rec_syst_conv_code.h

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// 
// SPUC - Signal processing using C++ - A DSP library
/*---------------------------------------------------------------------------*
 *                                   IT++                                    *
 *---------------------------------------------------------------------------*
 * Copyright (c) 1995-2001 by Tony Ottosson, Thomas Eriksson, Pål Frenger,   *
 * Tobias Ringström, and Jonas Samuelsson.                                   *
 *                                                                           *
 * Permission to use, copy, modify, and distribute this software and its     *
 * documentation under the terms of the GNU General Public License is hereby *
 * granted. No representations are made about the suitability of this        *
 * software for any purpose. It is provided "as is" without expressed or     *
 * implied warranty. See the GNU General Public License for more details.    *
 *---------------------------------------------------------------------------*/

#ifndef __rec_syst_conv_code_h
#define __rec_syst_conv_code_h

#include <binary.h>
#include <vector.h>
#include <matrix.h>
//#include "specmat.h"
//#include "matfunc.h"
#include "convcode.h"
namespace SPUC {
class Rec_Syst_Conv_Code {
public:

  Rec_Syst_Conv_Code(void) {}

  void set_generator_polynomials(const ivec &gen, int constraint_length);

  void set_awgn_channel_parameters(double in_Ec, double in_N0);

  void set_scaling_factor(double in_Lc);

  void encode_tail(const bvec &input, bvec &tail, bmat &parity_bits);

  void encode(const bvec &input, bmat &parity_bits);

  void map_decode(const vec &rec_systematic, const mat &rec_parity, const vec &extrinsic_input, vec &extrinsic_output, 
                  bool set_terminated = false);

  void log_decode(const vec &rec_systematic, const mat &rec_parity, const vec &extrinsic_input, vec &extrinsic_output,
                  bool set_terminated = false, string metric = "LOGMAX");

  void log_decode_n2(const vec &rec_systematic, const vec &rec_parity, const vec &extrinsic_input, vec &extrinsic_output, 
                     bool in_terminated = false, string metric = "LOGMAX");

private:

  void state_transition(int s_prim, int input_bit, int &s, int &parity);
  void reverse_state_transition(int s, int input_bit, int &s_prim, int &parity);
  int calc_state_transition(const int instate, const int input, ivec &parity);

  int n, K, m;
  ivec gen_pol, gen_pol_rev;
  int encoder_state, Nstates;
  double rate, Ec, N0, Lc;
  imat state_trans, output_parity, rev_state_trans, rev_output_parity;
  bool terminated;
  mat gamma, alpha, beta;
  vec denom;
  double ln2;

};
}
#endif // __rec_syst_conv_code_h

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