library.c

This a framework to test new ideas in transmission technology. Actual development is a LDPC-coder in

/***************************************************************************
 *    function_name.c  - Software Radio template module
 *                           -------------------
 *   begin                :  date
 *   authors              :  name
 *   emails               :  email address
 ***************************************************************************/

/***************************************************************************
 *                                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 "library.h"


/**
 * Please see header file for description
 */
int countOnes(REG_STATUS in,int numBits) {
  REG_STATUS chkMask=0x01;
  int ctr=0;
  int i;
  //only bits 0..numBits are relevant (rest unused)
  for (i=0;i<numBits;i++) {
    //Check if a one was found
    if ((in & chkMask) !=0)
      ctr++;
    //Shift mask to check next bit
    chkMask<<=1;
  }
  return ctr;
}

/**
 * Please see header file for description
 */
int hammingDistance(REG_STATUS input1,REG_STATUS input2,int numBits) {
  //hamming distance is the number of 1-Bits of the XOR of the two values
  return countOnes(input1^input2,numBits);
}