rtkplot/rtkplot_qt: calculate multipath even if either L1 or L2 is not

available

Author: JensReimann

app/qtapp/rtkplot_qt/plotdata.cpp

@@ -1284,10 +1284,19 @@ void Plot::updateMp()
 
     for (i = 0; i < observation.n; i++) {
         data = observation.data + i;
-        freq1 = sat2freq(data->sat, data->code[0], &navigation);
-        freq2 = sat2freq(data->sat, data->code[1], &navigation);
-        if (data->L[0] == 0.0 || data->L[1] == 0.0 || freq1 == 0.0 || freq2 == 0.0) continue;
-        I = -CLIGHT * (data->L[0] / freq1-data->L[1] / freq2) / (1.0 - SQR(freq1 / freq2));
+        /* choose two frequencies to calculate reference I */
+        for (j = 0; j < NFREQ + NEXOBS; j++) {
+            freq1 = sat2freq(data->sat, data->code[j], &navigation);
+            if (data->L[j] == 0.0 || freq1 == 0.0 ) continue;
+            for (k = j + 1; k < NFREQ + NEXOBS; k++) {
+                freq2 = sat2freq(data->sat, data->code[k], &navigation);
+                if (data->L[k] == 0.0 || freq2 == 0.0 || freq1 == freq2) continue;
+                I = -CLIGHT * (data->L[j] / freq1-data->L[k] / freq2) / (1.0 - SQR(freq1 / freq2));
+                break;
+            }
+            break;
+        }
+        if (freq1 == 0.0 || freq2 == 0.0) continue;
 
         for (j = 0; j < NFREQ + NEXOBS; j++) {
             freq = sat2freq(data->sat, data->code[j], &navigation);

app/winapp/rtkplot/plotdata.cpp

@@ -1297,11 +1297,20 @@ void __fastcall TPlot::UpdateMp(void)
 
     for (i=0;i<Obs.n;i++) {
         data=Obs.data+i;
-        freq1=sat2freq(data->sat,data->code[0],&Nav);
-        freq2=sat2freq(data->sat,data->code[1],&Nav);
-        if (data->L[0]==0.0||data->L[1]==0.0||freq1==0.0||freq2==0.0) continue;
-        I=-CLIGHT*(data->L[0]/freq1-data->L[1]/freq2)/(1.0-SQR(freq1/freq2));
-        
+	/* choose two frequencies to calculate reference I */
+        for (j = 0; j < NFREQ + NEXOBS; j++) {
+            freq1 = sat2freq(data->sat, data->code[j], &Nav);
+            if (data->L[j] == 0.0 || freq1 == 0.0 ) continue;
+            for (k = j + 1; k < NFREQ + NEXOBS; k++) {
+                freq2 = sat2freq(data->sat, data->code[k], &Nav);
+                if (data->L[k] == 0.0 || freq2 == 0.0 || freq1 == freq2) continue;
+                I = -CLIGHT * (data->L[j] / freq1-data->L[k] / freq2) / (1.0 - SQR(freq1 / freq2));
+                break;
+            }
+            break;
+        }
+        if (freq1 == 0.0 || freq2 == 0.0) continue;
+
         for (j=0;j<NFREQ+NEXOBS;j++) {
             freq=sat2freq(data->sat,data->code[j],&Nav);
             if (data->P[j]==0.0||data->L[j]==0.0||freq==0.0) continue;