test_ekasami.c

在linux系统下开发研究移动通信的工具型代码

/*
 * $Log: test_ekasami.c,v $
 * Revision 1.1  2000/05/03 14:30:04  bjc97r
 * Initial revision
 *
 */
char *id = "$Id: test_ekasami.c,v 1.1 2000/05/03 14:30:04 bjc97r Exp $";

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "ekasami.h"
#include "gf.h"
#include "u2long.h"


#define SZ_BUF 128

/* static u2long zero={0,0}; */
static u2long one={0,1};
static u2long two={0,2};

int main( int argc, char *argv[] )
{
  unsigned deg;
  char poly0[SZ_BUF], poly1[SZ_BUF];
  unsigned long poly2;

  EKasami *pn00, *pn01;
  EKasami *pn10, *pn11;

  u2long pn_size;
  u2long offset;

  if ( argc != 4 ) {
    fprintf(stderr, "%s: deg poly0 poly1\n", argv[0] );
    fprintf(stderr, " deg is a positive even interger.\n" );
    fprintf(stderr, " poly0 and poly1 are primitive polynomials of a preferred"
	    " pair of m-sequences.\n" );
    fprintf(stderr, " Try, for example,\n" );
    fprintf(stderr, "   %s 6 0103 0147\n", argv[0] );
    fprintf(stderr, "   %s 18 01000201 01002241\n", argv[0] );
    /*    fprintf(stderr, "   %s 36 01000000004001\n", argv[0] ); */
    exit(1);
  }

  deg = atoi( argv[1] );
  if ( deg < 4 ) {
    fprintf(stderr, "deg should be greater than 4\n");
    exit(1);
  }

  strncpy( poly0, argv[2], SZ_BUF );
  strncpy( poly1, argv[3], SZ_BUF );

  poly2 = find_longsubpoly( deg, poly1 );

  /* Print the header. */
  printf("The entered long Kasami code specification is\n\n");
  printf("  degree      : %d\n", deg);
  printf("  poly0(octal): %s\n",   poly0 );
  printf("  poly1(octal): %s\n",   poly1 );
  printf("  poly2(octal): 0%lo\n\n", poly2 );
  printf("This program generates two eKasami sequences using "
	 "the above polynomials.\n"
	 "The seeds for the first  Kasami sequence are '1', '1' and '1'.\n"
	 "The seeds for the second Kasami sequence are '1', '2' and '5'.\n");
  printf("\n1st column: offset in hexadecimal format\n");
  printf("2nd column: autocorrelations of the first  eKasami sequence\n");
  printf("3rd column: autocorrelations of the second eKasami sequence\n");
  printf("4th column: cross-correlations between the two Kasami sequences\n");
  puts("");
  
  pn_size.h = 0; pn_size.l = 1;
  u2long_lshift( &pn_size, deg );
  u2long_dec( &pn_size );

  pn00 = ekasami_create( deg, poly0, poly1, one, one, 0 );
  pn01 = ekasami_create( deg, poly0, poly1, one, one, 0 );
  pn10 = ekasami_create( deg, poly0, poly1, one, two, 1 );
  pn11 = ekasami_create( deg, poly0, poly1, one, two, 1 );

  for ( offset.h = 0, offset.l = 0; u2long_cmp(offset,pn_size) < 0;
	u2long_inc(&offset) ) { 
    u2long i;
    u2long acorr0, acorr1, xcorr;
    char c0, c1;

    acorr0.h = acorr1.h = xcorr.h = 0;
    acorr0.l = acorr1.l = xcorr.l = 0;
    for ( i.h=0, i.l=0; u2long_cmp(i,pn_size) < 0; u2long_inc(&i) ) {
      if( (c0=ekasami(pn00)) == ekasami(pn01) )  u2long_inc(&acorr0);
      else  u2long_dec(&acorr0);
      if( ekasami(pn10) == (c1=ekasami(pn11)) )  u2long_inc(&acorr1);
      else  u2long_dec(&acorr1);
      if( c0 == c1 ) u2long_inc(&xcorr );
      else u2long_dec(&xcorr );
    }

    printf("%08lx:%08lx %10ld %10ld %10ld\n", offset.h, offset.l,
	   acorr0.l, acorr1.l, xcorr.l );

    /* increment the offset. */
    ekasami(pn01);
    ekasami(pn11);

  }
  puts("");

  ekasami_free(pn00);    ekasami_free(pn01);
  ekasami_free(pn10);    ekasami_free(pn11);

  return 0;
}