Several enhancements to gr-trellis and gnuradio-examples/python/channel-coding:

-Added fsm constructor for generating FSM directly from the
generator matrix of binary convolutional codes.
-Added functionality to fsm class to compute the best way to
go from any state to any other state (useful for termination)
-Added soft-in-soft-out (SISO) block for turbo processing
-Added turbo decoding examples



git-svn-id: http://gnuradio.org/svn/gnuradio/trunk@3322 221aa14e-8319-0410-a670-987f0aec2ac5

1 files changed, 14 insertions, 16 deletions

diff --git a/gr-trellis/src/lib/trellis_encoder_bb.cc b/gr-trellis/src/lib/trellis_encoder_bb.cc
index aecba87a4..cad4490ad 100644
--- a/gr-trellis/src/lib/trellis_encoder_bb.cc
+++ b/gr-trellis/src/lib/trellis_encoder_bb.cc
@@ -29,12 +29,12 @@
 #include <iostream>
 
 trellis_encoder_bb_sptr 
-trellis_make_encoder_bb (const fsm &FSM, const int ST)
+trellis_make_encoder_bb (const fsm &FSM, int ST)
 {
   return trellis_encoder_bb_sptr (new trellis_encoder_bb (FSM,ST));
 }
 
-trellis_encoder_bb::trellis_encoder_bb (const fsm &FSM, const int ST)
+trellis_encoder_bb::trellis_encoder_bb (const fsm &FSM, int ST)
   : gr_sync_block ("encoder_bb",
 		   gr_make_io_signature (1, -1, sizeof (unsigned char)),
 		   gr_make_io_signature (1, -1, sizeof (unsigned char))),
@@ -50,26 +50,24 @@ trellis_encoder_bb::work (int noutput_items,
 			gr_vector_const_void_star &input_items,
 			gr_vector_void_star &output_items)
 {
-  int d_ST_tmp;
+  int ST_tmp;
 
   assert (input_items.size() == output_items.size());
   int nstreams = input_items.size();
 
-for (int m=0;m<nstreams;m++) {
-  const unsigned char *in = (const unsigned char *) input_items[m];
-  unsigned char *out = (unsigned char *) output_items[m];
-  d_ST_tmp = d_ST;
+  for (int m=0;m<nstreams;m++) {
+    const unsigned char *in = (const unsigned char *) input_items[m];
+    unsigned char *out = (unsigned char *) output_items[m];
+    ST_tmp = d_ST;
 
-// per stream processing
-
-  for (int i = 0; i < noutput_items; i++){
-    out[i] = (unsigned char) d_FSM.OS()[d_ST_tmp*d_FSM.I()+in[i]]; // direction of time?
-    d_ST_tmp = (int) d_FSM.NS()[d_ST_tmp*d_FSM.I()+in[i]];
+    // per stream processing
+    for (int i = 0; i < noutput_items; i++){
+      out[i] = (unsigned char) d_FSM.OS()[ST_tmp*d_FSM.I()+in[i]]; // direction of time?
+      ST_tmp = (int) d_FSM.NS()[ST_tmp*d_FSM.I()+in[i]];
+    }
+    // end per stream processing
   }
-
-// end per stream processing
-}
-  d_ST = d_ST_tmp;
+  d_ST = ST_tmp;
 
   return noutput_items;
 }