Initial Commit

lib/encode232.f90

@@ -0,0 +1,33 @@
+subroutine encode232(dat,nsym,symbol)
+
+! Convolutional encoder for a K=32, r=1/2 code.
+
+  integer*1 dat(13)                 !User data, packed 8 bits per byte
+  integer*1 symbol(206)             !Channel symbols, one bit per byte
+  integer*1 i1
+  include 'conv232.f90'
+
+  nstate=0
+  k=0
+  do j=1,nsym
+     do i=7,0,-1
+        i1=dat(j)
+        i4=i1
+        if (i4.lt.0) i4=i4+256
+        nstate=ior(ishft(nstate,1),iand(ishft(i4,-i),1))
+        n=iand(nstate,npoly1)
+        n=ieor(n,ishft(n,-16))
+        k=k+1
+        symbol(k)=partab(iand(ieor(n,ishft(n,-8)),255))
+        n=iand(nstate,npoly2)
+        n=ieor(n,ishft(n,-16))
+        k=k+1
+        symbol(k)=partab(iand(ieor(n,ishft(n,-8)),255))
+        if(k.ge.nsym) go to 100
+     enddo
+  enddo
+
+100 continue
+
+  return
+end subroutine encode232