diff options
Diffstat (limited to 'gr-fec/lib/viterbi/viterbi.h')
-rw-r--r-- | gr-fec/lib/viterbi/viterbi.h | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/gr-fec/lib/viterbi/viterbi.h b/gr-fec/lib/viterbi/viterbi.h new file mode 100644 index 0000000000..97e09d4a8d --- /dev/null +++ b/gr-fec/lib/viterbi/viterbi.h @@ -0,0 +1,53 @@ +/* + * Copyright 2008 Free Software Foundation, Inc. + * + * This file is part of GNU Radio + * + * GNU Radio is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 3, or (at your option) + * any later version. + * + * GNU Radio is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with GNU Radio; see the file COPYING. If not, write to + * the Free Software Foundation, Inc., 51 Franklin Street, + * Boston, MA 02110-1301, USA. + */ + +/* The path memory for each state is 32 bits. This is slightly shorter + * than we'd like for K=7, especially since we chain back every 8 bits. + * But it fits so nicely into a 32-bit machine word... + */ + +#include <fec/api.h> + +struct viterbi_state { + unsigned long path; /* Decoded path to this state */ + long metric; /* Cumulative metric to this state */ +}; + +FEC_API +int gen_met(int mettab[2][256], /* Metric table */ + int amp, /* Signal amplitude */ + double esn0, /* Es/N0 ratio in dB */ + double bias, /* Metric bias */ + int scale); /* Scale factor */ + +FEC_API unsigned char +encode(unsigned char *symbols, unsigned char *data, + unsigned int nbytes,unsigned char encstate); + +FEC_API void +viterbi_chunks_init(struct viterbi_state* state); + + FEC_API void +viterbi_butterfly2(unsigned char *symbols, int mettab[2][256], + struct viterbi_state *state0, struct viterbi_state *state1); + +FEC_API unsigned char +viterbi_get_output(struct viterbi_state *state, unsigned char *outbuf); |