/*************************************************************************** *    convolution.c  - Software Radio convolutional coding module *                           ------------------- *   begin                :  03/12/10 *   authors              :  Roman Hofer *   emails               :  roman.hofer@epfl.ch ***************************************************************************//*************************************************************************** *                                Changes *                                ------- * date - name - description * **************************************************************************//*************************************************************************** *                                                                         * *   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 2 of the License, or     * *   (at your option) any later version.                                   * *                                                                         * ***************************************************************************/#include "spc.h"/** * This module does a convolutional encoding/decoding. * The code can be chosen according to the following parameters * n Number of transmitted bits per k data bits * k Number of data bits per n transmitted bits * m Number of memory registers * polys Array of polynome definition. The number of polynomes must be equal to n * * Any values of n and k are legal, but a useful code can only be achieved * if k>=n and n<=m * * The transmitted code blocklength is >= n/k times the data blocklength. Thus * a large n/k reduces capacity but improves error resistance due to higher redundancy. * * For implementation reasons, m is limited to 32 (number of bits in an int value). * Still, for memory and performance reasons only m << 32 are possible */#define DBG_LVL 0int rcv_module_init( void );void rcv_module_exit( void );int send_module_init( void );void send_module_exit( void );/* * Just call the two init-functions */int spc_module_init(void) {  if( rcv_module_init() < 0 ) {    PR_DBG( 0, "Couldn't init rcv-part\n" );    return -1;  }  if ( send_module_init() < 0 ) {    rcv_module_exit();    PR_DBG( 0, "Couldn't init send-part\n" );    return -1;  }  return 0;}/* * And call the two exit-funcitons */void spc_module_exit( void ) {  rcv_module_exit();  send_module_exit();}module_init( spc_module_init );module_exit( spc_module_exit );