library.h

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

#ifndef CONVOLUTIONLIBRARY_H__
#define CONVOLUTIONLIBRARY_H__

/**
* Type used to specify a status of the registers.
* The Bit at position j specifies the status of register j
* Because an unsigned int is used to model all registers, the number of registers (m)
* cannot exceed 32.
*/
typedef unsigned int REG_STATUS;

/**
* The value used as initialization in the metric array if the metric
* is not calculated, i.e. if the node in the trellis is not valid.
* It is set to max int value to always be greater than any calculated
* metric.
*/
#define METRIC_UNDEFINED 0x7fffffff	//max int


/************************************
* Counts the number of 1-Bits in a the numBits LSB
* of the bit pattern in
************************************/

/**
 * Counts the number of 1-Bits of some LSB (least significant bits)
 * of a bit pattern.
 *
 * @param in The bit pattern
 * @param numBits The number of LSB of in where the 1-Bits should be countes
 * @return The number of one-Bits in the numBits LSB of in
 */
int countOnes(REG_STATUS in,int numBits);

/**
 * Calculates the hamming distance of some LSB (least significant bits)
 * of two bit patterns.
 *
 * @param input1 The first bit pattern
 * @param input2 The second pattern
 * @param numBits The number of LSB of in where the hamming distance should be calculated
 * @return The hamming distance in the numBits LSB of input1 and input2
 */
int hammingDistance(REG_STATUS input1,REG_STATUS input2,int numBits);



#endif