = codeVarU / 10000.;   /* meters^2 */
-                // To RTKlib encoding
-                // TODO starting from 2 rather than 5 would better suit here
-                double pstd = log2(sqrt(codeVar) * 100) - 5;
-                pstd = pstd > 0 ? pstd : 0;
-                /* Further limited to 9 in RINEX output */
-                pstd = pstd <= 254 ? pstd : 254;
-                raw->obuf.data[n].Pstd[idx] = pstd + 0.5;
+                double codeVar = codeVarU / 10000.0;   /* meters^2 */
+                raw->obuf.data[n].Pstd[idx] = sqrt(codeVar);
             }
 
             uint16_t carrierVarU = U2(p_chan + 8);
             if (carrierVarU != 65535) {
-                double carrierVar = carrierVarU / 1000000.; /* cycles^2 */
-                // To RTKlib encoding
-                double lstd = sqrt(carrierVar) / 0.004;
-                lstd = lstd > 0 ? lstd : 0;
-                /* Further limited to 9 in RINEX output */
-                lstd = lstd <= 254 ? lstd : 254;
-                raw->obuf.data[n].Lstd[idx] = lstd + 0.5;
+                double carrierVar = carrierVarU / 1000000.0; /* cycles^2 */
+                raw->obuf.data[n].Lstd[idx] = sqrt(carrierVar);
             }
         }
 
         if ((revision >= 3) && (sbLen >= 16)) {  /* later revision contains high-resolution extension for CN0 values*/
             misc = U1(p_chan+15);
-            raw->obuf.data[n].SNR[idx] = (uint16_t)((raw->obuf.data[n].SNR[idx] * SNR_UNIT + (misc & 0x7) * 0.03125) / SNR_UNIT + 0.5);
+            raw->obuf.data[n].SNR[idx] += (misc & 0x7) * 0.03125;
         }
     }
 
@@ -1099,7 +1087,7 @@ static int decode_meas3ranges(raw_t *raw) {
                         freqMaster = code2freq(Meas3_NavSys[navsys], codeMaster, glofnc);
                         double pr = prbase + ((double)pr_lsb + 4294967296.0 * (double)prMsb) * .001;
                         raw->obuf.data[n].P[masterFreqIndex] = pr;
-                        raw->obuf.data[n].SNR[masterFreqIndex] = (uint16_t)((CN0 + 24.0)/SNR_UNIT+0.5);
+                        raw->obuf.data[n].SNR[masterFreqIndex] = CN0 + 24.0;
                         raw->obuf.data[n].code[masterFreqIndex] = codeMaster;
                         if (cmc != 0)
                             raw->obuf.data[n].L[masterFreqIndex] = pr / (CLIGHT/freqMaster) - 131.072 + (double)cmc * .001;
@@ -1145,7 +1133,7 @@ static int decode_meas3ranges(raw_t *raw) {
                         uint8_t isGPSPCode = (navsys == 0) && (codeMaster == CODE_L1W || codeMaster == CODE_L2W);
 
                         raw->obuf.data[n].P[masterFreqIndex] = ((double)prLsb + 4294967296.0 * (double)prMsb) * .001;
-                        raw->obuf.data[n].SNR[masterFreqIndex] = (uint16_t)((isGPSPCode ? CN0 : CN0 + 10.0) / SNR_UNIT + 0.5);
+                        raw->obuf.data[n].SNR[masterFreqIndex] = isGPSPCode ? CN0 : CN0 + 10.0;
                         raw->obuf.data[n].code[masterFreqIndex] = codeMaster;
                         if (cmc != 0)
                             raw->obuf.data[n].L[masterFreqIndex] = raw->obuf.data[n].P[masterFreqIndex] / (CLIGHT/freqMaster) - 2097.152 + (double)cmc * .001;
@@ -1180,7 +1168,7 @@ static int decode_meas3ranges(raw_t *raw) {
                         raw->obuf.data[n].P[masterFreqIndex] = master_reference->P[masterFreqIndex] +
                                                        ((int64_t)sbf->meas3_refEpoch.prRate[navsys][svid] * 64 * (int32_t)(TOW % refEpochInterval) / 1000) * .001 +
                                                        (double)pr * .001 - 65.536;
-                        raw->obuf.data[n].SNR[masterFreqIndex] = (uint16_t)((master_reference->SNR[masterFreqIndex] * SNR_UNIT - 4.0 + CN0) / SNR_UNIT + 0.5);
+                        raw->obuf.data[n].SNR[masterFreqIndex] = master_reference->SNR[masterFreqIndex] - 4.0 + CN0;
                         raw->obuf.data[n].code[masterFreqIndex] = codeMaster;
                         if (cmc != 0)
                             raw->obuf.data[n].L[masterFreqIndex] = (raw->obuf.data[n].P[masterFreqIndex] - master_reference->P[masterFreqIndex]) / (CLIGHT/freqMaster) +
@@ -1211,7 +1199,7 @@ static int decode_meas3ranges(raw_t *raw) {
                         raw->obuf.data[n].P[masterFreqIndex] = masterReference->P[masterFreqIndex] + ((int64_t)sbf->meas3_refEpoch.prRate[navsys][svid] * 64 * (int32_t)(TOW % refEpochInterval) / 1000) * .001 + (double)pr * .001 - 8.192;
                         if (cmc != 0)
                             raw->obuf.data[n].L[masterFreqIndex] = (raw->obuf.data[n].P[masterFreqIndex] - masterReference->P[masterFreqIndex]) / (CLIGHT/freqMaster) + masterReference->L[masterFreqIndex] - 8.192 + (double)cmc * .001;
-                        raw->obuf.data[n].SNR[masterFreqIndex] = (uint16_t)((masterReference->SNR[masterFreqIndex] * SNR_UNIT - 1.0 + CN0) / SNR_UNIT + 0.5);
+                        raw->obuf.data[n].SNR[masterFreqIndex] = masterReference->SNR[masterFreqIndex] - 1.0 + CN0;
                         raw->obuf.data[n].LLI[masterFreqIndex] = masterReference->LLI[masterFreqIndex];
                         raw->lockt[satNo-1][masterFreqIndex] = sbf->meas3_refEpoch.lockt[navsys][svid][masterFreqIndex];
                         raw->obuf.data[n].code[masterFreqIndex] = codeMaster;
@@ -1282,9 +1270,9 @@ static int decode_meas3ranges(raw_t *raw) {
                                                           - 32.768 + cmcRes * .001;
 
                                 if ((navsys == 0) && (codeSlave == CODE_L1W || codeSlave == CODE_L2W))
-                                    raw->obuf.data[n].SNR[slaveFreqIndex] = (uint16_t)((raw->obuf.data[n].SNR[masterFreqIndex] * SNR_UNIT - 3.0 - CN0) / SNR_UNIT + 0.5);
+                                    raw->obuf.data[n].SNR[slaveFreqIndex] = raw->obuf.data[n].SNR[masterFreqIndex] - 3.0 - CN0;
                                 else
-                                    raw->obuf.data[n].SNR[slaveFreqIndex] = (uint16_t)((CN0 + 24.0) / SNR_UNIT + 0.5);
+                                    raw->obuf.data[n].SNR[slaveFreqIndex] = CN0 + 24.0;
 
                                 raw->obuf.data[n].code[slaveFreqIndex] = codeSlave;
                                 raw->obuf.data[n].LLI[slaveFreqIndex] = (lockTime < raw->lockt[satNo-1][slaveFreqIndex] ? LLI_SLIP : 0) | (lti3 == 0 ? LLI_HALFC : 0);
@@ -1313,9 +1301,9 @@ static int decode_meas3ranges(raw_t *raw) {
                                     raw->obuf.data[n].L[slaveFreqIndex] = raw->obuf.data[n].P[slaveFreqIndex] / (CLIGHT/freqSlave) - 2097.152 + cmc * 0.001;
 
                                 if ((navsys == 0) && (codeSlave == CODE_L1W || codeSlave == CODE_L2W))
-                                    raw->obuf.data[n].SNR[slaveFreqIndex] = (uint16_t)(CN0 / SNR_UNIT + 0.5);
+                                    raw->obuf.data[n].SNR[slaveFreqIndex] = CN0;
                                 else
-                                    raw->obuf.data[n].SNR[slaveFreqIndex] = (uint16_t)((CN0 + 10.0) / SNR_UNIT + 0.5);
+                                    raw->obuf.data[n].SNR[slaveFreqIndex] = CN0 + 10.0;
 
                                 raw->obuf.data[n].code[slaveFreqIndex] = codeSlave;
                                 raw->obuf.data[n].LLI[slaveFreqIndex] = (lockTime < raw->lockt[satNo-1][slaveFreqIndex] ? LLI_SLIP : 0) | (lti4 == 0 ? LLI_HALFC : 0);
@@ -1347,7 +1335,7 @@ static int decode_meas3ranges(raw_t *raw) {
                                                                       (raw->obuf.data[n].L[slaveFreqIndex] - slaveReference->L[slaveRefFreqIdx]) * (CLIGHT/freqSlave)
                                                                       - 2.048 + dPr * 0.001);
 
-                                raw->obuf.data[n].SNR[slaveFreqIndex] = (uint16_t)(slaveReference->SNR[slaveRefFreqIdx] + (-2.0 + CN0)/SNR_UNIT+0.5);
+                                raw->obuf.data[n].SNR[slaveFreqIndex] = slaveReference->SNR[slaveRefFreqIdx] - 2.0 + CN0;
 
                                 raw->obuf.data[n].code[slaveFreqIndex] = codeSlave;
                                 raw->obuf.data[n].LLI[slaveFreqIndex] = slaveReference->LLI[slaveRefFreqIdx];
@@ -1525,13 +1513,13 @@ int decode_meas3CN(raw_t* raw)
         masterFreqIndex = sbf->meas3_freqAssignment[navsys][svid][0];
 
         uint8_t mc = (U1(raw->buff + 16 + offset / 2) >> ((offset % 2) * 4)) & 0xf;
-        raw->obuf.data[n].SNR[masterFreqIndex] += (mc * 0.0625 - 0.5) / SNR_UNIT + 0.5;
+        raw->obuf.data[n].SNR[masterFreqIndex] += mc * 0.0625 - 0.5;
         offset++;
         for (int i = 1; i<MEAS3_SIG_MAX; i++) {
             slaveFreqIndex = sbf->meas3_freqAssignment[navsys][svid][i];
             if (slaveFreqIndex < 0)
                 break;
-            raw->obuf.data[n].SNR[slaveFreqIndex] += (((U1(raw->buff + 16 + offset / 2) >> ((offset % 2) * 4)) & 0xf) * .0625F - 0.5F)/SNR_UNIT + 0.5;
+            raw->obuf.data[n].SNR[slaveFreqIndex] += ((U1(raw->buff + 16 + offset / 2) >> ((offset % 2) * 4)) & 0xf) * .0625 - 0.5;
             offset++;
         }
     }
diff --git a/src/rcv/skytraq.c b/src/rcv/skytraq.c
index ac8d70869..ce84cf410 100644
--- a/src/rcv/skytraq.c
+++ b/src/rcv/skytraq.c
@@ -270,7 +270,7 @@ static int decode_stqraw(raw_t *raw)
         raw->obs.data[n].P[0]=pr1;
         raw->obs.data[n].L[0]=cp1;
         raw->obs.data[n].D[0]=!(ind&2)?0.0:R4(p+18);
-        raw->obs.data[n].SNR[0]=(uint16_t)(U1(p+1)/SNR_UNIT+0.5);
+        raw->obs.data[n].SNR[0]=U1(p+1);
         raw->obs.data[n].LLI[0]=0;
         raw->obs.data[n].code[0]=sys==SYS_CMP?CODE_L2I:CODE_L1C;
         
@@ -289,8 +289,8 @@ static int decode_stqraw(raw_t *raw)
         
         for (j=1;j<NFREQ+NEXOBS;j++) {
             raw->obs.data[n].L[j]=raw->obs.data[n].P[j]=0.0;
-            raw->obs.data[n].D[j]=0.0;
-            raw->obs.data[n].SNR[j]=raw->obs.data[n].LLI[j]=0;
+            raw->obs.data[n].D[j]=raw->obs.data[n].SNR[j]=0.0;
+            raw->obs.data[n].LLI[j]=0;
             raw->obs.data[n].code[j]=CODE_NONE;
         }
         n++;
@@ -349,8 +349,8 @@ static int decode_stqrawx(raw_t *raw)
             raw->obs.data[n].rcv=0;
             for (k=0;k<NFREQ+NEXOBS;k++) {
                 raw->obs.data[n].L[k]=raw->obs.data[n].P[k]=0.0;
-                raw->obs.data[n].D[k]=0.0;
-                raw->obs.data[n].SNR[k]=raw->obs.data[n].LLI[k]=0;
+                raw->obs.data[n].D[k]=raw->obs.data[n].SNR[k]=0.0;
+                raw->obs.data[n].LLI[k]=0;
                 raw->obs.data[n].code[k]=CODE_NONE;
             }
             n++;
@@ -358,7 +358,7 @@ static int decode_stqrawx(raw_t *raw)
         raw->obs.data[j].P[idx]=pr1;
         raw->obs.data[j].L[idx]=cp1;
         raw->obs.data[j].D[idx]=!(ind&2)?0.0:R4(p+20);
-        raw->obs.data[j].SNR[idx]=(uint16_t)(U1(p+3)/SNR_UNIT+0.5);
+        raw->obs.data[j].SNR[idx]=U1(p+3);
         raw->obs.data[j].LLI[idx]=0;
         raw->obs.data[j].code[idx]=sig;
 
diff --git a/src/rcv/swiftnav.c b/src/rcv/swiftnav.c
index 58828a7ee..2fba8f2e3 100644
--- a/src/rcv/swiftnav.c
+++ b/src/rcv/swiftnav.c
@@ -396,8 +396,8 @@ static int flushobuf(raw_t *raw) {
     raw->obuf.data[i].time = time0;
     for (j = 0; j < NFREQ + NEXOBS; j++) {
       raw->obuf.data[i].L[j] = raw->obuf.data[i].P[j] = 0.0;
-      raw->obuf.data[i].D[j] = 0.0;
-      raw->obuf.data[i].SNR[j] = raw->obuf.data[i].LLI[j] = 0;
+      raw->obuf.data[i].D[j] = raw->obuf.data[i].SNR[j] = 0.0;
+      raw->obuf.data[i].LLI[j] = 0;
       raw->obuf.data[i].code[j] = CODE_NONE;
     }
   }
@@ -533,7 +533,7 @@ static int decode_msgobs(raw_t *raw) {
       raw->obuf.data[ii].P[freq] = (flags & 0x1) ? pseudorange : 0.0;
       raw->obuf.data[ii].L[freq] = (flags & 0x2) ? carr_phase : 0.0;
       raw->obuf.data[ii].D[freq] = (flags & 0x8) ? (float)freq_doppler : 0.0f;
-      raw->obuf.data[ii].SNR[freq] = (cn0_int*0.25/SNR_UNIT+0.5);
+      raw->obuf.data[ii].SNR[freq] = cn0_int * 0.25;
       raw->obuf.data[ii].code[freq] = code;
 
       if (flags & 0x2) {
diff --git a/src/rcv/tersus.c b/src/rcv/tersus.c
index 207ceba80..e04917476 100644
--- a/src/rcv/tersus.c
+++ b/src/rcv/tersus.c
@@ -67,8 +67,8 @@ static int obsindex(obs_t *obs, gtime_t time, int sat)
     obs->data[i].sat=sat;
     for (j=0;j<NFREQ+NEXOBS;j++) {
         obs->data[i].L[j]=obs->data[i].P[j]=0.0;
-        obs->data[i].D[j]=0.0;
-        obs->data[i].SNR[j]=obs->data[i].LLI[j]=0;
+        obs->data[i].D[j]=obs->data[i].SNR[j]=0.0;
+        obs->data[i].LLI[j]=0;
         obs->data[i].code[j]=CODE_NONE;
     }
     obs->n++;
@@ -262,8 +262,7 @@ static int decode_rangeb(raw_t *raw)
             raw->obs.data[index].L  [pos]=-adr;
             raw->obs.data[index].P  [pos]=psr;
             raw->obs.data[index].D  [pos]=(float)dop;
-            raw->obs.data[index].SNR[pos]=
-                0.0<=snr&&snr<255.0?(unsigned char)(snr*4.0+0.5):0;
+            raw->obs.data[index].SNR[pos]=0.0<=snr&&snr<255.0?snr:0;
             raw->obs.data[index].LLI[pos]=(unsigned char)lli;
             raw->obs.data[index].code[pos]=code;
         }
@@ -347,8 +346,7 @@ static int decode_rangecmpb(raw_t *raw)
             raw->obs.data[index].L  [pos]=adr;
             raw->obs.data[index].P  [pos]=psr;
             raw->obs.data[index].D  [pos]=(float)dop;
-            raw->obs.data[index].SNR[pos]=
-                0.0<=snr&&snr<255.0?(unsigned char)(snr*4.0+0.5):0;
+            raw->obs.data[index].SNR[pos]=0.0<=snr&&snr<255.0?snr:0;
             raw->obs.data[index].LLI[pos]=(unsigned char)lli;
             raw->obs.data[index].code[pos]=code;
         }
diff --git a/src/rcv/ublox.c b/src/rcv/ublox.c
index c66730522..322093d7f 100644
--- a/src/rcv/ublox.c
+++ b/src/rcv/ublox.c
@@ -320,7 +320,7 @@ static int decode_rxmraw(raw_t *raw)
         raw->obs.data[n].P[0]  =R8(p+ 8)-toff*CLIGHT;
         raw->obs.data[n].D[0]  =R4(p+16);
         prn                    =U1(p+20);
-        raw->obs.data[n].SNR[0]=(uint16_t)(I1(p+22)*1.0/SNR_UNIT+0.5);
+        raw->obs.data[n].SNR[0]=I1(p+22);
         raw->obs.data[n].LLI[0]=U1(p+23);
         raw->obs.data[n].code[0]=CODE_L1C;
         
@@ -340,9 +340,9 @@ static int decode_rxmraw(raw_t *raw)
         
         for (j=1;j<NFREQ+NEXOBS;j++) {
             raw->obs.data[n].L[j]=raw->obs.data[n].P[j]=0.0;
-            raw->obs.data[n].D[j]=0.0;
-            raw->obs.data[n].SNR[j]=raw->obs.data[n].LLI[j]=0;
-            raw->obs.data[n].Lstd[j]=raw->obs.data[n].Pstd[j]=0;
+            raw->obs.data[n].D[j]=raw->obs.data[n].SNR[j]=0.0;
+            raw->obs.data[n].Lstd[j]=raw->obs.data[n].Pstd[j]=0.0;
+            raw->obs.data[n].LLI[j]=0;
             raw->obs.data[n].code[j]=CODE_NONE;
         }
         n++;
@@ -429,9 +429,6 @@ static int decode_rxmrawx(raw_t *raw)
         cn0  =U1(p+26);    /* cn0 (dBHz) */
         prstd=U1(p+27)&15; /* pseudorange std-dev: (0.01*2^n meters) */
         cpstd=U1(p+28)&15; /* cpStdev (n*0.004 m) */
-        /* subtract offset to use valid rinex format range (0->9) */
-        prstd=prstd>=5?prstd-5:0; /* prstd=0.01*2^(x-5) meters*/
-
         tstat=U1(p+30);    /* trkStat */
         if (!(tstat&1)) P=0.0;
         if (!(tstat&2)||L==-0.5||cpstd>cpstd_valid) L=0.0; /* invalid phase */
@@ -504,19 +501,19 @@ static int decode_rxmrawx(raw_t *raw)
             raw->obs.data[n].rcv=0;
             for (k=0;k<NFREQ+NEXOBS;k++) {
                 raw->obs.data[n].L[k]=raw->obs.data[n].P[k]=0.0;
-                raw->obs.data[n].Lstd[k]=raw->obs.data[n].Pstd[k]=0;
-                raw->obs.data[n].D[k]=0.0;
-                raw->obs.data[n].SNR[k]=raw->obs.data[n].LLI[k]=0;
+                raw->obs.data[n].D[k]=raw->obs.data[n].SNR[k]=0.0;
+                raw->obs.data[n].Lstd[k]=raw->obs.data[n].Pstd[k]=0.0;
+                raw->obs.data[n].LLI[k]=0;
                 raw->obs.data[n].code[k]=CODE_NONE;
             }
             n++;
         }
         raw->obs.data[j].L[idx]=L;
         raw->obs.data[j].P[idx]=P;
-        raw->obs.data[j].Lstd[idx]=rcvstds?cpstd:0;
-        raw->obs.data[j].Pstd[idx]=rcvstds?prstd:0;
+        raw->obs.data[j].Lstd[idx] = rcvstds ? cpstd * 0.004 : 0;
+        raw->obs.data[j].Pstd[idx] = rcvstds ? 0.01 * pow(2, prstd) : 0.0;
         raw->obs.data[j].D[idx]=(float)D;
-        raw->obs.data[j].SNR[idx]=(uint16_t)(cn0*1.0/SNR_UNIT+0.5);
+        raw->obs.data[j].SNR[idx]=cn0;
         raw->obs.data[j].LLI[idx]=(uint8_t)LLI;
         raw->obs.data[j].code[idx]=(uint8_t)code;
         if (L!=0.0) raw->lockflag[sat-1][idx]=0; /* clear slip carry-forward flag if valid phase*/
@@ -612,6 +609,9 @@ static int decode_trkmeas(raw_t *raw)
     time=gpst2time(week,tr);
     
     utc_gpst=timediff(gpst2utc(time),time);
+
+    int rcvstds = 0;
+    if (strstr(raw->opt,"-RCVSTDS")) rcvstds=1;
     
     for (i=0,p=raw->buff+110;i<nch;i++,p+=56) {
         
@@ -670,9 +670,9 @@ static int decode_trkmeas(raw_t *raw)
         raw->obs.data[n].P[0]=tau*CLIGHT;
         raw->obs.data[n].L[0]=-adr;
         raw->obs.data[n].D[0]=(float)dop;
-        raw->obs.data[n].SNR[0]=(uint16_t)(snr/SNR_UNIT+0.5);
+        raw->obs.data[n].SNR[0]=snr;
         raw->obs.data[n].code[0]=sys==SYS_CMP?CODE_L2I:CODE_L1C;
-        raw->obs.data[n].Lstd[0]=8-qi;
+        raw->obs.data[n].Lstd[0] = rcvstds ? (8 - qi) * 0.004 : 0;
         raw->obs.data[n].LLI[0]=raw->lockt[sat-1][1]>0.0?1:0;
         if (sys==SYS_SBS) { /* half-cycle valid */
             raw->obs.data[n].LLI[0]|=lock2>142?0:2;
@@ -688,9 +688,9 @@ static int decode_trkmeas(raw_t *raw)
         }
         for (j=1;j<NFREQ+NEXOBS;j++) {
             raw->obs.data[n].L[j]=raw->obs.data[n].P[j]=0.0;
-            raw->obs.data[n].D[j]=0.0;
-            raw->obs.data[n].SNR[j]=raw->obs.data[n].LLI[j]=0;
-            raw->obs.data[n].Lstd[j]=raw->obs.data[n].Pstd[j]=0;
+            raw->obs.data[n].D[j]=raw->obs.data[n].SNR[j]=0.0;
+            raw->obs.data[n].Lstd[j]=raw->obs.data[n].Pstd[j]=0.0;
+            raw->obs.data[n].LLI[j]=0;
             raw->obs.data[n].code[j]=CODE_NONE;
         }
         n++;
@@ -796,15 +796,15 @@ static int decode_trkd5(raw_t *raw)
         raw->obs.data[n].P[0]=tau*CLIGHT;
         raw->obs.data[n].L[0]=-adr;
         raw->obs.data[n].D[0]=(float)dop;
-        raw->obs.data[n].SNR[0]=(uint16_t)(snr/SNR_UNIT+0.5);
+        raw->obs.data[n].SNR[0]=snr;
         raw->obs.data[n].code[0]=sys==SYS_CMP?CODE_L2I:CODE_L1C;
         raw->obs.data[n].LLI[0]=raw->lockt[sat-1][1]>0.0?1:0;
         raw->lockt[sat-1][1]=0.0;
         
         for (j=1;j<NFREQ+NEXOBS;j++) {
             raw->obs.data[n].L[j]=raw->obs.data[n].P[j]=0.0;
-            raw->obs.data[n].D[j]=0.0;
-            raw->obs.data[n].SNR[j]=raw->obs.data[n].LLI[j]=0;
+            raw->obs.data[n].D[j]=raw->obs.data[n].SNR[j]=0.0;
+            raw->obs.data[n].LLI[j]=0;
             raw->obs.data[n].code[j]=CODE_NONE;
         }
         n++;
diff --git a/src/rcv/unicore.c b/src/rcv/unicore.c
index 5d7f6d1d4..e7b519f7b 100644
--- a/src/rcv/unicore.c
+++ b/src/rcv/unicore.c
@@ -77,8 +77,9 @@ static int obsindex(obs_t* obs, gtime_t time, int sat)
     obs->data[i].sat = sat;
     for (j = 0; j < NFREQ + NEXOBS; j++) {
         obs->data[i].L[j] = obs->data[i].P[j] = 0.0;
-        obs->data[i].D[j] = 0.0;
-        obs->data[i].SNR[j] = obs->data[i].LLI[j] = 0;
+        obs->data[i].D[j] = obs->data[i].SNR[j] = 0.0;
+        obs->data[i].Lstd[j] = obs->data[i].Pstd[j] = 0.0;
+        obs->data[i].LLI[j] = 0;
         obs->data[i].code[j] = CODE_NONE;
     }
     obs->n++;
@@ -804,25 +805,14 @@ static int decode_obsvmb(raw_t* raw)
             raw->obs.data[index].L[idx] = -adr;
             raw->obs.data[index].P[idx] = psr;
             raw->obs.data[index].D[idx] = (float)dop;
-            raw->obs.data[index].SNR[idx] = (uint16_t)(snr / SNR_UNIT + 0.5);
+            raw->obs.data[index].SNR[idx] = snr;
             raw->obs.data[index].LLI[idx] = (uint8_t)lli;
             raw->obs.data[index].code[idx] = (uint8_t)code;
             if (rcvstds) {
                 double pstd = U2(p + 20) * 0.01;  // Meters
-                // To RTKlib encoding
-                pstd = log2(pstd / 0.01) - 5;
-                pstd = pstd > 0 ? pstd : 0;
-                // Further limited to 9 in RINEX output
-                pstd = pstd <= 254 ? pstd : 254;
-                raw->obs.data[index].Pstd[idx] = pstd + 0.5;
-
+                raw->obs.data[index].Pstd[idx] = pstd;
                 double lstd = U2(p + 22) * 0.0001; // Cycles
-                // To RTKlib encoding
-                lstd = lstd / 0.004;
-                lstd = lstd > 0 ? lstd : 0;
-                // Further limited to 9 in RINEX output
-                lstd = lstd <= 254 ? lstd : 254;
-                raw->obs.data[index].Lstd[idx] = lstd + 0.5;
+                raw->obs.data[index].Lstd[idx] = lstd;
             }
         }
     }
diff --git a/src/rinex.c b/src/rinex.c
index 398aa8f0a..c55591d9e 100644
--- a/src/rinex.c
+++ b/src/rinex.c
@@ -780,7 +780,7 @@ static int decode_obsdata(FILE *fp, char *buff, double ver, int mask,
     sigind_t *ind;
     double val[MAXOBSTYPE]={0};
     uint8_t lli[MAXOBSTYPE]={0};
-    uint8_t std[MAXOBSTYPE]={0};
+    double std[MAXOBSTYPE]={0};
     char satid[8]="";
     int i,j,n,m,q,stat=1,p[MAXOBSTYPE],k[16],l[16],r[16];
 
@@ -816,15 +816,17 @@ static int decode_obsdata(FILE *fp, char *buff, double ver, int mask,
         if (stat) {
             val[i]=str2num(buff,j,14)+ind->shift[i];
             lli[i]=(uint8_t)str2num(buff,j+14,1)&3;
-            /* measurement std from receiver */
-            std[i]=(uint8_t)str2num(buff,j+15,1);
+            /* measurement std from receiver, encoded */
+            std[i]=str2num(buff,j+15,1);
         }
     }
     if (!stat) return 0;
 
     for (i=0;i<NFREQ+NEXOBS;i++) {
-        obs->P[i]=obs->L[i]=0.0; obs->D[i]=0.0f;
-        obs->SNR[i]=obs->LLI[i]=obs->Lstd[i]=obs->Pstd[i]=obs->code[i]=0;
+        obs->P[i]=obs->L[i]=0.0;
+        obs->D[i]=obs->SNR[i]=0.0;
+        obs->Lstd[i]=obs->Pstd[i]=0.0;
+        obs->LLI[i]=obs->code[i]=0;
     }
     /* assign position in observation data */
     for (i=n=m=q=0;i<ind->n;i++) {
@@ -897,14 +899,14 @@ static int decode_obsdata(FILE *fp, char *buff, double ver, int mask,
         switch (ind->type[i]) {
             case 0: obs->P[p[i]]=val[i];
                     obs->code[p[i]]=ind->code[i];
-                    obs->Pstd[p[i]]=std[i]>0?std[i]:0;
+                    obs->Pstd[p[i]] = std[i] > 0 ? 0.01 * pow(2, std[i] + 5) : 0;
                     break;
             case 1: obs->L[p[i]]=val[i];
                     obs->LLI[p[i]]=lli[i];
-                    obs->Lstd[p[i]]=std[i]>0?std[i]:0;
+                    obs->Lstd[p[i]] = std[i] > 0 ? std[i] * 0.004 : 0;
                     break;
-            case 2: obs->D[p[i]]=(float)val[i];                     break;
-            case 3: obs->SNR[p[i]]=(uint16_t)(val[i]/SNR_UNIT+0.5); break;
+            case 2: obs->D[p[i]]=(float)val[i]; break;
+            case 3: obs->SNR[p[i]]=val[i]; break;
         }
         trace(4, "obs: i=%d f=%d P=%14.3f L=%14.3f LLI=%d code=%d\n",i,p[i],obs->P[p[i]],
         obs->L[p[i]],obs->LLI[p[i]],obs->code[p[i]]);
@@ -2433,22 +2435,32 @@ extern int outrnxobsb(FILE *fp, const rnxopt_t *opt, const obsd_t *obs, int n,
             /* output field */
             switch (opt->tobs[m][j][0]) {
                 case 'C':
-                case 'P': outrnxobsf(fp,obs[ind[i]].P[k],-1,obs[ind[i]].Pstd[k]); break;
-                case 'L': outrnxobsf(fp,obs[ind[i]].L[k]+dL,obs[ind[i]].LLI[k],obs[ind[i]].Lstd[k]); break;
+                case 'P': {
+                  // To RTKLib RINEX encoding
+                  int pstdi = log2(obs[ind[i]].Pstd[k] * 100) - 5 + 0.5;
+                  outrnxobsf(fp,obs[ind[i]].P[k],-1,pstdi);
+                  break;
+                }
+                case 'L': {
+                  // To RTKLib RINEX encoding
+                  int lstdi = obs[ind[i]].Lstd[k] / 0.004 + 0.5;
+                  outrnxobsf(fp,obs[ind[i]].L[k]+dL,obs[ind[i]].LLI[k],lstdi);
+                  break;
+                }
                 case 'D': outrnxobsf(fp,obs[ind[i]].D[k],-1,-1); break;
-                case 'S': outrnxobsf(fp,obs[ind[i]].SNR[k]*SNR_UNIT,-1,-1); break;
+                case 'S': outrnxobsf(fp,obs[ind[i]].SNR[k],-1,-1); break;
             }
         }
 
         /* set trace level to 1 generate CSV file of raw observations   */
 #ifdef TRACE
         if (gettracelevel()==1) {
-            trace(1,",%16.2f,%3d,%13.2f,%13.2f,%9.2f,%2.0f,%1d,%1d,%13.2f,%13.2f,%9.2f,%2.0f,%1d,%1d\n",
+            trace(1,",%16.2f,%3d,%13.2f,%13.2f,%9.2f,%2.0f,%1d,%3.4f,%13.2f,%13.2f,%9.2f,%2.0f,%1d,%3.4f\n",
                 obs[0].time.time + obs[0].time.sec, obs[ind[i]].sat,
                 obs[ind[i]].P[0], obs[ind[i]].L[0], obs[ind[i]].D[0],
-                obs[ind[i]].SNR[0]*SNR_UNIT, obs[ind[i]].LLI[0], obs[ind[i]].Lstd[0],
+                obs[ind[i]].SNR[0], obs[ind[i]].LLI[0], obs[ind[i]].Lstd[0],
                 obs[ind[i]].P[1], obs[ind[i]].L[1], obs[ind[i]].D[1],
-                obs[ind[i]].SNR[1]*SNR_UNIT, obs[ind[i]].LLI[1], obs[ind[i]].Lstd[1]);
+                obs[ind[i]].SNR[1], obs[ind[i]].LLI[1], obs[ind[i]].Lstd[1]);
         }
 #endif
 
diff --git a/src/rtcm2.c b/src/rtcm2.c
index cac2465cf..3768eed07 100644
--- a/src/rtcm2.c
+++ b/src/rtcm2.c
@@ -42,8 +42,8 @@ static int obsindex(obs_t *obs, gtime_t time, int sat)
     obs->data[i].sat=sat;
     for (j=0;j<NFREQ;j++) {
         obs->data[i].L[j]=obs->data[i].P[j]=0.0;
-        obs->data[i].D[j]=0.0;
-        obs->data[i].SNR[j]=obs->data[i].LLI[j]=obs->data[i].code[j]=0;
+        obs->data[i].D[j]=obs->data[i].SNR[j]=0.0;
+        obs->data[i].LLI[j]=obs->data[i].code[j]=0;
     }
     obs->n++;
     return i;
diff --git a/src/rtcm3.c b/src/rtcm3.c
index 649e6e2f7..e9e97e0e0 100644
--- a/src/rtcm3.c
+++ b/src/rtcm3.c
@@ -215,9 +215,9 @@ static int lossoflock(rtcm_t *rtcm, int sat, int idx, int lock)
     return lli;
 }
 /* S/N ratio -----------------------------------------------------------------*/
-static uint16_t snratio(double snr)
+static double snratio(double snr)
 {
-    return (uint16_t)(snr<=0.0||100.0<=snr?0.0:snr/SNR_UNIT+0.5);
+    return snr<=0.0||100.0<=snr?0.0:snr;
 }
 /* get observation data index ------------------------------------------------*/
 static int obsindex(obs_t *obs, gtime_t time, int sat)
@@ -2091,7 +2091,7 @@ static void save_msm_obs(rtcm_t *rtcm, int sys, msm_h_t *h, const double *r,
                 }
                 rtcm->obs.data[index].LLI[idx[k]]=
                     lossoflock(rtcm,sat,idx[k],lock[j])+(half[j]?2:0);
-                rtcm->obs.data[index].SNR [idx[k]]=(uint16_t)(cnr[j]/SNR_UNIT+0.5);
+                rtcm->obs.data[index].SNR [idx[k]]=cnr[j];
                 rtcm->obs.data[index].code[idx[k]]=code[k];
             }
             j++;
diff --git a/src/rtcm3e.c b/src/rtcm3e.c
index 2a7eb01eb..127f44c5d 100644
--- a/src/rtcm3e.c
+++ b/src/rtcm3e.c
@@ -281,8 +281,8 @@ static void gen_obs_gps(rtcm_t *rtcm, const obsd_t *data, int *code1, int *pr1,
     
     if (lock1) *lock1=to_lock(lt1);
     if (lock2) *lock2=to_lock(lt2);
-    if (cnr1 ) *cnr1=ROUND(data->SNR[0]*SNR_UNIT/0.25);
-    if (cnr2 ) *cnr2=ROUND(data->SNR[1]*SNR_UNIT/0.25);
+    if (cnr1 ) *cnr1=ROUND(data->SNR[0]/0.25);
+    if (cnr2 ) *cnr2=ROUND(data->SNR[1]/0.25);
     if (code1) *code1=to_code1_gps(data->code[0]);
     if (code2) *code2=to_code2_gps(data->code[1]);
 }
@@ -330,8 +330,8 @@ static void gen_obs_glo(rtcm_t *rtcm, const obsd_t *data, int fcn, int *code1,
     
     if (lock1) *lock1=to_lock(lt1);
     if (lock2) *lock2=to_lock(lt2);
-    if (cnr1 ) *cnr1=ROUND(data->SNR[0]*SNR_UNIT/0.25);
-    if (cnr2 ) *cnr2=ROUND(data->SNR[1]*SNR_UNIT/0.25);
+    if (cnr1 ) *cnr1=ROUND(data->SNR[0]/0.25);
+    if (cnr2 ) *cnr2=ROUND(data->SNR[1]/0.25);
     if (code1) *code1=to_code1_glo(data->code[0]);
     if (code2) *code2=to_code2_glo(data->code[1]);
 }
@@ -2039,7 +2039,7 @@ static void gen_msm_sig(rtcm_t *rtcm, int sys, int nsat, int nsig, int ncell,
             if (rate &&rate_s !=0.0) rate [cell-1]=rate_s;
             if (lock) lock[cell-1]=lt;
             if (half) half[cell-1]=(data->LLI[j]&2)?1:0;
-            if (cnr ) cnr [cell-1]=(float)(data->SNR[j]*SNR_UNIT);
+            if (cnr ) cnr [cell-1]=data->SNR[j];
         }
     }
 }
diff --git a/src/rtklib.h b/src/rtklib.h
index 4c727a045..5ae9813cc 100644
--- a/src/rtklib.h
+++ b/src/rtklib.h
@@ -145,8 +145,6 @@ extern "C" {
 #define NEXOBS      0                   /* number of extended obs codes */
 #endif
 
-#define SNR_UNIT    0.001               /* SNR unit (dBHz) */
-
 #define MINPRNGPS   1                   /* min satellite PRN number of GPS */
 #define MAXPRNGPS   32                  /* max satellite PRN number of GPS */
 #define NSATGPS     (MAXPRNGPS-MINPRNGPS+1) /* number of GPS satellites */
@@ -566,19 +564,18 @@ typedef struct {        /* time struct */
 typedef struct {        /* observation data record */
     gtime_t time;       /* receiver sampling time (GPST) */
     uint8_t sat,rcv;    /* satellite/receiver number */
-    uint16_t SNR[NFREQ+NEXOBS]; /* signal strength (0.001 dBHz) */
-    uint8_t  LLI[NFREQ+NEXOBS]; /* loss of lock indicator */
+    uint8_t freq;       /* GLONASS frequency channel (0-13) */
+    uint8_t LLI[NFREQ+NEXOBS]; /* loss of lock indicator */
     uint8_t code[NFREQ+NEXOBS]; /* code indicator (CODE_???) */
     double L[NFREQ+NEXOBS]; /* observation data carrier-phase (cycle) */
     double P[NFREQ+NEXOBS]; /* observation data pseudorange (m) */
-    float  D[NFREQ+NEXOBS]; /* observation data doppler frequency (Hz) */
+    float D[NFREQ+NEXOBS]; /* observation data doppler frequency (Hz) */
+    float SNR[NFREQ+NEXOBS]; /* signal strength (dBHz) */
+    float Lstd[NFREQ+NEXOBS]; /* stdev of carrier phase (cycles)  */
+    float Pstd[NFREQ+NEXOBS]; /* stdev of pseudorange (meters) */
 
     int timevalid;      /* time is valid (Valid GNSS fix) for time mark */
     gtime_t eventime;   /* time of event (GPST) */
-    uint8_t Lstd[NFREQ+NEXOBS]; /* stdev of carrier phase (0.004 cycles)  */
-    uint8_t Pstd[NFREQ+NEXOBS]; /* stdev of pseudorange (0.01*2^(n+5) meters) */
-    uint8_t freq; /* GLONASS frequency channel (0-13) */
-
 } obsd_t;
 
 typedef struct {        /* observation data */
@@ -924,7 +921,7 @@ typedef struct {        /* solution status type */
     float resp;         /* pseudorange residual (m) */
     float resc;         /* carrier-phase residual (m) */
     uint8_t flag;       /* flags: (vsat<<5)+(slip<<3)+fix */
-    uint16_t snr;       /* signal strength (*SNR_UNIT dBHz) */
+    float snr;          /* signal strength (dBHz) */
     uint16_t lock;      /* lock counter */
     uint16_t outc;      /* outage counter */
     uint16_t slipc;     /* slip counter */
@@ -1158,8 +1155,8 @@ typedef struct {        /* satellite status type */
     double resc[NFREQ]; /* residuals of carrier-phase (m) */
     double icbias[NFREQ];  /* glonass IC bias (cycles) */
     uint8_t vsat[NFREQ]; /* valid satellite flag */
-    uint16_t snr_rover [NFREQ]; /* rover signal strength (0.25 dBHz) */
-    uint16_t snr_base  [NFREQ]; /* base signal strength (0.25 dBHz) */
+    float snr_rover [NFREQ]; /* rover signal strength (dBHz) */
+    float snr_base  [NFREQ]; /* base signal strength (dBHz) */
     uint8_t fix [NFREQ]; /* ambiguity fix flag (1:float,2:fix,3:hold) */
     uint8_t slip[NFREQ]; /* cycle-slip flag */
     uint8_t half[NFREQ]; /* half-cycle valid flag */
diff --git a/src/rtkpos.c b/src/rtkpos.c
index cdc26506a..0ee43fc22 100644
--- a/src/rtkpos.c
+++ b/src/rtkpos.c
@@ -313,7 +313,7 @@ extern int rtkoutstat(rtk_t *rtk, int level, char *buff)
             int k=IB(i+1,j,&rtk->opt);
             p+=sprintf(p,"$SAT,%d,%.3f,%s,%d,%.1f,%.1f,%.4f,%.4f,%d,%.0f,%d,%d,%d,%u,%u,%u,%.2f,%.6f,%.5f\n",
                        week,tow,id,j+1,ssat->azel[0]*R2D,ssat->azel[1]*R2D,
-                       ssat->resp[j],ssat->resc[j],ssat->vsat[j],ssat->snr_rover[j]*SNR_UNIT,
+                       ssat->resp[j],ssat->resc[j],ssat->vsat[j],ssat->snr_rover[j],
                        ssat->fix[j],ssat->slip[j]&3,ssat->lock[j],ssat->outc[j],
                        ssat->slipc[j],ssat->rejc[j],k<rtk->nx?rtk->x[k]:0,
                        k<rtk->nx?rtk->P[k+k*rtk->nx]:0,ssat->icbias[j]);
@@ -437,8 +437,8 @@ static double varerr(int sat, int sys, double el, double snr_rover, double snr_b
                   pow(10,0.1*MAX(snr_max-snr_base, 0)));
     }
     if (opt->err[7]>0.0) {   /* add rcvr stdevs term */
-        if (code) var+=SQR(opt->err[7]*0.01*(1<<(obs->Pstd[frq]+5))); /* 0.01*2^(n+5) */
-        else var+=SQR(opt->err[7]*obs->Lstd[frq]*0.004*0.2); /* 0.004 cycles -> m) */
+        if (code) var+=SQR(opt->err[7]*obs->Pstd[frq]);
+        else var+=SQR(opt->err[7]*obs->Lstd[frq]*0.2);
     }
 
     var*=(opt->ionoopt==IONOOPT_IFLC)?SQR(3.0):1.0;
@@ -942,8 +942,8 @@ static void zdres_sat(int base, double r, const obsd_t *obs, const nav_t *nav,
 
         if (freq1==0.0||freq2==0.0) return;
 
-        if (testsnr(base,0,azel[1],obs->SNR[0]*SNR_UNIT,&opt->snrmask)||
-            testsnr(base,f2,azel[1],obs->SNR[f2]*SNR_UNIT,&opt->snrmask)) return;
+        if (testsnr(base,0,azel[1],obs->SNR[0],&opt->snrmask)||
+            testsnr(base,f2,azel[1],obs->SNR[f2],&opt->snrmask)) return;
 
         C1= SQR(freq1)/(SQR(freq1)-SQR(freq2));
         C2=-SQR(freq2)/(SQR(freq1)-SQR(freq2));
@@ -962,7 +962,7 @@ static void zdres_sat(int base, double r, const obsd_t *obs, const nav_t *nav,
             if ((freq[i]=sat2freq(obs->sat,obs->code[i],nav))==0.0) continue;
 
             /* check SNR mask */
-            if (testsnr(base,i,azel[1],obs->SNR[i]*SNR_UNIT,&opt->snrmask)) {
+            if (testsnr(base,i,azel[1],obs->SNR[i],&opt->snrmask)) {
                 continue;
             }
             /* residuals = observable - estimated range */
@@ -1345,12 +1345,12 @@ static int ddres(rtk_t *rtk, const obsd_t *obs, double dt, const double *x,
 
                 /* single-differenced measurement error variances (m) */
                 Ri[nv] = varerr(sat[i], sysi, azel[1+iu[i]*2],
-                                SNR_UNIT*rtk->ssat[sat[i]-1].snr_rover[frq],
-                                SNR_UNIT*rtk->ssat[sat[i]-1].snr_base[frq],
+                                rtk->ssat[sat[i]-1].snr_rover[frq],
+                                rtk->ssat[sat[i]-1].snr_base[frq],
                                 bl,dt,f,opt,&obs[iu[i]]);
                 Rj[nv] = varerr(sat[j], sysj, azel[1+iu[j]*2],
-                                SNR_UNIT*rtk->ssat[sat[j]-1].snr_rover[frq],
-                                SNR_UNIT*rtk->ssat[sat[j]-1].snr_base[frq],
+                                rtk->ssat[sat[j]-1].snr_rover[frq],
+                                rtk->ssat[sat[j]-1].snr_base[frq],
                                 bl,dt,f,opt,&obs[iu[j]]);
                 /* increase variance if half cycle flags set */
                 if (!code&&(obs[iu[i]].LLI[frq]&LLI_HALFC)) Ri[nv]+=0.01;
diff --git a/src/rtksvr.c b/src/rtksvr.c
index 27421ee60..73adb00b4 100644
--- a/src/rtksvr.c
+++ b/src/rtksvr.c
@@ -1082,7 +1082,7 @@ extern int rtksvrostat(rtksvr_t *svr, int rcv, gtime_t *time, int *sat,
         az  [i]=svr->rtk.ssat[sat[i]-1].azel[0];
         el  [i]=svr->rtk.ssat[sat[i]-1].azel[1];
         for (j=0;j<NFREQ;j++) {
-            snr[i][j]=(int)(svr->obs[rcv][0].data[i].SNR[j]*SNR_UNIT+0.5);
+            snr[i][j]=(int)(svr->obs[rcv][0].data[i].SNR[j]+0.5);
         }
         if (svr->rtk.sol.stat==SOLQ_NONE||svr->rtk.sol.stat==SOLQ_SINGLE) {
             vsat[i]=svr->rtk.ssat[sat[i]-1].vs;
diff --git a/src/solution.c b/src/solution.c
index fd37f3f11..6f9a0e1e9 100644
--- a/src/solution.c
+++ b/src/solution.c
@@ -1079,7 +1079,7 @@ static int decode_solstat(char *buff, solstat_t *stat)
     stat->resp =(float)resp;
     stat->resc =(float)resc;
     stat->flag =(uint8_t)((vsat<<5)+(slip<<3)+fix);
-    stat->snr  =(uint16_t)(snr/SNR_UNIT+0.5);
+    stat->snr  =(float)snr;
     stat->lock =(uint16_t)lock;
     stat->outc =(uint16_t)outc;
     stat->slipc=(uint16_t)slipc;
@@ -1424,7 +1424,7 @@ extern int outnmea_gsv(uint8_t *buff, const sol_t *sol, const ssat_t *ssat)
                     else if (sys==SYS_QZS) prn-=192; /* QZS: 01-10 */
                     az =ssat[sats[n]-1].azel[0]*R2D; if (az<0.0) az+=360.0;
                     el =ssat[sats[n]-1].azel[1]*R2D;
-                    snr=ssat[sats[n]-1].snr_rover[0]*SNR_UNIT;
+                    snr=ssat[sats[n]-1].snr_rover[0];
                 p+=sprintf(p,",%02d,%02.0f,%03.0f,%02.0f",prn,el,az,snr);
             }
             else p+=sprintf(p,",,,,");
diff --git a/src/trace.c b/src/trace.c
index c2bcea080..664b2ccad 100644
--- a/src/trace.c
+++ b/src/trace.c
@@ -102,11 +102,11 @@ extern void traceobs_impl(int level, const obsd_t *obs, int n)
         satno2id(obs[i].sat, id);
         fprintf(fp_trace,
                 " (%2d) %s %-3s rcv%d %13.3f %13.3f %13.3f %13.3f %d %d %d %d "
-                "%x %x %3.1f %3.1f\n",
+                "%3.4f %3.3f %3.1f %3.1f\n",
                 i + 1, str, id, obs[i].rcv, obs[i].L[0], obs[i].L[1],
                 obs[i].P[0], obs[i].P[1], obs[i].LLI[0], obs[i].LLI[1],
                 obs[i].code[0], obs[i].code[1], obs[i].Lstd[0], obs[i].Pstd[0],
-                obs[i].SNR[0] * SNR_UNIT, obs[i].SNR[1] * SNR_UNIT);
+                obs[i].SNR[0], obs[i].SNR[1]);
     }
     fflush(fp_trace);
 }
diff --git a/util/simobs/simobs.c b/util/simobs/simobs.c
index 30f1871ab..77f33c232 100644
--- a/util/simobs/simobs.c
+++ b/util/simobs/simobs.c
@@ -281,7 +281,7 @@ static int simobs(simopt_t simopt, rnxopt_t rnxopt, nav_t *nav, obs_t *obs) {
 
         data[j].L[m]   = cp/CLIGHT*fk;
         data[j].P[m]   = pr;
-        data[j].SNR[m] = (uint16_t)(snr/SNR_UNIT + 0.5);
+        data[j].SNR[m] = snr;
         data[j].LLI[m] = 0; /* (data[j].SNR[m]<slipthres? 1 : 0); */
 
         m++;