- fixed SBAS MT24,26 decoder.

Author: hirokawa

src/cssrlib/sbas.py

@@ -432,25 +432,16 @@ def decode_sbas_mask(self, msg, i):
         i += 2
         return i
 
-    def decode_sbas_fast_corr(self, msg, i):
-        """ Types 2 to 5 fast correction message """
-        type_ = 0 if self.msgtype == 0 else self.msgtype-2
-
-        iodf, iodp = bs.unpack_from('u2u2', msg, i)
-        i += 4
-
-        if iodp != self.iodp:
-            i += 208
-            return i
-
-        for k in range(13):
+    def decode_sbas_fast_corr_blk(self, msg, i, n, type_):
+        """ decode fast correction for n blocks """
+        for k in range(n):
             fc = bs.unpack_from('s12', msg, i)[0]
             i += 12
             j = type_*13+k
             if j >= len(self.sat):
                 break
             self.lc[0].hclk[self.sat[j]] = -self.sval(fc, 12, 0.125)
-        for k in range(13):
+        for k in range(n):
             udrei = bs.unpack_from('u4', msg, i)[0]
             i += 4
             j = type_*13+k
@@ -462,6 +453,20 @@ def decode_sbas_fast_corr(self, msg, i):
         self.lc[0].cstat |= (1 << sCType.HCLOCK)
         return i
 
+    def decode_sbas_fast_corr(self, msg, i):
+        """ Types 2 to 5 fast correction message """
+        type_ = 0 if self.msgtype == 0 else self.msgtype-2
+
+        iodf, iodp = bs.unpack_from('u2u2', msg, i)
+        i += 4
+
+        if iodp != self.iodp:
+            i += 208
+            return i
+
+        i = self.decode_sbas_fast_corr_blk(msg, i, 13, type_)
+        return i
+
     def decode_sbas_integrity(self, msg, i):
         """ Type 6 integrity message """
         iodf2, iodf3, iodf4, iodf5 = bs.unpack_from('u2u2u2u2', msg, i)
@@ -640,8 +645,8 @@ def decode_sbas_lcorr_half(self, msg, i):
         vc = bs.unpack_from('u1', msg, i)[0]
         i += 1
 
-        i0 = 117 if vc == 0 else 105
-        iodp = bs.unpack_from('u2', msg, i0)[0]
+        ofst = 102 if vc == 0 else 103
+        iodp = bs.unpack_from('u2', msg, i+ofst)[0]
         if iodp != self.iodp:
             return i
 
@@ -669,6 +674,20 @@ def decode_sbas_lcorr_half(self, msg, i):
 
         return i
 
+    def decode_sbas_mixed_corr(self, msg, i):
+        """ Type 24 mixed fast/long correction """
+
+        # fast correction (106bits)
+        iodp, type_, iodf = bs.unpack_from('u2u2u2', msg, i+96)
+
+        if iodp != self.iodp:
+            i += 208
+            return i
+
+        i = self.decode_sbas_fast_corr_blk(msg, i, 6, type_)
+        i = self.decode_sbas_lcorr_half(msg, i)  # MT25 half-msg(106bits)
+        return i
+
     def decode_sbas_long_corr(self, msg, i):
         """ Type 25 long-term satellite error correction """
         for k in range(2):
@@ -677,13 +696,18 @@ def decode_sbas_long_corr(self, msg, i):
 
     def decode_sbas_iono(self, msg, i):
         """ Type 26 Ionospheric delay message """
-        iodi = bs.unpack_from('u2', msg, 217)[0]
+        iodi = bs.unpack_from('u2', msg, i+203)[0]
         if iodi != self.iodi:
             i += 212
             return i
         band, bid = bs.unpack_from('u4u4', msg, i)
-        nigp = len(self.vtec[band])
         i += 8
+        if band not in self.vtec:
+            i += 204
+            return i
+
+        nigp = len(self.vtec[band])
+
         for k in range(15):
             vd, givei = bs.unpack_from('u9u4', msg, i)
             i += 13