lmseq.h

在linux系统下开发研究移动通信的工具型代码

#ifndef _MSEQL_H
#define _MSEQL_H

/*
 * $Log: lmseq.h,v $
 * Revision 1.2  2000/05/15 11:08:32  bjc97r
 * sys/types.h has been included so that unsigned long can be recognised.
 *
 * Revision 1.1  2000/05/03 14:30:04  bjc97r
 * Initial revision
 *
 *
 */

#include <sys/types.h>

typedef struct {
  unsigned long state0; /* lower 32 bits of PN register state */
  unsigned long state1; /* upper 32 bits of PN register state */
  unsigned long mask0;  /* lower 32 bits of PN mask to get the next state */
  unsigned long mask1;  /* upper 32 bits of PN mask to get the next state */
} LMseq;

/*
 * lmseq_create() differs from mseq_create() in that it can handle
 * higher order generator polynomials up to 63.
 * The polynomial should be given by a string representation of
 * octal value of the polynomial without leading '0'. For example,
 * mseql = mseql_create( 40, "20000012000005", 0, 1 ) .
 * seed1 corresponds to upper 32bits and seed0 lower 32bits 
 * as the initial state of the PN registers.
 */
LMseq * lmseq_create( unsigned deg, char * poly,
		      unsigned long seed1, unsigned long seed0 );

/* lmseql_free() deallocates the memory space for the m-sequence generator. */
void lmseq_free( LMseq * id );

/*
 * lmseq() gives the next m-sequence bit of the m-sequence generator.
 * The generated bit is unipolar, ie 1 or 0.
 */
char lmseq( LMseq * id );

#endif  /* _MSEQL_H */