3gpplte_turbo_decoder.c 28.4 KB
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/*
 * Licensed to the OpenAirInterface (OAI) Software Alliance under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The OpenAirInterface Software Alliance licenses this file to You under
 * the OAI Public License, Version 1.0  (the "License"); you may not use this file
 * except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.openairinterface.org/?page_id=698
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *-------------------------------------------------------------------------------
 * For more information about the OpenAirInterface (OAI) Software Alliance:
 *      contact@openairinterface.org
 */

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/* file: 3gpplte_turbo_decoder.c
   purpose: Fixed-point routines for implementing max-logmap decoding of Turbo-coded (DLSCH) transport channels from 36-212, V8.6 2009-03
   Modified from TI C6x reference design.
   currently maintained in openairinterface.org by R. Knopp (knopp@eurecom.fr)
   Note: This is a reference design for the sse version (3gpplte_turbo_decoder_sse.c)

*/

#include "PHY/defs.h"
#include "PHY/CODING/defs.h"
#include "PHY/CODING/lte_interleaver_inline.h"
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#include "PHY/sse_intrin.h"
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/*
// 3gpp2 polynomials
#define M0T -m11
#define M0B m11
#define M1T m11
#define M1B -m11
#define M2T -m10
#define M2B m10
#define M3T m10
#define M3B -m10
#define M4T m10
#define M4B -m10
#define M5T -m10
#define M5B m10
#define M6T m11
#define M6B -m11
#define M7T -m11
#define M7B m11
*/

// 3gpplte polynomials
#define m00 (-m11)
#define m01 (-m10)

#define M0T m00
#define M0B m11
#define M1T m11
#define M1B m00
#define M2T m10
#define M2B m01
#define M3T m01
#define M3B m10
#define M4T m01
#define M4B m10
#define M5T m10
#define M5B m01
#define M6T m11
#define M6B m00
#define M7T m00
#define M7B m11

#define M0T_TERM m00
#define M1T_TERM m11
#define M2T_TERM m10
#define M3T_TERM m01
#define M4T_TERM m01
#define M5T_TERM m10
#define M6T_TERM m11
#define M7T_TERM m00
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/*
// 3GPP2 AlphaBeta
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#define ALPHA_BETA_1m00 alpha[(k-1)*STATES+0] + beta[k*STATES+0]
#define ALPHA_BETA_1m11 alpha[(k-1)*STATES+0] + beta[k*STATES+4]
#define ALPHA_BETA_2m11 alpha[(k-1)*STATES+1] + beta[k*STATES+0]
#define ALPHA_BETA_2m00 alpha[(k-1)*STATES+1] + beta[k*STATES+4]
#define ALPHA_BETA_1m01 alpha[(k-1)*STATES+2] + beta[k*STATES+1]
#define ALPHA_BETA_1m10 alpha[(k-1)*STATES+2] + beta[k*STATES+5]
#define ALPHA_BETA_2m10 alpha[(k-1)*STATES+3] + beta[k*STATES+1]
#define ALPHA_BETA_2m01 alpha[(k-1)*STATES+3] + beta[k*STATES+5]
#define ALPHA_BETA_3m10 alpha[(k-1)*STATES+4] + beta[k*STATES+2]
#define ALPHA_BETA_3m01 alpha[(k-1)*STATES+4] + beta[k*STATES+6]
#define ALPHA_BETA_4m01 alpha[(k-1)*STATES+5] + beta[k*STATES+2]
#define ALPHA_BETA_4m10 alpha[(k-1)*STATES+5] + beta[k*STATES+6]
#define ALPHA_BETA_3m11 alpha[(k-1)*STATES+6] + beta[k*STATES+3]
#define ALPHA_BETA_3m00 alpha[(k-1)*STATES+6] + beta[k*STATES+7]
#define ALPHA_BETA_4m00 alpha[(k-1)*STATES+7] + beta[k*STATES+3]
#define ALPHA_BETA_4m11 alpha[(k-1)*STATES+7] + beta[k*STATES+7]
*/

#define ALPHA_BETA_1m00 alpha[(k-1)*STATES+0] + beta[k*STATES+0]
#define ALPHA_BETA_1m11 alpha[(k-1)*STATES+0] + beta[k*STATES+4]
#define ALPHA_BETA_2m11 alpha[(k-1)*STATES+1] + beta[k*STATES+0]
#define ALPHA_BETA_2m00 alpha[(k-1)*STATES+1] + beta[k*STATES+4]
#define ALPHA_BETA_1m10 alpha[(k-1)*STATES+2] + beta[k*STATES+1]
#define ALPHA_BETA_1m01 alpha[(k-1)*STATES+2] + beta[k*STATES+5]
#define ALPHA_BETA_2m10 alpha[(k-1)*STATES+3] + beta[k*STATES+5]
#define ALPHA_BETA_2m01 alpha[(k-1)*STATES+3] + beta[k*STATES+1]
#define ALPHA_BETA_3m10 alpha[(k-1)*STATES+4] + beta[k*STATES+6]
#define ALPHA_BETA_3m01 alpha[(k-1)*STATES+4] + beta[k*STATES+2]
#define ALPHA_BETA_4m01 alpha[(k-1)*STATES+5] + beta[k*STATES+6]
#define ALPHA_BETA_4m10 alpha[(k-1)*STATES+5] + beta[k*STATES+2]
#define ALPHA_BETA_3m11 alpha[(k-1)*STATES+6] + beta[k*STATES+3]
#define ALPHA_BETA_3m00 alpha[(k-1)*STATES+6] + beta[k*STATES+7]
#define ALPHA_BETA_4m00 alpha[(k-1)*STATES+7] + beta[k*STATES+3]
#define ALPHA_BETA_4m11 alpha[(k-1)*STATES+7] + beta[k*STATES+7]


typedef char Binary;
typedef short llr_t; // internal decoder data is 16-bit fixed
typedef short channel_t;

#define LLR_MAX 32767
#define LLR_MIN -32768
#define LLRTOT 16
#define MAX 32767//16383
#define FRAME_LENGTH_MAX 6144
#define STATES 8

void log_map_s (llr_t* systematic,channel_t* y_parity, llr_t* ext,unsigned short frame_length,unsigned char term_flag,unsigned char F);
void compute_gamma_s(llr_t* m11,llr_t* m10,llr_t* systematic, channel_t* y_parity, unsigned short frame_length,unsigned char term_flag);
void compute_alpha_s(llr_t*alpha,llr_t* m11,llr_t* m10, unsigned short frame_length,unsigned char F);
void compute_beta_s(llr_t* beta,llr_t* m11,llr_t* m10,llr_t* alpha, unsigned short frame_length,unsigned char F);
void compute_ext_s(llr_t* alpha,llr_t* beta,llr_t* m11,llr_t* m10,llr_t* extrinsic, llr_t* ap, unsigned short frame_length);

// global variables
//
llr_t alpha[(FRAME_LENGTH_MAX+3+1)*8];
llr_t beta[(FRAME_LENGTH_MAX+3+1)*8];
llr_t m11[(FRAME_LENGTH_MAX+3)];
llr_t m10[(FRAME_LENGTH_MAX+3)];


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void log_map_s(llr_t* systematic,channel_t* y_parity, llr_t* ext,unsigned short frame_length,unsigned char term_flag,unsigned char F)
{
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#ifdef DEBUG_LOGMAP
  unsigned short i;


  unsigned short argmax;
  llr_t max;

  printf("Gamma ...\n");
#endif //DEBUG_LOGMAP

  compute_gamma_s(m11,m10,systematic,y_parity,frame_length,term_flag);

#ifdef DEBUG_LOGMAP
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  for (i=0; i<frame_length+3; i++)
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    printf("Position %d : (%d,%d,%d,%d)\n",i,m11[i],m10[i],-m11[i],-m10[i]);
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  printf("\n");
  printf("Alpha ...\n");
#endif //DEBUG_LOGMAP

  compute_alpha_s(alpha,m11,m10,frame_length,F);

#ifdef DEBUG_LOGMAP
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  for (i=0; i<frame_length+4; i++) {
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    printf("Position %d : (%d,%d,%d,%d) (%d,%d,%d,%d,%d,%d,%d,%d) -> ",i,
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           -m11[i],m10[i],m11[i],-m10[i],alpha[(i<<3) + 0],
           alpha[(i<<3) + 1],
           alpha[(i<<3) + 2],
           alpha[(i<<3) + 3],
           alpha[(i<<3) + 4],
           alpha[(i<<3) + 5],
           alpha[(i<<3) + 6],
           alpha[(i<<3) + 7]);
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    argmax = 0;
    max = alpha[(i<<3)];
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    if (max<alpha[(i<<3) + 1]) {
      argmax=1;
      max = alpha[(i<<3) + 1];
    }
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    if (max<alpha[(i<<3) + 2]) {
      argmax=2;
      max = alpha[(i<<3) + 2];
    }
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    if (max<alpha[(i<<3) + 3]) {
      argmax=3;
      max = alpha[(i<<3) + 3];
    }
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    if (max<alpha[(i<<3) + 4]) {
      argmax=4;
      max = alpha[(i<<3) + 4];
    }
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    if (max<alpha[(i<<3) + 5]) {
      argmax=5;
      max = alpha[(i<<3) + 5];
    }
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    if (max<alpha[(i<<3) + 6]) {
      argmax=6;
      max = alpha[(i<<3) + 6];
    }
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    if (max<alpha[(i<<3) + 7]) {
      argmax=7;
      max = alpha[(i<<3) + 7];
    }

    printf("argmax = %d\n",argmax);
  }
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  printf("Beta ...\n");

#endif //DEBUG_LOGMAP

  compute_beta_s(beta,m11,m10,alpha,frame_length,F);

#ifdef DEBUG_LOGMAP
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  for (i=0; i<=frame_length+3; i++) {
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    printf("Position %d : (%d,%d,%d,%d,%d,%d,%d,%d)->",i,
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           beta[(i<<3) + 0],
           beta[(i<<3) + 1],
           beta[(i<<3) + 2],
           beta[(i<<3) + 3],
           beta[(i<<3) + 4],
           beta[(i<<3) + 5],
           beta[(i<<3) + 6],
           beta[(i<<3) + 7]);
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    argmax = 0;
    max = beta[(i<<3)];
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    if (max<beta[(i<<3) + 1]) {
      argmax=1;
      max = beta[(i<<3) + 1];
    }
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    if (max<beta[(i<<3) + 2]) {
      argmax=2;
      max = beta[(i<<3) + 2];
    }
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    if (max<beta[(i<<3) + 3]) {
      argmax=3;
      max = beta[(i<<3) + 3];
    }
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    if (max<beta[(i<<3) + 4]) {
      argmax=4;
      max = beta[(i<<3) + 4];
    }
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    if (max<beta[(i<<3) + 5]) {
      argmax=5;
      max = beta[(i<<3) + 5];
    }
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    if (max<beta[(i<<3) + 6]) {
      argmax=6;
      max = beta[(i<<3) + 6];
    }
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    if (max<beta[(i<<3) + 7]) {
      argmax=7;
      max = beta[(i<<3) + 7];
    }

    printf("argmax = %d\n",argmax);
  }
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  printf("Extrinsic ...\n");
#endif //DEBUG_LOGMAP

  compute_ext_s(alpha,beta,m11,m10,ext,systematic,frame_length);

#ifdef DEBUG_LOGMAP
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  for (i=0; i<frame_length+3; i++)
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    printf("Position %d : ext %d, ext+sys %d\n",i,
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           ext[i],ext[i]+systematic[i]);

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  printf("\n");
#endif //DEBUG_LOGMAP

}

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inline int SAT_ADD(int a,int b,int m)
{
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  if (a+b > m) {
#ifdef DEBUG_LOGMAP
    printf("***\n");
#endif
    return(m);
  }

  if (a+b < -m) {
#ifdef DEBUG_LOGMAP
    printf("***\n");
#endif
    return(-m);
  }

  return(a+b);
}

void compute_gamma_s(llr_t* m11,llr_t* m10,llr_t* systematic,channel_t* y_parity,
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                     unsigned short frame_length,unsigned char term_flag)
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{
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  int k;
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  for (k=0; k<frame_length; k++) {
    m11[k] = (systematic[k]+y_parity[k])/2;
    m10[k] = (systematic[k]-y_parity[k])/2;
    //      printf("gamma %d : (%d,%d) -> (%d,%d)\n",k,systematic[k],y_parity[k],m11[k],m10[k]);
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  }

  // Compute metrics for trellis termination
  if (term_flag == 0) { // This is for the termination of the first code
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    for (k=frame_length; k<frame_length+3; k++) {
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      m11[k] = (systematic[k]+y_parity[k])/2;
      m10[k] = (systematic[k]-y_parity[k])/2;
      //      printf("gamma %d : (%d,%d) -> (%d,%d)\n",k,systematic[k],y_parity[k],m11[k],m10[k]);
    }
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  } else {
    for (k=frame_length; k<frame_length+3; k++) {
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      m11[k] = (systematic[k+3]+y_parity[k])/2;
      m10[k] = (systematic[k+3]-y_parity[k])/2;
      //      printf("gamma %d : (%d,%d) -> (%d,%d)\n",k,systematic[k],y_parity[k],m11[k],m10[k]);
    }
  }
}

short systematic0[6144],systematic1[6144],systematic2[6144],yparity1[6144],yparity2[6144];

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void compute_alpha_s(llr_t* alpha,llr_t* m_11,llr_t* m_10,unsigned short frame_length,unsigned char F)
{
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  int k,i;
  llr_t m11,m10;
  llr_t old0,old1,old2, old3, old4, old5, old6, old7;
  llr_t new0,new1,new2, new3, new4, new5, new6, new7;
  llr_t m_b0,m_b1,m_b2, m_b3, m_b4, m_b5, m_b6, m_b7;
  // initialize log_alpha[0][m]
  llr_t alpha_max;

  old0 = 0;
  old1 = -MAX/2;
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  old2 = -MAX/2;
  old3 = -MAX/2;
  old4 = -MAX/2;
  old5 = -MAX/2;
  old6 = -MAX/2;
  old7 = -MAX/2;
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  alpha[0*(frame_length)+0] = old0;
  alpha[0*(frame_length)+1] = old1;
  alpha[0*(frame_length)+2] = old2;
  alpha[0*(frame_length)+3] = old3;
  alpha[0*(frame_length)+4] = old4;
  alpha[0*(frame_length)+5] = old5;
  alpha[0*(frame_length)+6] = old6;
  alpha[0*(frame_length)+7] = old7;

  //
  // compute log_alpha[k][m]
  // Steady-state portion
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  for (k=1; k<=F; k++)
    for (i=0; i<8; i++)
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      alpha[i+(k*8)] = alpha[i];

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  for (k=1; k<=frame_length; k++) {
    m11=m_11[k-1];
    m10=m_10[k-1];
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    m_b0 = SAT_ADD(old1,M1T,MAX);
    m_b4 = SAT_ADD(old1,M1B,MAX);
    m_b1 = SAT_ADD(old3,M3T,MAX);
    m_b5 = SAT_ADD(old3,M3B,MAX);
    m_b2 = SAT_ADD(old5,M5T,MAX);
    m_b6 = SAT_ADD(old5,M5B,MAX);
    m_b3 = SAT_ADD(old7,M7T,MAX);
    m_b7 = SAT_ADD(old7,M7B,MAX);
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    new0 = SAT_ADD(old0,M0T,MAX);
    new4 = SAT_ADD(old0,M0B,MAX);
    new1 = SAT_ADD(old2,M2T,MAX);
    new5 = SAT_ADD(old2,M2B,MAX);
    new2 = SAT_ADD(old4,M4T,MAX);
    new6 = SAT_ADD(old4,M4B,MAX);
    new3 = SAT_ADD(old6,M6T,MAX);
    new7 = SAT_ADD(old6,M6B,MAX);
    //      printf("Output %d (%d,%d)\n",k-1,systematic0[k-1],yparity1[k-1]);
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    //      printf("(m_b0 %d,new0 %d),(m_b1 %d,new1 %d),(m_b2 %d,new2 %d),(m_b3 %d,new3 %d),(m_b4 %d,new4 %d),(m_b5 %d,new5 %d),(m_b6 %d,new6 %d),(m_b7 %d,new7 %d)\n",m_b0,new0,m_b1,new1,m_b2,new2,m_b3,new3,m_b4,new4,m_b5,new5,m_b6,new6,m_b7,new7);

    if (m_b0 > new0) new0=m_b0;

    alpha[k*STATES + 0] = new0;
    old0=new0;

    if (m_b4 > new4) new4=m_b4;

    alpha[k*STATES + 4] = new4;
    old4=new4;

    if (m_b1 > new1) new1=m_b1;

    alpha[k*STATES + 1] = new1;
    old1=new1;

    if (m_b5 > new5) new5=m_b5;

    alpha[k*STATES + 5] = new5;
    old5=new5;

    if (m_b2 > new2) new2=m_b2;

    alpha[k*STATES + 2] = new2;
    old2=new2;

    if (m_b6 > new6) new6=m_b6;

    alpha[k*STATES + 6] = new6;
    old6=new6;

    if (m_b3 > new3) new3=m_b3;

    alpha[k*STATES + 3] = new3;
    old3=new3;

    if (m_b7 > new7) new7=m_b7;

    alpha[k*STATES + 7] = new7;
    old7=new7;

    alpha_max = alpha[(STATES*k) + 0];

    if(alpha[(STATES*k) + 1]>alpha_max)
      alpha_max = alpha[(STATES*k) + 1];

    if(alpha[(STATES*k) + 2]>alpha_max)
      alpha_max = alpha[(STATES*k) + 2];

    if(alpha[(STATES*k) + 3]>alpha_max)
      alpha_max = alpha[(STATES*k) + 3];

    if(alpha[(STATES*k) + 4]>alpha_max)
      alpha_max = alpha[(STATES*k) + 4];

    if(alpha[(STATES*k) + 5]>alpha_max)
      alpha_max = alpha[(STATES*k) + 5];

    if(alpha[(STATES*k) + 6]>alpha_max)
      alpha_max = alpha[(STATES*k) + 6];

    if(alpha[(STATES*k) + 7]>alpha_max)
      alpha_max = alpha[(STATES*k) + 7];

    alpha[(STATES*k)+0]-=alpha_max;
    alpha[(STATES*k)+1]-=alpha_max;
    alpha[(STATES*k)+2]-=alpha_max;
    alpha[(STATES*k)+3]-=alpha_max;
    alpha[(STATES*k)+4]-=alpha_max;
    alpha[(STATES*k)+5]-=alpha_max;
    alpha[(STATES*k)+6]-=alpha_max;
    alpha[(STATES*k)+7]-=alpha_max;
    new0=alpha[(STATES*k)+0];
    new1=alpha[(STATES*k)+1];
    new2=alpha[(STATES*k)+2];
    new3=alpha[(STATES*k)+3];
    new4=alpha[(STATES*k)+4];
    new5=alpha[(STATES*k)+5];
    new6=alpha[(STATES*k)+6];
    new7=alpha[(STATES*k)+7];
  }

  for (k=frame_length+1; k<=frame_length+3; k++) {
    m11=m_11[k-1];
    m10=m_10[k-1];
    m_b0 = SAT_ADD(old1,M1T_TERM,MAX);
    m_b1 = SAT_ADD(old3,M3T_TERM,MAX);
    m_b2 = SAT_ADD(old5,M5T_TERM,MAX);
    m_b3 = SAT_ADD(old7,M7T_TERM,MAX);

    new0 = SAT_ADD(old0,M0T_TERM,MAX);
    new1 = SAT_ADD(old2,M2T_TERM,MAX);
    new2 = SAT_ADD(old4,M4T_TERM,MAX);
    new3 = SAT_ADD(old6,M6T_TERM,MAX);
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#ifdef DEBUG_LOGMAP
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    printf("alpha term: m00 %d, m10 %d : (%d,%d,%d,%d) (%d,%d,%d,%d) (%d,%d,%d,%d) (%d,%d,%d,%d)\n",
           m00,m10,old0,old1,m_b0,new0,old2,old3,m_b1,new1,old3,old4,m_b2,new2,old6,old7,m_b3,new3);
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#endif //DEBUG_LOGMAP

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    if (m_b0 > new0) new0=m_b0;
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    alpha[k*STATES + 0] = new0;
    old0=new0;

    if (m_b2 > new2) new2=m_b2;

    alpha[k*STATES + 2] = new2;
    old2=new2;

    if (m_b1 > new1) new1=m_b1;

    alpha[k*STATES + 1] = new1;
    old1=new1;

    if (m_b3 > new3) new3=m_b3;

    alpha[k*STATES + 3] = new3;
    old3=new3;

    alpha_max = alpha[(STATES*k) + 0];

    if(alpha[(STATES*k) + 1]>alpha_max)
      alpha_max = alpha[(STATES*k) + 1];

    if(alpha[(STATES*k) + 2]>alpha_max)
      alpha_max = alpha[(STATES*k) + 2];

    if(alpha[(STATES*k) + 3]>alpha_max)
      alpha_max = alpha[(STATES*k) + 3];

    alpha[(STATES*k)+0]-=alpha_max;
    alpha[(STATES*k)+1]-=alpha_max;
    alpha[(STATES*k)+2]-=alpha_max;
    alpha[(STATES*k)+3]-=alpha_max;

    new0=alpha[(STATES*k)+0];
    new1=alpha[(STATES*k)+1];
    new2=alpha[(STATES*k)+2];
    new3=alpha[(STATES*k)+3];
  }
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}

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void compute_beta_s(llr_t* beta,llr_t *m_11,llr_t* m_10,llr_t* alpha,unsigned short frame_length,unsigned char F)
{
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  int k,i;
  llr_t old0, old1, old2, old3, old4, old5, old6, old7;
  llr_t new0, new1, new2, new3, new4, new5, new6, new7;
  llr_t m_b0, m_b1, m_b2, m_b3, m_b4,m_b5, m_b6, m_b7;
557
  llr_t m11,m10;
558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587
  llr_t beta_max;

  //  int m_max;

  //  llr_t max1, temp1, max2, temp2;

  //  int m_max1, m_max2;

  //
  // initialize the first stage;
  // for state for which alpha iz maximum, set log_beta to 0,
  // set the other ones to MAX.

  /*
  m_max1 = 0;
  max1 = alpha[((frame_length+3)*STATES)+0];
  temp1 = alpha[((frame_length+3)*STATES)+1];
  if (temp1 > max1) { m_max1 = 1; max1 = temp1;};
  temp1 = alpha[((frame_length+3)*STATES)+2];
  if (temp1 > max1) { m_max1 = 2; max1 = temp1;};
  temp1 = alpha[((frame_length+3)*STATES)+3];
  if (temp1 > max1) { m_max1 = 3; max1 = temp1;};
  m_max2 = 7; max2 = alpha[((frame_length+3)*STATES)+7];
  temp2 = alpha[((frame_length+3)*STATES)+6];
  if (temp2 > max2) { m_max2 = 6; max2 = temp2;};
  temp2 = alpha[((frame_length+3)*STATES)+5];
  if (temp2 > max2) { m_max2 = 5; max2 = temp2;};
  temp2 = alpha[((frame_length+3)*STATES)+4];
  if (temp2 > max2) { m_max2 = 4; max2 = temp2;};
  if (max2 > max1) m_max1 = m_max2;
588

589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680

  if (m_max1==0) old0=0; else old0 = -MAX/2;
  if (m_max1==1) old1=0; else old1 = -MAX/2;
  if (m_max1==2) old2=0; else old2 = -MAX/2;
  if (m_max1==3) old3=0; else old3 = -MAX/2;
  if (m_max1==4) old4=0; else old4 = -MAX/2;
  if (m_max1==5) old5=0; else old5 = -MAX/2;
  if (m_max1==6) old6=0; else old6 = -MAX/2;
  if (m_max1==7) old7=0; else old7 = -MAX/2;
  */

  /*
  // Initialise zero state because of termination
  beta[(STATES*(frame_length+3)) + 0] = 0;
  beta[(STATES*(frame_length+3)) + 1] = -MAX/2;
  beta[(STATES*(frame_length+3)) + 2] = -MAX/2;
  beta[(STATES*(frame_length+3)) + 3] = -MAX/2;
  beta[(STATES*(frame_length+3)) + 4] = -MAX/2;
  beta[(STATES*(frame_length+3)) + 5] = -MAX/2;
  beta[(STATES*(frame_length+3)) + 6] = -MAX/2;
  beta[(STATES*(frame_length+3)) + 7] = -MAX/2;

  for (k=0;k<F;k++)
    for (i=0;i<8;i++)
      beta[i+(k*8)] = beta[i];

  old0 = 0;
  old1 = -MAX/2;
  old2 = -MAX/2;
  old3 = -MAX/2;
  old4 = -MAX/2;
  old5 = -MAX/2;
  old6 = -MAX/2;
  old7 = -MAX/2;

  //
  // compute beta[k][m]
   //
  for (k=(frame_length+2);k>=frame_length;k--)
    {
      m11=m_11[k];
      m10=m_10[k];
      new0 = SAT_ADD(old0,M0T_TERM,MAX);
      new1 = SAT_ADD(old0,M1T_TERM,MAX);
      new2 = SAT_ADD(old1,M2T_TERM,MAX);
      new3 = SAT_ADD(old1,M3T_TERM,MAX);
      new4 = SAT_ADD(old2,M4T_TERM,MAX);
      new5 = SAT_ADD(old2,M5T_TERM,MAX);
      new6 = SAT_ADD(old3,M6T_TERM,MAX);
      new7 = SAT_ADD(old3,M7T_TERM,MAX);

      beta[k*STATES + 0] = new0;
      old0=new0;

      beta[k*STATES + 1] = new1;
      old1=new1;

      beta[k*STATES + 2] = new2;
      old2=new2;

      beta[k*STATES + 3] = new3;
      old3=new3;

      beta[k*STATES + 4] = new4;
      old4=new4;

      beta[k*STATES + 5] = new5;
      old5=new5;

      beta[k*STATES + 6] = new6;
      old6=new6;

      beta[k*STATES + 7] = new7;
      old7=new7;
    }
  */


  beta[(STATES*(frame_length)) + 0] = alpha[(STATES*frame_length) + 0];
  beta[(STATES*(frame_length)) + 1] = alpha[(STATES*frame_length) + 1];
  beta[(STATES*(frame_length)) + 2] = alpha[(STATES*frame_length) + 2];
  beta[(STATES*(frame_length)) + 3] = alpha[(STATES*frame_length) + 3];
  beta[(STATES*(frame_length)) + 4] = alpha[(STATES*frame_length) + 4];
  beta[(STATES*(frame_length)) + 5] = alpha[(STATES*frame_length) + 5];
  beta[(STATES*(frame_length)) + 6] = alpha[(STATES*frame_length) + 6];
  beta[(STATES*(frame_length)) + 7] = alpha[(STATES*frame_length) + 7];


  old0 = beta[(STATES*frame_length)+0];
  old1 = beta[(STATES*frame_length)+1];
  old2 = beta[(STATES*frame_length)+2];
  old3 = beta[(STATES*frame_length)+3];
681
  old4 = beta[(STATES*frame_length)+4];
682 683 684 685
  old5 = beta[(STATES*frame_length)+5];
  old6 = beta[(STATES*frame_length)+6];
  old7 = beta[(STATES*frame_length)+7];

686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757
  for (k=(frame_length-1); k>=0; k--) {
    m11=m_11[k];
    m10=m_10[k];
    m_b0 = SAT_ADD(old4,M0B,MAX);
    m_b1 = SAT_ADD(old4,M1B,MAX);
    m_b2 = SAT_ADD(old5,M2B,MAX);
    m_b3 = SAT_ADD(old5,M3B,MAX);
    m_b4 = SAT_ADD(old6,M4B,MAX);
    m_b5 = SAT_ADD(old6,M5B,MAX);
    m_b6 = SAT_ADD(old7,M6B,MAX);
    m_b7 = SAT_ADD(old7,M7B,MAX);
    new0 = SAT_ADD(old0,M0T,MAX);
    new1 = SAT_ADD(old0,M1T,MAX);
    new2 = SAT_ADD(old1,M2T,MAX);
    new3 = SAT_ADD(old1,M3T,MAX);
    new4 = SAT_ADD(old2,M4T,MAX);
    new5 = SAT_ADD(old2,M5T,MAX);
    new6 = SAT_ADD(old3,M6T,MAX);
    new7 = SAT_ADD(old3,M7T,MAX);



    if (m_b0 > new0) new0=m_b0;

    beta[k*STATES + 0] = new0;
    old0=new0;

    if (m_b1 > new1) new1=m_b1;

    beta[k*STATES + 1] = new1;
    old1=new1;

    if (m_b2 > new2) new2=m_b2;

    beta[k*STATES + 2] = new2;
    old2=new2;

    if (m_b3 > new3) new3=m_b3;

    beta[k*STATES + 3] = new3;
    old3=new3;

    if (m_b4 > new4) new4=m_b4;

    beta[k*STATES + 4] = new4;
    old4=new4;

    if (m_b5 > new5) new5=m_b5;

    beta[k*STATES + 5] = new5;
    old5=new5;

    if (m_b6 > new6) new6=m_b6;

    beta[k*STATES + 6] = new6;
    old6=new6;

    if (m_b7 > new7) new7=m_b7;

    beta[k*STATES + 7] = new7;
    old7=new7;

    beta_max = beta[(STATES*k) + 0];

    if(beta[(STATES*k) + 1]>beta_max)
      beta_max = beta[(STATES*k) + 1];

    if(beta[(STATES*k) + 2]>beta_max)
      beta_max = beta[(STATES*k) + 2];

    if(beta[(STATES*k) + 3]>beta_max)
      beta_max = beta[(STATES*k) + 3];
758

759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798
    if(beta[(STATES*k) + 4]>beta_max)
      beta_max = beta[(STATES*k) + 4];

    if(beta[(STATES*k) + 5]>beta_max)
      beta_max = beta[(STATES*k) + 5];

    if(beta[(STATES*k) + 6]>beta_max)
      beta_max = beta[(STATES*k) + 6];

    if(beta[(STATES*k) + 7]>beta_max)
      beta_max = beta[(STATES*k) + 7];

    beta[(STATES*k)+0]-=beta_max;
    beta[(STATES*k)+1]-=beta_max;
    beta[(STATES*k)+2]-=beta_max;
    beta[(STATES*k)+3]-=beta_max;
    beta[(STATES*k)+4]-=beta_max;
    beta[(STATES*k)+5]-=beta_max;
    beta[(STATES*k)+6]-=beta_max;
    beta[(STATES*k)+7]-=beta_max;

    new0=beta[(STATES*k)+0];
    new1=beta[(STATES*k)+1];
    new2=beta[(STATES*k)+2];
    new3=beta[(STATES*k)+3];
    new4=beta[(STATES*k)+4];
    new5=beta[(STATES*k)+5];
    new6=beta[(STATES*k)+6];
    new7=beta[(STATES*k)+7];
    /*
    if (((k%(frame_length>>3))==0)&&(k>0)) {

    alpha[((k)*STATES)+0]=beta[((k)*STATES)+0]
    alpha[((k)*STATES)+1]=beta[((k)*STATES)+1];
    alpha[((k)*STATES)+2]=beta[((k)*STATES)+2];
    alpha[((k)*STATES)+3]=beta[((k)*STATES)+3];
    alpha[((k)*STATES)+4]=beta[((k)*STATES)+4];
    alpha[((k)*STATES)+5]=beta[((k)*STATES)+5];
    alpha[((k)*STATES)+6]=beta[((k)*STATES)+6];
    alpha[((k)*STATES)+7]=beta[((k)*STATES)+7];
799
    }
800 801
    */
  }
802 803 804 805 806 807 808
}
void compute_ext_s(llr_t* alpha,llr_t* beta,llr_t* m_11,llr_t* m_10,llr_t* ext, llr_t* systematic,unsigned short frame_length)
{
  int k;
  llr_t m11,m10;
  llr_t m00_1,m11_1,m00_2,m11_2,m00_3,m11_3,m00_4,m11_4;
  llr_t m01_1,m10_1,m01_2,m10_2,m01_3,m10_3,m01_4,m10_4;
809

810 811 812
  //
  // LLR computation
  //
813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866
  for (k=1; k<=(frame_length+3); k++) {
    m00_4 = ALPHA_BETA_4m00;
    m11_4 = ALPHA_BETA_4m11;
    m00_3 = ALPHA_BETA_3m00;
    m11_3 = ALPHA_BETA_3m11;
    m00_2 = ALPHA_BETA_2m00;
    m11_2 = ALPHA_BETA_2m11;
    m11_1 = ALPHA_BETA_1m11;
    m00_1 = ALPHA_BETA_1m00;
    m01_4 = ALPHA_BETA_4m01;
    m10_4 = ALPHA_BETA_4m10;
    m01_3 = ALPHA_BETA_3m01;
    m10_3 = ALPHA_BETA_3m10;
    m01_2 = ALPHA_BETA_2m01;
    m10_2 = ALPHA_BETA_2m10;
    m10_1 = ALPHA_BETA_1m10;
    m01_1 = ALPHA_BETA_1m01;

    if (m01_2 > m01_1) m01_1 = m01_2;

    if (m01_3 > m01_1) m01_1 = m01_3;

    if (m01_4 > m01_1) m01_1 = m01_4;

    if (m00_2 > m00_1) m00_1 = m00_2;

    if (m00_3 > m00_1) m00_1 = m00_3;

    if (m00_4 > m00_1) m00_1 = m00_4;

    if (m10_2 > m10_1) m10_1 = m10_2;

    if (m10_3 > m10_1) m10_1 = m10_3;

    if (m10_4 > m10_1) m10_1 = m10_4;

    if (m11_2 > m11_1) m11_1 = m11_2;

    if (m11_3 > m11_1) m11_1 = m11_3;

    if (m11_4 > m11_1) m11_1 = m11_4;

    m11=m_11[k-1];
    m10=m_10[k-1];
    m01_1 = SAT_ADD(m01_1,m01,MAX);
    m00_1 = SAT_ADD(m00_1,m00,MAX);
    m10_1 = SAT_ADD(m10_1,m10,MAX);
    m11_1 = SAT_ADD(m11_1,m11,MAX);

    if (m00_1 > m01_1) m01_1 = m00_1;

    if (m11_1 > m10_1) m10_1 = m11_1;

    ext[k-1] = SAT_ADD(m10_1,-SAT_ADD(m01_1,systematic[k-1],MAX),MAX);
867
#ifdef DEBUG_LOGMAP
868
    printf("Ext %d: m0 %d, m1 %d, syst %d ext %d\n",k-1,m01_1,m10_1,systematic[k-1],ext[k-1]);
869 870
#endif //DEBUG_LOGMAP

871
  };
872 873 874 875 876
}



unsigned char phy_threegpplte_turbo_decoder_scalar(llr_t *y,
877 878 879 880 881 882 883 884 885 886
    unsigned char *decoded_bytes,
    unsigned short n,
    unsigned short f1,
    unsigned short f2,
    unsigned char max_iterations,
    unsigned char crc_type,
    unsigned char F,
    unsigned char inst)
{

887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908
  /*  y is a pointer to the input
    decoded_bytes is a pointer to the decoded output
    n is the size in bits of the coded block, with the tail */
  short ext[n],ext2[n];

  //  short systematic0[n],systematic1[n],systematic2[n],yparity1[n],yparity2[n];
  llr_t *yp = y;
  unsigned short i,pi;
  unsigned char iteration_cnt=0;
  unsigned int crc,oldcrc;
  unsigned char crc_len,temp;

  if (crc_type > 3) {
    msg("Illegal crc length!\n");
    return 255;
  }

  switch (crc_type) {
  case CRC24_A:
  case CRC24_B:
    crc_len=3;
    break;
909

910 911 912
  case CRC16:
    crc_len=2;
    break;
913

914 915 916
  case CRC8:
    crc_len=1;
    break;
917

918 919 920 921
  default:
    crc_len=3;
  }

922 923 924 925 926 927 928
  for (i=0; i<n; i++) {
    systematic0[i] = *yp;
    yp++;
    yparity1[i] = *yp;
    yp++;
    yparity2[i] = *yp;
    yp++;
929 930 931 932 933
#ifdef DEBUG_LOGMAP
    printf("Position %d: (%d,%d,%d)\n",i,systematic0[i],yparity1[i],yparity2[i]);
#endif //DEBUG_LOGMAP

  }
934 935 936 937 938 939

  for (i=n; i<n+3; i++) {
    systematic0[i]= *yp ;
    yp++;
    yparity1[i] = *yp;
    yp++;
940 941 942 943
#ifdef DEBUG_LOGMAP
    printf("Term 1 (%d): %d %d\n",i,systematic0[i],yparity1[i]);
#endif //DEBUG_LOGMAP
  }
944 945 946 947 948 949

  for (i=n+3; i<n+6; i++) {
    systematic0[i]= *yp ;
    yp++;
    yparity2[i-3] = *yp;
    yp++;
950 951 952 953
#ifdef DEBUG_LOGMAP
    printf("Term 2 (%d): %d %d\n",i-3,systematic0[i],yparity2[i-3]);
#endif //DEBUG_LOGMAP
  }
954

955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974
#ifdef DEBUG_LOGMAP
  printf("\n");
#endif //DEBUG_LOGMAP



  // do log_map from first parity bit
  log_map_s(systematic0,yparity1,ext,n,0,F);


  while (iteration_cnt++ < max_iterations) {

#ifdef DEBUG_LOGMAP
    printf("\n*******************ITERATION %d\n\n",iteration_cnt);
#endif //DEBUG_LOGMAP

    threegpplte_interleaver_reset();
    pi=0;

    // compute input to second encoder by interleaving extrinsic info
975
    for (i=0; i<n; i++) { // steady-state portion
976 977 978
      systematic2[i] = (ext[pi] + systematic0[pi]);
      pi              = threegpplte_interleaver(f1,f2,n);
    }
979 980

    for (i=n; i<n+3; i++) { // termination
981 982
      systematic2[i] = (systematic0[i+8]);
    }
983 984

    // do log_map from second parity bit
985 986 987 988 989
    log_map_s(systematic2,yparity2,ext2,n,1,0);


    threegpplte_interleaver_reset();
    pi=0;
990 991

    for (i=0; i<n>>3; i++)
992
      decoded_bytes[i]=0;
993

994
    // compute input to first encoder and output
995
    for (i=0; i<n; i++) {
996 997 998
      systematic1[pi] = (ext2[i] + systematic0[pi]);
#ifdef DEBUG_LOGMAP
      printf("Second half %d: ext2[i] %d, systematic0[i] %d (e+s %d)\n",i,ext2[i],systematic0[pi],
999
             ext2[i]+systematic2[i]);
1000 1001 1002
#endif //DEBUG_LOGMAP

      if ((systematic2[i] + ext2[i]) > 0)
1003
        decoded_bytes[pi>>3] += (1 << (7-(pi&7)));
1004 1005 1006

      pi              = threegpplte_interleaver(f1,f2,n);
    }
1007 1008

    for (i=n; i<n+3; i++) {
1009 1010 1011
      systematic1[i] = (systematic0[i]);
#ifdef DEBUG_LOGMAP
      printf("Second half %d: ext2[i] %d, systematic0[i] %d (e+s %d)\n",i,ext2[i],systematic0[i],
1012
             ext2[i]+systematic2[i]);
1013 1014
#endif //DEBUG_LOGMAP
    }
1015

1016 1017 1018 1019 1020 1021 1022

    // check status on output

    oldcrc= *((unsigned int *)(&decoded_bytes[(n>>3)-crc_len]));

    switch (crc_type) {

1023
    case CRC24_A:
1024 1025
      oldcrc&=0x00ffffff;
      crc = crc24a(&decoded_bytes[F>>3],
1026
                   n-24-F)>>8;
1027 1028 1029
      temp=((uint8_t *)&crc)[2];
      ((uint8_t *)&crc)[2] = ((uint8_t *)&crc)[0];
      ((uint8_t *)&crc)[0] = temp;
1030 1031 1032 1033

      //           msg("CRC24_A = %x, oldcrc = %x (F %d)\n",crc,oldcrc,F);

      break;
1034

1035 1036 1037
    case CRC24_B:
      oldcrc&=0x00ffffff;
      crc = crc24b(decoded_bytes,
1038
                   n-24)>>8;
1039 1040 1041
      temp=((uint8_t *)&crc)[2];
      ((uint8_t *)&crc)[2] = ((uint8_t *)&crc)[0];
      ((uint8_t *)&crc)[0] = temp;
1042 1043 1044 1045

      //      msg("CRC24_B = %x, oldcrc = %x\n",crc,oldcrc);

      break;
1046

1047 1048 1049
    case CRC16:
      oldcrc&=0x0000ffff;
      crc = crc16(decoded_bytes,
1050
                  n-16)>>16;
1051 1052

      break;
1053

1054 1055 1056
    case CRC8:
      oldcrc&=0x000000ff;
      crc = crc8(decoded_bytes,
1057
                 n-8)>>24;
1058 1059 1060
      break;
    }

1061
    if (crc == oldcrc) {
1062 1063
      return(iteration_cnt);
    }
1064

1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084
    // do log_map from first parity bit
    if (iteration_cnt < max_iterations)
      log_map_s(systematic1,yparity1,ext,n,0,F);
  }

  return(iteration_cnt);
}

#ifdef TEST_DEBUG

int test_logmap8()
{
  unsigned char test[8];
  //_declspec(align(16))  char channel_output[512];
  //_declspec(align(16))  unsigned char output[512],decoded_output[16], *inPtr, *outPtr;

  short channel_output[512];
  unsigned char output[512],decoded_output[16];
  unsigned int i;

1085

1086 1087 1088 1089 1090 1091 1092 1093 1094
  test[0] = 7;
  test[1] = 0xa5;
  test[2] = 0;
  test[3] = 0xfe;
  test[4] = 0x1a;
  test[5] = 0x0;
  //  test[5] = 0x33;
  //  test[6] = 0x99;
  //  test[7] = 0;
1095

1096 1097

  threegpplte_turbo_encoder(test,
1098 1099 1100 1101
                            5,
                            output,
                            3,
                            10);
1102

1103
  for (i = 0; i < 132; i++) {
1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118
    channel_output[i] = 15*(2*output[i] - 1);
    //    printf("Position %d : %d\n",i,channel_output[i]);
  }

  memset(decoded_output,0,16);
  phy_threegpplte_turbo_decoder(channel_output,decoded_output,40,3,10,6,3);




}




1119 1120
void main()
{
1121 1122 1123 1124 1125 1126 1127 1128 1129


  test_logmap8();

}

#endif // TEST_DEBUG