90 lines
2.7 KiB
C++
90 lines
2.7 KiB
C++
/*
|
|
* Copyright (C) 2016 Bastian Bloessl <bloessl@ccs-labs.org>
|
|
*
|
|
* This program 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 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
#ifndef INCLUDED_IEEE802_11_VITERBI_DECODER_H
|
|
#define INCLUDED_IEEE802_11_VITERBI_DECODER_H
|
|
|
|
#include <xmmintrin.h>
|
|
#include "utils.h"
|
|
|
|
namespace gr {
|
|
namespace ieee802_11 {
|
|
|
|
// Maximum number of traceback bytes
|
|
#define TRACEBACK_MAX 24
|
|
|
|
/* This Viterbi decoder was taken from the gr-dvbt module of
|
|
* GNU Radio. It is an SSE2 version of the Viterbi Decoder
|
|
* created by Phil Karn. The SSE2 version was made by Bogdan
|
|
* Diaconescu. For more info see: gr-dvbt/lib/d_viterbi.h
|
|
*/
|
|
class viterbi_decoder
|
|
{
|
|
public:
|
|
|
|
viterbi_decoder();
|
|
virtual ~viterbi_decoder();
|
|
|
|
uint8_t* decode(ofdm_param *ofdm, frame_param *frame, uint8_t *in);
|
|
|
|
private:
|
|
|
|
// Position in circular buffer where the current decoded byte is stored
|
|
int d_store_pos;
|
|
// Metrics for each state
|
|
unsigned char d_mmresult[64] __attribute__((aligned(16)));
|
|
// Paths for each state
|
|
unsigned char d_ppresult[TRACEBACK_MAX][64] __attribute__((aligned(16)));
|
|
|
|
|
|
union branchtab27 {
|
|
unsigned char c[32];
|
|
__m128i v[2];
|
|
} d_branchtab27_sse2[2];
|
|
|
|
__m128i d_metric0[4] __attribute__ ((aligned(16)));
|
|
__m128i d_metric1[4] __attribute__ ((aligned(16)));
|
|
__m128i d_path0[4] __attribute__ ((aligned(16)));
|
|
__m128i d_path1[4] __attribute__ ((aligned(16)));
|
|
|
|
int d_ntraceback;
|
|
int d_k;
|
|
ofdm_param *d_ofdm;
|
|
frame_param *d_frame;
|
|
const unsigned char *d_depuncture_pattern;
|
|
|
|
uint8_t d_depunctured[MAX_ENCODED_BITS];
|
|
uint8_t d_decoded[MAX_ENCODED_BITS * 3 / 4];
|
|
|
|
static const unsigned char PARTAB[256];
|
|
static const unsigned char PUNCTURE_1_2[2];
|
|
static const unsigned char PUNCTURE_2_3[4];
|
|
static const unsigned char PUNCTURE_3_4[6];
|
|
|
|
void reset();
|
|
uint8_t* depuncture(uint8_t *in);
|
|
void viterbi_chunks_init_sse2();
|
|
void viterbi_butterfly2_sse2(unsigned char *symbols,
|
|
__m128i m0[], __m128i m1[], __m128i p0[], __m128i p1[]);
|
|
unsigned char viterbi_get_output_sse2(__m128i *mm0,
|
|
__m128i *pp0, int ntraceback, unsigned char *outbuf);
|
|
};
|
|
|
|
} // namespace ieee802_11
|
|
} // namespace gr
|
|
|
|
#endif /* INCLUDED_IEEE802_11_VITERBI_DECODER_H */
|