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			1229 lines
		
	
	
		
			42 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			1229 lines
		
	
	
		
			42 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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						|
 This file is part of program wsprd, a detector/demodulator/decoder
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						|
 for the Weak Signal Propagation Reporter (WSPR) mode.
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						|
 
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						|
 File name: wsprd.c
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						|
 
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						|
 Copyright 2001-2015, Joe Taylor, K1JT
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						|
 
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						|
 Much of the present code is based on work by Steven Franke, K9AN,
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						|
 which in turn was based on earlier work by K1JT.
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						|
 
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						|
 Copyright 2014-2015, Steven Franke, K9AN
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						|
 
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 License: GNU GPL v3
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						|
 
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						|
 This program is free software: you can redistribute it and/or modify
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						|
 it under the terms of the GNU General Public License as published by
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						|
 the Free Software Foundation, either version 3 of the License, or
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						|
 (at your option) any later version.
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						|
 
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						|
 This program is distributed in the hope that it will be useful,
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						|
 but WITHOUT ANY WARRANTY; without even the implied warranty of
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						|
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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						|
 GNU General Public License for more details.
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						|
 
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						|
 You should have received a copy of the GNU General Public License
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						|
 along with this program.  If not, see <http://www.gnu.org/licenses/>.
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						|
 */
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#include <stdio.h>
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						|
#include <unistd.h>
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						|
#include <stdlib.h>
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						|
#include <math.h>
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						|
#include <string.h>
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						|
#include <stdint.h>
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						|
#include <time.h>
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						|
#include <fftw3.h>
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						|
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						|
#include "fano.h"
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						|
#include "nhash.h"
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						|
#include "wsprd_utils.h"
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						|
#include "wsprsim_utils.h"
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						|
#include "lib/init_random_seed.h"
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						|
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						|
#define max(x,y) ((x) > (y) ? (x) : (y))
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						|
// Possible PATIENCE options: FFTW_ESTIMATE, FFTW_ESTIMATE_PATIENT,
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						|
// FFTW_MEASURE, FFTW_PATIENT, FFTW_EXHAUSTIVE
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						|
#define PATIENCE FFTW_ESTIMATE
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						|
fftw_plan PLAN1,PLAN2,PLAN3;
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						|
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						|
unsigned char pr3[162]=
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						|
{1,1,0,0,0,0,0,0,1,0,0,0,1,1,1,0,0,0,1,0,
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						|
    0,1,0,1,1,1,1,0,0,0,0,0,0,0,1,0,0,1,0,1,
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						|
    0,0,0,0,0,0,1,0,1,1,0,0,1,1,0,1,0,0,0,1,
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						|
    1,0,1,0,0,0,0,1,1,0,1,0,1,0,1,0,1,0,0,1,
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						|
    0,0,1,0,1,1,0,0,0,1,1,0,1,0,1,0,0,0,1,0,
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						|
    0,0,0,0,1,0,0,1,0,0,1,1,1,0,1,1,0,0,1,1,
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						|
    0,1,0,0,0,1,1,1,0,0,0,0,0,1,0,1,0,0,1,1,
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						|
    0,0,0,0,0,0,0,1,1,0,1,0,1,1,0,0,0,1,1,0,
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						|
    0,0};
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						|
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						|
unsigned long nr;
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						|
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						|
int printdata=0;
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						|
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						|
//***************************************************************************
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						|
unsigned long readc2file(char *ptr_to_infile, double *idat, double *qdat,
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						|
                         double *freq, int *wspr_type)
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						|
{
 | 
						|
    float buffer[2*65536];
 | 
						|
    double dfreq;
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						|
    int i,ntrmin;
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						|
    char *c2file[15];
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						|
    FILE* fp;
 | 
						|
    
 | 
						|
    fp = fopen(ptr_to_infile,"rb");
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						|
    if (fp == NULL) {
 | 
						|
        fprintf(stderr, "Cannot open data file '%s'\n", ptr_to_infile);
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						|
        return 1;
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						|
    }
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						|
    unsigned long nread=fread(c2file,sizeof(char),14,fp);
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						|
    nread=fread(&ntrmin,sizeof(int),1,fp);
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    nread=fread(&dfreq,sizeof(double),1,fp);
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    *freq=dfreq;
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    nread=fread(buffer,sizeof(float),2*45000,fp);
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						|
    
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    *wspr_type=ntrmin;
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						|
    
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    for(i=0; i<45000; i++) {
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        idat[i]=buffer[2*i];
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        qdat[i]=-buffer[2*i+1];
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    }
 | 
						|
    
 | 
						|
    if( nread == 2*45000 ) {
 | 
						|
        return nread/2;
 | 
						|
    } else {
 | 
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        return 1;
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    }
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						|
}
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//***************************************************************************
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						|
unsigned long readwavfile(char *ptr_to_infile, int ntrmin, double *idat, double *qdat )
 | 
						|
{
 | 
						|
    int i, j, npoints;
 | 
						|
    int nfft1, nfft2, nh2, i0;
 | 
						|
    double df;
 | 
						|
    
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    nfft2=46080; //this is the number of downsampled points that will be returned
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    nh2=nfft2/2;
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						|
    
 | 
						|
    if( ntrmin == 2 ) {
 | 
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        nfft1=nfft2*32;      //need to downsample by a factor of 32
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        df=12000.0/nfft1;
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        i0=1500.0/df+0.5;
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        npoints=114*12000;
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						|
    } else if ( ntrmin == 15 ) {
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        nfft1=nfft2*8*32;
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        df=12000.0/nfft1;
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        i0=(1500.0+112.5)/df+0.5;
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        npoints=8*114*12000;
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    } else {
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        fprintf(stderr,"This should not happen\n");
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        return 1;
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						|
    }
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    double *realin;
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						|
    fftw_complex *fftin, *fftout;
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						|
    
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    FILE *fp;
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						|
    short int *buf2;
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						|
    buf2 = malloc(npoints*sizeof(short int));
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						|
    
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						|
    fp = fopen(ptr_to_infile,"rb");
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						|
    if (fp == NULL) {
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						|
        fprintf(stderr, "Cannot open data file '%s'\n", ptr_to_infile);
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        return 1;
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						|
    }
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    nr=fread(buf2,2,22,fp);            //Read and ignore header
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						|
    nr=fread(buf2,2,npoints,fp);       //Read raw data
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    fclose(fp);
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						|
    
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    realin=(double*) fftw_malloc(sizeof(double)*nfft1);
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						|
    fftout=(fftw_complex*) fftw_malloc(sizeof(fftw_complex)*nfft1);
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    PLAN1 = fftw_plan_dft_r2c_1d(nfft1, realin, fftout, PATIENCE);
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						|
    
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    for (i=0; i<npoints; i++) {
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						|
        realin[i]=buf2[i]/32768.0;
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						|
    }
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						|
    
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    for (i=npoints; i<nfft1; i++) {
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						|
        realin[i]=0.0;
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    }
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						|
    
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						|
    free(buf2);
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						|
    fftw_execute(PLAN1);
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						|
    fftw_free(realin);
 | 
						|
    
 | 
						|
    fftin=(fftw_complex*) fftw_malloc(sizeof(fftw_complex)*nfft2);
 | 
						|
    
 | 
						|
    for (i=0; i<nfft2; i++) {
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						|
        j=i0+i;
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						|
        if( i>nh2 ) j=j-nfft2;
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						|
        fftin[i][0]=fftout[j][0];
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						|
        fftin[i][1]=fftout[j][1];
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						|
    }
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						|
    
 | 
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    fftw_free(fftout);
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						|
    fftout=(fftw_complex*) fftw_malloc(sizeof(fftw_complex)*nfft2);
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						|
    PLAN2 = fftw_plan_dft_1d(nfft2, fftin, fftout, FFTW_BACKWARD, PATIENCE);
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						|
    fftw_execute(PLAN2);
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						|
    
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						|
    for (i=0; i<nfft2; i++) {
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						|
        idat[i]=fftout[i][0]/1000.0;
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						|
        qdat[i]=fftout[i][1]/1000.0;
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						|
    }
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						|
    
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						|
    fftw_free(fftin);
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						|
    fftw_free(fftout);
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						|
    return nfft2;
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						|
}
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						|
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						|
//***************************************************************************
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						|
void sync_and_demodulate(double *id, double *qd, long np,
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						|
                         unsigned char *symbols, float *f1, float fstep,
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						|
                         int *shift1, int lagmin, int lagmax, int lagstep,
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                         float *drift1, int symfac, float *sync, int mode)
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						|
{
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						|
    /***********************************************************************
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						|
     * mode = 0: no frequency or drift search. find best time lag.          *
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						|
     *        1: no time lag or drift search. find best frequency.          *
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						|
     *        2: no frequency or time lag search. calculate soft-decision   *
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						|
     *           symbols using passed frequency and shift.                  *
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						|
     ************************************************************************/
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						|
    
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						|
    float dt=1.0/375.0, df=375.0/256.0, fbest=0.0;
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						|
    int i, j, k;
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    double pi=4.*atan(1.0),twopidt;
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						|
    float f0=0.0,fp,ss;
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						|
    int lag;
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						|
    static float fplast=-10000.0;
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						|
    double i0[162],q0[162],i1[162],q1[162],i2[162],q2[162],i3[162],q3[162];
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						|
    double p0,p1,p2,p3,cmet,totp,syncmax,fac;
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    double c0[256],s0[256],c1[256],s1[256],c2[256],s2[256],c3[256],s3[256];
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						|
    double dphi0, cdphi0, sdphi0, dphi1, cdphi1, sdphi1, dphi2, cdphi2, sdphi2,
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    dphi3, cdphi3, sdphi3;
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    float fsum=0.0, f2sum=0.0, fsymb[162];
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    int best_shift = 0, ifreq;
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						|
    int ifmin=0, ifmax=0;
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						|
    
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    syncmax=-1e30;
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						|
    if( mode == 0 ) {ifmin=0; ifmax=0; fstep=0.0; f0=*f1;}
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						|
    if( mode == 1 ) {lagmin=*shift1;lagmax=*shift1;ifmin=-5;ifmax=5;f0=*f1;}
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						|
    if( mode == 2 ) {lagmin=*shift1;lagmax=*shift1;ifmin=0;ifmax=0;f0=*f1;}
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						|
    
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    twopidt=2*pi*dt;
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						|
    for(ifreq=ifmin; ifreq<=ifmax; ifreq++) {
 | 
						|
        f0=*f1+ifreq*fstep;
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        for(lag=lagmin; lag<=lagmax; lag=lag+lagstep) {
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            ss=0.0;
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            totp=0.0;
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            for (i=0; i<162; i++) {
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                fp = f0 + ((float)*drift1/2.0)*((float)i-81.0)/81.0;
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						|
                if( i==0 || (fp != fplast) ) {  // only calculate sin/cos if necessary
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						|
                    dphi0=twopidt*(fp-1.5*df);
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						|
                    cdphi0=cos(dphi0);
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						|
                    sdphi0=sin(dphi0);
 | 
						|
                    
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                    dphi1=twopidt*(fp-0.5*df);
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						|
                    cdphi1=cos(dphi1);
 | 
						|
                    sdphi1=sin(dphi1);
 | 
						|
                    
 | 
						|
                    dphi2=twopidt*(fp+0.5*df);
 | 
						|
                    cdphi2=cos(dphi2);
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						|
                    sdphi2=sin(dphi2);
 | 
						|
                    
 | 
						|
                    dphi3=twopidt*(fp+1.5*df);
 | 
						|
                    cdphi3=cos(dphi3);
 | 
						|
                    sdphi3=sin(dphi3);
 | 
						|
                    
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						|
                    c0[0]=1; s0[0]=0;
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						|
                    c1[0]=1; s1[0]=0;
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						|
                    c2[0]=1; s2[0]=0;
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						|
                    c3[0]=1; s3[0]=0;
 | 
						|
                    
 | 
						|
                    for (j=1; j<256; j++) {
 | 
						|
                        c0[j]=c0[j-1]*cdphi0 - s0[j-1]*sdphi0;
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						|
                        s0[j]=c0[j-1]*sdphi0 + s0[j-1]*cdphi0;
 | 
						|
                        c1[j]=c1[j-1]*cdphi1 - s1[j-1]*sdphi1;
 | 
						|
                        s1[j]=c1[j-1]*sdphi1 + s1[j-1]*cdphi1;
 | 
						|
                        c2[j]=c2[j-1]*cdphi2 - s2[j-1]*sdphi2;
 | 
						|
                        s2[j]=c2[j-1]*sdphi2 + s2[j-1]*cdphi2;
 | 
						|
                        c3[j]=c3[j-1]*cdphi3 - s3[j-1]*sdphi3;
 | 
						|
                        s3[j]=c3[j-1]*sdphi3 + s3[j-1]*cdphi3;
 | 
						|
                    }
 | 
						|
                    fplast = fp;
 | 
						|
                }
 | 
						|
                
 | 
						|
                i0[i]=0.0; q0[i]=0.0;
 | 
						|
                i1[i]=0.0; q1[i]=0.0;
 | 
						|
                i2[i]=0.0; q2[i]=0.0;
 | 
						|
                i3[i]=0.0; q3[i]=0.0;
 | 
						|
                
 | 
						|
                for (j=0; j<256; j++) {
 | 
						|
                    k=lag+i*256+j;
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						|
                    if( (k>0) & (k<np) ) {
 | 
						|
                        i0[i]=i0[i] + id[k]*c0[j] + qd[k]*s0[j];
 | 
						|
                        q0[i]=q0[i] - id[k]*s0[j] + qd[k]*c0[j];
 | 
						|
                        i1[i]=i1[i] + id[k]*c1[j] + qd[k]*s1[j];
 | 
						|
                        q1[i]=q1[i] - id[k]*s1[j] + qd[k]*c1[j];
 | 
						|
                        i2[i]=i2[i] + id[k]*c2[j] + qd[k]*s2[j];
 | 
						|
                        q2[i]=q2[i] - id[k]*s2[j] + qd[k]*c2[j];
 | 
						|
                        i3[i]=i3[i] + id[k]*c3[j] + qd[k]*s3[j];
 | 
						|
                        q3[i]=q3[i] - id[k]*s3[j] + qd[k]*c3[j];
 | 
						|
                    }
 | 
						|
                }
 | 
						|
                p0=i0[i]*i0[i] + q0[i]*q0[i];
 | 
						|
                p1=i1[i]*i1[i] + q1[i]*q1[i];
 | 
						|
                p2=i2[i]*i2[i] + q2[i]*q2[i];
 | 
						|
                p3=i3[i]*i3[i] + q3[i]*q3[i];
 | 
						|
                
 | 
						|
                p0=sqrt(p0);
 | 
						|
                p1=sqrt(p1);
 | 
						|
                p2=sqrt(p2);
 | 
						|
                p3=sqrt(p3);
 | 
						|
                
 | 
						|
                totp=totp+p0+p1+p2+p3;
 | 
						|
                cmet=(p1+p3)-(p0+p2);
 | 
						|
                ss=ss+cmet*(2*pr3[i]-1);
 | 
						|
                if( mode == 2) {                 //Compute soft symbols
 | 
						|
                    if(pr3[i]) {
 | 
						|
                        fsymb[i]=p3-p1;
 | 
						|
                    } else {
 | 
						|
                        fsymb[i]=p2-p0;
 | 
						|
                    }
 | 
						|
                }
 | 
						|
            }
 | 
						|
            
 | 
						|
            if( ss/totp > syncmax ) {          //Save best parameters
 | 
						|
                syncmax=ss/totp;
 | 
						|
                best_shift=lag;
 | 
						|
                fbest=f0;
 | 
						|
            }
 | 
						|
        } // lag loop
 | 
						|
    } //freq loop
 | 
						|
    
 | 
						|
    if( mode <=1 ) {                       //Send best params back to caller
 | 
						|
        *sync=syncmax;
 | 
						|
        *shift1=best_shift;
 | 
						|
        *f1=fbest;
 | 
						|
        return;
 | 
						|
    }
 | 
						|
    
 | 
						|
    if( mode == 2 ) {
 | 
						|
        *sync=syncmax;
 | 
						|
        for (i=0; i<162; i++) {              //Normalize the soft symbols
 | 
						|
            fsum=fsum+fsymb[i]/162.0;
 | 
						|
            f2sum=f2sum+fsymb[i]*fsymb[i]/162.0;
 | 
						|
        }
 | 
						|
        fac=sqrt(f2sum-fsum*fsum);
 | 
						|
        for (i=0; i<162; i++) {
 | 
						|
            fsymb[i]=symfac*fsymb[i]/fac;
 | 
						|
            if( fsymb[i] > 127) fsymb[i]=127.0;
 | 
						|
            if( fsymb[i] < -128 ) fsymb[i]=-128.0;
 | 
						|
            symbols[i]=fsymb[i] + 128;
 | 
						|
        }
 | 
						|
        return;
 | 
						|
    }
 | 
						|
    return;
 | 
						|
}
 | 
						|
/***************************************************************************
 | 
						|
 symbol-by-symbol signal subtraction
 | 
						|
 ****************************************************************************/
 | 
						|
void subtract_signal(double *id, double *qd, long np,
 | 
						|
                     float f0, int shift0, float drift0, unsigned char* channel_symbols)
 | 
						|
{
 | 
						|
    float dt=1.0/375.0, df=375.0/256.0;
 | 
						|
    int i, j, k;
 | 
						|
    double pi=4.*atan(1.0),twopidt, fp;
 | 
						|
    
 | 
						|
    double i0,q0;
 | 
						|
    double c0[256],s0[256];
 | 
						|
    double dphi, cdphi, sdphi;
 | 
						|
    
 | 
						|
    twopidt=2*pi*dt;
 | 
						|
    
 | 
						|
    for (i=0; i<162; i++) {
 | 
						|
        fp = f0 + ((float)drift0/2.0)*((float)i-81.0)/81.0;
 | 
						|
        
 | 
						|
        dphi=twopidt*(fp+((float)channel_symbols[i]-1.5)*df);
 | 
						|
        cdphi=cos(dphi);
 | 
						|
        sdphi=sin(dphi);
 | 
						|
        
 | 
						|
        c0[0]=1; s0[0]=0;
 | 
						|
        
 | 
						|
        for (j=1; j<256; j++) {
 | 
						|
            c0[j]=c0[j-1]*cdphi - s0[j-1]*sdphi;
 | 
						|
            s0[j]=c0[j-1]*sdphi + s0[j-1]*cdphi;
 | 
						|
        }
 | 
						|
        
 | 
						|
        i0=0.0; q0=0.0;
 | 
						|
        
 | 
						|
        for (j=0; j<256; j++) {
 | 
						|
            k=shift0+i*256+j;
 | 
						|
            if( (k>0) & (k<np) ) {
 | 
						|
                i0=i0 + id[k]*c0[j] + qd[k]*s0[j];
 | 
						|
                q0=q0 - id[k]*s0[j] + qd[k]*c0[j];
 | 
						|
            }
 | 
						|
        }
 | 
						|
        
 | 
						|
        
 | 
						|
        // subtract the signal here.
 | 
						|
        
 | 
						|
        i0=i0/256.0; //will be wrong for partial symbols at the edges...
 | 
						|
        q0=q0/256.0;
 | 
						|
        
 | 
						|
        for (j=0; j<256; j++) {
 | 
						|
            k=shift0+i*256+j;
 | 
						|
            if( (k>0) & (k<np) ) {
 | 
						|
                id[k]=id[k]- (i0*c0[j] - q0*s0[j]);
 | 
						|
                qd[k]=qd[k]- (q0*c0[j] + i0*s0[j]);
 | 
						|
            }
 | 
						|
        }
 | 
						|
    }
 | 
						|
    return;
 | 
						|
}
 | 
						|
/******************************************************************************
 | 
						|
 Fully coherent signal subtraction
 | 
						|
 *******************************************************************************/
 | 
						|
void subtract_signal2(double *id, double *qd, long np,
 | 
						|
                      float f0, int shift0, float drift0, unsigned char* channel_symbols)
 | 
						|
{
 | 
						|
    double dt=1.0/375.0, df=375.0/256.0;
 | 
						|
    double pi=4.*atan(1.0), twopidt, phi=0, dphi, cs;
 | 
						|
    int i, j, k, ii, nsym=162, nspersym=256,  nfilt=256; //nfilt must be even number.
 | 
						|
    int nsig=nsym*nspersym;
 | 
						|
    int nc2=45000;
 | 
						|
    
 | 
						|
    double *refi, *refq, *ci, *cq, *cfi, *cfq;
 | 
						|
 | 
						|
    refi=malloc(sizeof(double)*nc2);
 | 
						|
    refq=malloc(sizeof(double)*nc2);
 | 
						|
    ci=malloc(sizeof(double)*nc2);
 | 
						|
    cq=malloc(sizeof(double)*nc2);
 | 
						|
    cfi=malloc(sizeof(double)*nc2);
 | 
						|
    cfq=malloc(sizeof(double)*nc2);
 | 
						|
    
 | 
						|
    memset(refi,0,sizeof(double)*nc2);
 | 
						|
    memset(refq,0,sizeof(double)*nc2);
 | 
						|
    memset(ci,0,sizeof(double)*nc2);
 | 
						|
    memset(cq,0,sizeof(double)*nc2);
 | 
						|
    memset(cfi,0,sizeof(double)*nc2);
 | 
						|
    memset(cfq,0,sizeof(double)*nc2);
 | 
						|
    
 | 
						|
    twopidt=2.0*pi*dt;
 | 
						|
    
 | 
						|
    /******************************************************************************
 | 
						|
     Measured signal:                    s(t)=a(t)*exp( j*theta(t) )
 | 
						|
     Reference is:                       r(t) = exp( j*phi(t) )
 | 
						|
     Complex amplitude is estimated as:  c(t)=LPF[s(t)*conjugate(r(t))]
 | 
						|
     so c(t) has phase angle theta-phi
 | 
						|
     Multiply r(t) by c(t) and subtract from s(t), i.e. s'(t)=s(t)-c(t)r(t)
 | 
						|
     *******************************************************************************/
 | 
						|
    
 | 
						|
    // create reference wspr signal vector, centered on f0.
 | 
						|
    //
 | 
						|
    for (i=0; i<nsym; i++) {
 | 
						|
        
 | 
						|
        cs=(double)channel_symbols[i];
 | 
						|
        
 | 
						|
        dphi=twopidt*
 | 
						|
        (
 | 
						|
         f0 + ((float)drift0/2.0)*((float)i-(float)nsym/2.0)/((float)nsym/2.0)
 | 
						|
         + (cs-1.5)*df
 | 
						|
         );
 | 
						|
        
 | 
						|
        for ( j=0; j<nspersym; j++ ) {
 | 
						|
            ii=nspersym*i+j;
 | 
						|
            refi[ii]=refi[ii]+cos(phi); //cannot precompute sin/cos because dphi is changing
 | 
						|
            refq[ii]=refq[ii]+sin(phi);
 | 
						|
            phi=phi+dphi;
 | 
						|
        }
 | 
						|
    }
 | 
						|
    
 | 
						|
    // s(t) * conjugate(r(t))
 | 
						|
    // beginning of first symbol in reference signal is at i=0
 | 
						|
    // beginning of first symbol in received data is at shift0.
 | 
						|
    // filter transient lasts nfilt samples
 | 
						|
    // leave nfilt zeros as a pad at the beginning of the unfiltered reference signal
 | 
						|
    for (i=0; i<nsym*nspersym; i++) {
 | 
						|
        k=shift0+i;
 | 
						|
        if( (k>0) & (k<np) ) {
 | 
						|
            ci[i+nfilt] = id[k]*refi[i] + qd[k]*refq[i];
 | 
						|
            cq[i+nfilt] = qd[k]*refi[i] - id[k]*refq[i];
 | 
						|
        }
 | 
						|
    }
 | 
						|
    
 | 
						|
    //quick and dirty filter - may want to do better
 | 
						|
    double w[nfilt], norm=0, partialsum[nfilt];
 | 
						|
    memset(partialsum,0,sizeof(double)*nfilt);
 | 
						|
    for (i=0; i<nfilt; i++) {
 | 
						|
        w[i]=sin(pi*(float)i/(float)(nfilt-1));
 | 
						|
        norm=norm+w[i];
 | 
						|
    }
 | 
						|
    for (i=0; i<nfilt; i++) {
 | 
						|
        w[i]=w[i]/norm;
 | 
						|
    }
 | 
						|
    for (i=1; i<nfilt; i++) {
 | 
						|
        partialsum[i]=partialsum[i-1]+w[i];
 | 
						|
    }
 | 
						|
    
 | 
						|
    // LPF
 | 
						|
    for (i=nfilt/2; i<45000-nfilt/2; i++) {
 | 
						|
        cfi[i]=0.0; cfq[i]=0.0;
 | 
						|
        for (j=0; j<nfilt; j++) {
 | 
						|
            cfi[i]=cfi[i]+w[j]*ci[i-nfilt/2+j];
 | 
						|
            cfq[i]=cfq[i]+w[j]*cq[i-nfilt/2+j];
 | 
						|
        }
 | 
						|
    }
 | 
						|
    
 | 
						|
    // subtract c(t)*r(t) here
 | 
						|
    // (ci+j*cq)(refi+j*refq)=(ci*refi-cq*refq)+j(ci*refq)+cq*refi)
 | 
						|
    // beginning of first symbol in reference signal is at i=nfilt
 | 
						|
    // beginning of first symbol in received data is at shift0.
 | 
						|
    for (i=0; i<nsig; i++) {
 | 
						|
        if( i<nfilt/2 ) {        // take care of the end effect (LPF step response) here
 | 
						|
            norm=partialsum[nfilt/2+i];
 | 
						|
        } else if( i>(nsig-1-nfilt/2) ) {
 | 
						|
            norm=partialsum[nfilt/2+nsig-1-i];
 | 
						|
        } else {
 | 
						|
            norm=1.0;
 | 
						|
        }
 | 
						|
        k=shift0+i;
 | 
						|
        j=i+nfilt;
 | 
						|
        if( (k>0) & (k<np) ) {
 | 
						|
            id[k]=id[k] - (cfi[j]*refi[i]-cfq[j]*refq[i])/norm;
 | 
						|
            qd[k]=qd[k] - (cfi[j]*refq[i]+cfq[j]*refi[i])/norm;
 | 
						|
        }
 | 
						|
    }
 | 
						|
    
 | 
						|
    free(refi);
 | 
						|
    free(refq);
 | 
						|
    free(ci);
 | 
						|
    free(cq);
 | 
						|
    free(cfi);
 | 
						|
    free(cfq);
 | 
						|
 | 
						|
    return;
 | 
						|
}
 | 
						|
 | 
						|
unsigned long writec2file(char *c2filename, int trmin, double freq
 | 
						|
                          , double *idat, double *qdat)
 | 
						|
{
 | 
						|
    int i;
 | 
						|
    float *buffer;
 | 
						|
    buffer=malloc(sizeof(float)*2*45000);
 | 
						|
    memset(buffer,0,sizeof(float)*2*45000);
 | 
						|
    
 | 
						|
    FILE *fp;
 | 
						|
    
 | 
						|
    fp = fopen(c2filename,"wb");
 | 
						|
    if( fp == NULL ) {
 | 
						|
        fprintf(stderr, "Could not open c2 file '%s'\n", c2filename);
 | 
						|
        free(buffer);
 | 
						|
        return 0;
 | 
						|
    }
 | 
						|
    unsigned long nwrite = fwrite(c2filename,sizeof(char),14,fp);
 | 
						|
    nwrite = fwrite(&trmin, sizeof(int), 1, fp);
 | 
						|
    nwrite = fwrite(&freq, sizeof(double), 1, fp);
 | 
						|
    
 | 
						|
    for(i=0; i<45000; i++) {
 | 
						|
        buffer[2*i]=idat[i];
 | 
						|
        buffer[2*i+1]=-qdat[i];
 | 
						|
    }
 | 
						|
    
 | 
						|
    nwrite = fwrite(buffer, sizeof(float), 2*45000, fp);
 | 
						|
    if( nwrite == 2*45000 ) {
 | 
						|
        return nwrite;
 | 
						|
    } else {
 | 
						|
        free(buffer);
 | 
						|
        return 0;
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
//***************************************************************************
 | 
						|
void usage(void)
 | 
						|
{
 | 
						|
    printf("Usage: wsprd [options...] infile\n");
 | 
						|
    printf("       infile must have suffix .wav or .c2\n");
 | 
						|
    printf("\n");
 | 
						|
    printf("Options:\n");
 | 
						|
    printf("       -a <path> path to writeable data files, default=\".\"\n");
 | 
						|
    printf("       -c write .c2 file at the end of the first pass\n");
 | 
						|
    printf("       -e x (x is transceiver dial frequency error in Hz)\n");
 | 
						|
    printf("       -f x (x is transceiver dial frequency in MHz)\n");
 | 
						|
    printf("       -H do not use (or update) the hash table\n");
 | 
						|
    printf("       -m decode wspr-15 .wav file\n");
 | 
						|
    printf("       -q quick mode - doesn't dig deep for weak signals\n");
 | 
						|
    printf("       -s single pass mode, no subtraction (same as original wsprd)\n");
 | 
						|
    printf("       -v verbose mode (shows dupes)\n");
 | 
						|
    printf("       -w wideband mode - decode signals within +/- 150 Hz of center\n");
 | 
						|
    printf("       -z x (x is fano metric table bias, default is 0.42)\n");
 | 
						|
}
 | 
						|
 | 
						|
//***************************************************************************
 | 
						|
int main(int argc, char *argv[])
 | 
						|
{
 | 
						|
    extern char *optarg;
 | 
						|
    extern int optind;
 | 
						|
    int i,j,k;
 | 
						|
    unsigned char *symbols, *decdata;
 | 
						|
    signed char message[]={-9,13,-35,123,57,-39,64,0,0,0,0};
 | 
						|
    char *callsign, *call_loc_pow;
 | 
						|
    char *ptr_to_infile,*ptr_to_infile_suffix;
 | 
						|
    char *data_dir=NULL;
 | 
						|
    char wisdom_fname[200],all_fname[200],spots_fname[200];
 | 
						|
    char timer_fname[200],hash_fname[200];
 | 
						|
    char uttime[5],date[7];
 | 
						|
    int c,delta,maxpts=65536,verbose=0,quickmode=0;
 | 
						|
    int writenoise=0,usehashtable=1,wspr_type=2, ipass;
 | 
						|
    int writec2=0, npasses=2, subtraction=1;
 | 
						|
    int shift1, lagmin, lagmax, lagstep, worth_a_try, not_decoded;
 | 
						|
    unsigned int nbits=81;
 | 
						|
    unsigned int npoints, metric, maxcycles, cycles, maxnp;
 | 
						|
    float df=375.0/256.0/2;
 | 
						|
    float freq0[200],snr0[200],drift0[200],sync0[200];
 | 
						|
    int shift0[200];
 | 
						|
    float dt=1.0/375.0, dt_print;
 | 
						|
    double dialfreq_cmdline=0.0, dialfreq, freq_print;
 | 
						|
    float dialfreq_error=0.0;
 | 
						|
    float fmin=-110, fmax=110;
 | 
						|
    float f1, fstep, sync1, drift1;
 | 
						|
    float psavg[512];
 | 
						|
    double *idat, *qdat;
 | 
						|
    clock_t t0,t00;
 | 
						|
    double tfano=0.0,treadwav=0.0,tcandidates=0.0,tsync0=0.0;
 | 
						|
    double tsync1=0.0,tsync2=0.0,ttotal=0.0;
 | 
						|
    
 | 
						|
    struct result { char date[7]; char time[5]; float sync; float snr;
 | 
						|
                    float dt; double freq; char message[23]; float drift;
 | 
						|
                    unsigned int cycles; int jitter; };
 | 
						|
    struct result decodes[50];
 | 
						|
    
 | 
						|
    char *hashtab;
 | 
						|
    hashtab=malloc(sizeof(char)*32768*13);
 | 
						|
    memset(hashtab,0,sizeof(char)*32768*13);
 | 
						|
 | 
						|
    int nh;
 | 
						|
    symbols=malloc(sizeof(char)*nbits*2);
 | 
						|
    decdata=malloc((nbits+7)/8);
 | 
						|
    callsign=malloc(sizeof(char)*13);
 | 
						|
    call_loc_pow=malloc(sizeof(char)*23);
 | 
						|
    float allfreqs[100];
 | 
						|
    char allcalls[100][13];
 | 
						|
    memset(allfreqs,0,sizeof(float)*100);
 | 
						|
    memset(allcalls,0,sizeof(char)*100*13);
 | 
						|
    
 | 
						|
    int uniques=0, noprint=0;
 | 
						|
 | 
						|
    init_random_seed();
 | 
						|
 | 
						|
    // Parameters used for performance-tuning:
 | 
						|
    maxcycles=10000;                         //Fano timeout limit
 | 
						|
    double minsync1=0.10;                    //First sync limit
 | 
						|
    double minsync2=0.12;                    //Second sync limit
 | 
						|
    int iifac=3;                             //Step size in final DT peakup
 | 
						|
    int symfac=50;                           //Soft-symbol normalizing factor
 | 
						|
    int maxdrift=4;                          //Maximum (+/-) drift
 | 
						|
    double minrms=52.0 * (symfac/64.0);      //Final test for plausible decoding
 | 
						|
    delta=60;                                //Fano threshold step
 | 
						|
    
 | 
						|
    t00=clock();
 | 
						|
    fftw_complex *fftin, *fftout;
 | 
						|
#include "./metric_tables.c"
 | 
						|
    
 | 
						|
    int mettab[2][256];
 | 
						|
    float bias=0.42;
 | 
						|
    
 | 
						|
    idat=malloc(sizeof(double)*maxpts);
 | 
						|
    qdat=malloc(sizeof(double)*maxpts);
 | 
						|
    
 | 
						|
    while ( (c = getopt(argc, argv, "a:ce:f:Hmqstwvz:")) !=-1 ) {
 | 
						|
        switch (c) {
 | 
						|
            case 'a':
 | 
						|
                data_dir = optarg;
 | 
						|
                break;
 | 
						|
            case 'c':
 | 
						|
                writec2=1;
 | 
						|
                break;
 | 
						|
            case 'e':
 | 
						|
                dialfreq_error = strtof(optarg,NULL);   // units of Hz
 | 
						|
                // dialfreq_error = dial reading - actual, correct frequency
 | 
						|
                break;
 | 
						|
            case 'f':
 | 
						|
                dialfreq_cmdline = strtod(optarg,NULL); // units of MHz
 | 
						|
                break;
 | 
						|
            case 'H':
 | 
						|
                usehashtable = 0;
 | 
						|
                break;
 | 
						|
            case 'm':
 | 
						|
                wspr_type = 15;
 | 
						|
                break;
 | 
						|
            case 'q':
 | 
						|
                quickmode = 1;
 | 
						|
                break;
 | 
						|
            case 's':
 | 
						|
                subtraction = 0; //single pass mode (same as original wsprd)
 | 
						|
                npasses = 1;
 | 
						|
                break;
 | 
						|
            case 'v':
 | 
						|
                verbose = 1;
 | 
						|
                break;
 | 
						|
            case 'w':
 | 
						|
                fmin=-150.0;
 | 
						|
                fmax=150.0;
 | 
						|
                break;
 | 
						|
            case 'z':
 | 
						|
                bias=strtof(optarg,NULL); //fano metric bias (default is 0.42)
 | 
						|
                break;
 | 
						|
            case '?':
 | 
						|
                usage();
 | 
						|
                return 1;
 | 
						|
        }
 | 
						|
    }
 | 
						|
    
 | 
						|
    if( optind+1 > argc) {
 | 
						|
        usage();
 | 
						|
        return 1;
 | 
						|
    } else {
 | 
						|
        ptr_to_infile=argv[optind];
 | 
						|
    }
 | 
						|
    
 | 
						|
    // setup metric table
 | 
						|
    for(i=0; i<256; i++) {
 | 
						|
        mettab[0][i]=round( 10*(metric_tables[2][i]-bias) );
 | 
						|
        mettab[1][i]=round( 10*(metric_tables[2][255-i]-bias) );
 | 
						|
    }
 | 
						|
    
 | 
						|
    FILE *fp_fftw_wisdom_file, *fall_wspr, *fwsprd, *fhash, *ftimer;
 | 
						|
    strcpy(wisdom_fname,".");
 | 
						|
    strcpy(all_fname,".");
 | 
						|
    strcpy(spots_fname,".");
 | 
						|
    strcpy(timer_fname,".");
 | 
						|
    strcpy(hash_fname,".");
 | 
						|
    if(data_dir != NULL) {
 | 
						|
        strcpy(wisdom_fname,data_dir);
 | 
						|
        strcpy(all_fname,data_dir);
 | 
						|
        strcpy(spots_fname,data_dir);
 | 
						|
        strcpy(timer_fname,data_dir);
 | 
						|
        strcpy(hash_fname,data_dir);
 | 
						|
    }
 | 
						|
    strncat(wisdom_fname,"/wspr_wisdom.dat",20);
 | 
						|
    strncat(all_fname,"/ALL_WSPR.TXT",20);
 | 
						|
    strncat(spots_fname,"/wspr_spots.txt",20);
 | 
						|
    strncat(timer_fname,"/wspr_timer.out",20);
 | 
						|
    strncat(hash_fname,"/hashtable.txt",20);
 | 
						|
    if ((fp_fftw_wisdom_file = fopen(wisdom_fname, "r"))) {  //Open FFTW wisdom
 | 
						|
        fftw_import_wisdom_from_file(fp_fftw_wisdom_file);
 | 
						|
        fclose(fp_fftw_wisdom_file);
 | 
						|
    }
 | 
						|
    
 | 
						|
    fall_wspr=fopen(all_fname,"a");
 | 
						|
    fwsprd=fopen(spots_fname,"w");
 | 
						|
    //  FILE *fdiag;
 | 
						|
    //  fdiag=fopen("wsprd_diag","a");
 | 
						|
    
 | 
						|
    if((ftimer=fopen(timer_fname,"r"))) {
 | 
						|
        //Accumulate timing data
 | 
						|
        nr=fscanf(ftimer,"%lf %lf %lf %lf %lf %lf %lf",
 | 
						|
                  &treadwav,&tcandidates,&tsync0,&tsync1,&tsync2,&tfano,&ttotal);
 | 
						|
        fclose(ftimer);
 | 
						|
    }
 | 
						|
    ftimer=fopen(timer_fname,"w");
 | 
						|
    
 | 
						|
    if( strstr(ptr_to_infile,".wav") ) {
 | 
						|
        ptr_to_infile_suffix=strstr(ptr_to_infile,".wav");
 | 
						|
        
 | 
						|
        t0 = clock();
 | 
						|
        npoints=readwavfile(ptr_to_infile, wspr_type, idat, qdat);
 | 
						|
        treadwav += (double)(clock()-t0)/CLOCKS_PER_SEC;
 | 
						|
        
 | 
						|
        if( npoints == 1 ) {
 | 
						|
            return 1;
 | 
						|
        }
 | 
						|
        dialfreq=dialfreq_cmdline - (dialfreq_error*1.0e-06);
 | 
						|
    } else if ( strstr(ptr_to_infile,".c2") !=0 )  {
 | 
						|
        ptr_to_infile_suffix=strstr(ptr_to_infile,".c2");
 | 
						|
        npoints=readc2file(ptr_to_infile, idat, qdat, &dialfreq, &wspr_type);
 | 
						|
        if( npoints == 1 ) {
 | 
						|
            return 1;
 | 
						|
        }
 | 
						|
        dialfreq -= (dialfreq_error*1.0e-06);
 | 
						|
    } else {
 | 
						|
        printf("Error: Failed to open %s\n",ptr_to_infile);
 | 
						|
        printf("WSPR file must have suffix .wav or .c2\n");
 | 
						|
        return 1;
 | 
						|
    }
 | 
						|
    
 | 
						|
    // Parse date and time from given filename
 | 
						|
    strncpy(date,ptr_to_infile_suffix-11,6);
 | 
						|
    strncpy(uttime,ptr_to_infile_suffix-4,4);
 | 
						|
    date[6]='\0';
 | 
						|
    uttime[4]='\0';
 | 
						|
    
 | 
						|
    // Do windowed ffts over 2 symbols, stepped by half symbols
 | 
						|
    int nffts=4*floor(npoints/512)-1;
 | 
						|
    fftin=(fftw_complex*) fftw_malloc(sizeof(fftw_complex)*512);
 | 
						|
    fftout=(fftw_complex*) fftw_malloc(sizeof(fftw_complex)*512);
 | 
						|
    PLAN3 = fftw_plan_dft_1d(512, fftin, fftout, FFTW_FORWARD, PATIENCE);
 | 
						|
    
 | 
						|
    float ps[512][nffts];
 | 
						|
    float w[512];
 | 
						|
    for(i=0; i<512; i++) {
 | 
						|
        w[i]=sin(0.006147931*i);
 | 
						|
    }
 | 
						|
    
 | 
						|
    if( usehashtable ) {
 | 
						|
        char line[80], hcall[12];
 | 
						|
        if( (fhash=fopen(hash_fname,"r+")) ) {
 | 
						|
            while (fgets(line, sizeof(line), fhash) != NULL) {
 | 
						|
                sscanf(line,"%d %s",&nh,hcall);
 | 
						|
                strcpy(hashtab+nh*13,hcall);
 | 
						|
            }
 | 
						|
        } else {
 | 
						|
            fhash=fopen(hash_fname,"w+");
 | 
						|
        }
 | 
						|
        fclose(fhash);
 | 
						|
    }
 | 
						|
    
 | 
						|
    //*************** main loop starts here *****************
 | 
						|
    for (ipass=0; ipass<npasses; ipass++) {
 | 
						|
        
 | 
						|
        if( ipass == 1 && uniques == 0 ) break;
 | 
						|
        if( ipass == 1 ) {  //otherwise we bog down on the second pass
 | 
						|
            quickmode = 1;
 | 
						|
        }
 | 
						|
        
 | 
						|
        memset(ps,0.0, sizeof(float)*512*nffts);
 | 
						|
        for (i=0; i<nffts; i++) {
 | 
						|
            for(j=0; j<512; j++ ) {
 | 
						|
                k=i*128+j;
 | 
						|
                fftin[j][0]=idat[k] * w[j];
 | 
						|
                fftin[j][1]=qdat[k] * w[j];
 | 
						|
            }
 | 
						|
            fftw_execute(PLAN3);
 | 
						|
            for (j=0; j<512; j++ ) {
 | 
						|
                k=j+256;
 | 
						|
                if( k>511 )
 | 
						|
                    k=k-512;
 | 
						|
                ps[j][i]=fftout[k][0]*fftout[k][0]+fftout[k][1]*fftout[k][1];
 | 
						|
            }
 | 
						|
        }
 | 
						|
        
 | 
						|
        // Compute average spectrum
 | 
						|
        memset(psavg,0.0, sizeof(float)*512);
 | 
						|
        for (i=0; i<nffts; i++) {
 | 
						|
            for (j=0; j<512; j++) {
 | 
						|
                psavg[j]=psavg[j]+ps[j][i];
 | 
						|
            }
 | 
						|
        }
 | 
						|
        
 | 
						|
        // Smooth with 7-point window and limit spectrum to +/-150 Hz
 | 
						|
        int window[7]={1,1,1,1,1,1,1};
 | 
						|
        float smspec[411];
 | 
						|
        for (i=0; i<411; i++) {
 | 
						|
            smspec[i]=0.0;
 | 
						|
            for(j=-3; j<=3; j++) {
 | 
						|
                k=256-205+i+j;
 | 
						|
                smspec[i]=smspec[i]+window[j+3]*psavg[k];
 | 
						|
            }
 | 
						|
        }
 | 
						|
        
 | 
						|
        // Sort spectrum values, then pick off noise level as a percentile
 | 
						|
        float tmpsort[411];
 | 
						|
        for (j=0; j<411; j++) {
 | 
						|
            tmpsort[j]=smspec[j];
 | 
						|
        }
 | 
						|
        qsort(tmpsort, 411, sizeof(float), floatcomp);
 | 
						|
        
 | 
						|
        // Noise level of spectrum is estimated as 123/411= 30'th percentile
 | 
						|
        float noise_level = tmpsort[122];
 | 
						|
        
 | 
						|
        /* Renormalize spectrum so that (large) peaks represent an estimate of snr.
 | 
						|
         * We know from experience that threshold snr is near -7dB in wspr bandwidth,
 | 
						|
         * corresponding to -7-26.3=-33.3dB in 2500 Hz bandwidth.
 | 
						|
         * The corresponding threshold is -42.3 dB in 2500 Hz bandwidth for WSPR-15. */
 | 
						|
        
 | 
						|
        float min_snr, snr_scaling_factor;
 | 
						|
        min_snr = pow(10.0,-7.0/10.0); //this is min snr in wspr bw
 | 
						|
        if( wspr_type == 2 ) {
 | 
						|
            snr_scaling_factor=26.3;
 | 
						|
        } else {
 | 
						|
            snr_scaling_factor=35.3;
 | 
						|
        }
 | 
						|
        for (j=0; j<411; j++) {
 | 
						|
            smspec[j]=smspec[j]/noise_level - 1.0;
 | 
						|
            if( smspec[j] < min_snr) smspec[j]=0.1;
 | 
						|
            continue;
 | 
						|
        }
 | 
						|
        
 | 
						|
        // Find all local maxima in smoothed spectrum.
 | 
						|
        for (i=0; i<200; i++) {
 | 
						|
            freq0[i]=0.0;
 | 
						|
            snr0[i]=0.0;
 | 
						|
            drift0[i]=0.0;
 | 
						|
            shift0[i]=0;
 | 
						|
            sync0[i]=0.0;
 | 
						|
        }
 | 
						|
        
 | 
						|
        int npk=0;
 | 
						|
        for(j=1; j<410; j++) {
 | 
						|
            if((smspec[j]>smspec[j-1]) && (smspec[j]>smspec[j+1]) && (npk<200)) {
 | 
						|
                freq0[npk]=(j-205)*df;
 | 
						|
                snr0[npk]=10*log10(smspec[j])-snr_scaling_factor;
 | 
						|
                npk++;
 | 
						|
            }
 | 
						|
        }
 | 
						|
        
 | 
						|
        // Compute corrected fmin, fmax, accounting for dial frequency error
 | 
						|
        fmin += dialfreq_error;    // dialfreq_error is in units of Hz
 | 
						|
        fmax += dialfreq_error;
 | 
						|
        
 | 
						|
        // Don't waste time on signals outside of the range [fmin,fmax].
 | 
						|
        i=0;
 | 
						|
        for( j=0; j<npk; j++) {
 | 
						|
            if( freq0[j] >= fmin && freq0[j] <= fmax ) {
 | 
						|
                freq0[i]=freq0[j];
 | 
						|
                snr0[i]=snr0[j];
 | 
						|
                i++;
 | 
						|
            }
 | 
						|
        }
 | 
						|
        npk=i;
 | 
						|
        
 | 
						|
        // bubble sort on snr, bringing freq along for the ride
 | 
						|
        int pass;
 | 
						|
        float tmp;
 | 
						|
        for (pass = 1; pass <= npk - 1; pass++) {
 | 
						|
            for (k = 0; k < npk - pass ; k++) {
 | 
						|
                if (snr0[k] < snr0[k+1]) {
 | 
						|
                    tmp = snr0[k];
 | 
						|
                    snr0[k] = snr0[k+1];
 | 
						|
                    snr0[k+1] = tmp;
 | 
						|
                    tmp = freq0[k];
 | 
						|
                    freq0[k] = freq0[k+1];
 | 
						|
                    freq0[k+1] = tmp;
 | 
						|
                }
 | 
						|
            }
 | 
						|
        }
 | 
						|
        
 | 
						|
        t0=clock();
 | 
						|
        /* Make coarse estimates of shift (DT), freq, and drift
 | 
						|
         
 | 
						|
         * Look for time offsets up to +/- 8 symbols (about +/- 5.4 s) relative
 | 
						|
         to nominal start time, which is 2 seconds into the file
 | 
						|
         
 | 
						|
         * Calculates shift relative to the beginning of the file
 | 
						|
         
 | 
						|
         * Negative shifts mean that signal started before start of file
 | 
						|
         
 | 
						|
         * The program prints DT = shift-2 s
 | 
						|
         
 | 
						|
         * Shifts that cause sync vector to fall off of either end of the data
 | 
						|
         vector are accommodated by "partial decoding", such that missing
 | 
						|
         symbols produce a soft-decision symbol value of 128
 | 
						|
         
 | 
						|
         * The frequency drift model is linear, deviation of +/- drift/2 over the
 | 
						|
         span of 162 symbols, with deviation equal to 0 at the center of the
 | 
						|
         signal vector.
 | 
						|
         */
 | 
						|
        
 | 
						|
        int idrift,ifr,if0,ifd,k0;
 | 
						|
        int kindex;
 | 
						|
        float smax,ss,pow,p0,p1,p2,p3;
 | 
						|
        for(j=0; j<npk; j++) {                              //For each candidate...
 | 
						|
            smax=-1e30;
 | 
						|
            if0=freq0[j]/df+256;
 | 
						|
            for (ifr=if0-1; ifr<=if0+1; ifr++) {                      //Freq search
 | 
						|
                for( k0=-10; k0<22; k0++) {                             //Time search
 | 
						|
                    for (idrift=-maxdrift; idrift<=maxdrift; idrift++) {  //Drift search
 | 
						|
                        ss=0.0;
 | 
						|
                        pow=0.0;
 | 
						|
                        for (k=0; k<162; k++) {                             //Sum over symbols
 | 
						|
                            ifd=ifr+((float)k-81.0)/81.0*( (float)idrift )/(2.0*df);
 | 
						|
                            kindex=k0+2*k;
 | 
						|
                            if( kindex < nffts ) {
 | 
						|
                                p0=ps[ifd-3][kindex];
 | 
						|
                                p1=ps[ifd-1][kindex];
 | 
						|
                                p2=ps[ifd+1][kindex];
 | 
						|
                                p3=ps[ifd+3][kindex];
 | 
						|
                                
 | 
						|
                                p0=sqrt(p0);
 | 
						|
                                p1=sqrt(p1);
 | 
						|
                                p2=sqrt(p2);
 | 
						|
                                p3=sqrt(p3);
 | 
						|
                                
 | 
						|
                                ss=ss+(2*pr3[k]-1)*((p1+p3)-(p0+p2));
 | 
						|
                                pow=pow+p0+p1+p2+p3;
 | 
						|
                                sync1=ss/pow;
 | 
						|
                            }
 | 
						|
                        }
 | 
						|
                        if( sync1 > smax ) {                  //Save coarse parameters
 | 
						|
                            smax=sync1;
 | 
						|
                            shift0[j]=128*(k0+1);
 | 
						|
                            drift0[j]=idrift;
 | 
						|
                            freq0[j]=(ifr-256)*df;
 | 
						|
                            sync0[j]=sync1;
 | 
						|
                        }
 | 
						|
                    }
 | 
						|
                }
 | 
						|
            }
 | 
						|
        }
 | 
						|
        tcandidates += (double)(clock()-t0)/CLOCKS_PER_SEC;
 | 
						|
        
 | 
						|
        /*
 | 
						|
         Refine the estimates of freq, shift using sync as a metric.
 | 
						|
         Sync is calculated such that it is a float taking values in the range
 | 
						|
         [0.0,1.0].
 | 
						|
         
 | 
						|
         Function sync_and_demodulate has three modes of operation
 | 
						|
         mode is the last argument:
 | 
						|
         
 | 
						|
         0 = no frequency or drift search. find best time lag.
 | 
						|
         1 = no time lag or drift search. find best frequency.
 | 
						|
         2 = no frequency or time lag search. Calculate soft-decision
 | 
						|
         symbols using passed frequency and shift.
 | 
						|
         
 | 
						|
         NB: best possibility for OpenMP may be here: several worker threads
 | 
						|
         could each work on one candidate at a time.
 | 
						|
         */
 | 
						|
        
 | 
						|
        for (j=0; j<npk; j++) {
 | 
						|
            memset(symbols,0,sizeof(char)*nbits*2);
 | 
						|
            memset(callsign,0,sizeof(char)*13);
 | 
						|
            memset(call_loc_pow,0,sizeof(char)*23);
 | 
						|
            
 | 
						|
            f1=freq0[j];
 | 
						|
            drift1=drift0[j];
 | 
						|
            shift1=shift0[j];
 | 
						|
            sync1=sync0[j];
 | 
						|
            
 | 
						|
            // Fine search for best sync lag (mode 0)
 | 
						|
            fstep=0.0;
 | 
						|
            lagmin=shift1-144;
 | 
						|
            lagmax=shift1+144;
 | 
						|
            lagstep=8;
 | 
						|
            if(quickmode) lagstep=16;
 | 
						|
            t0 = clock();
 | 
						|
            sync_and_demodulate(idat, qdat, npoints, symbols, &f1, fstep, &shift1,
 | 
						|
                                lagmin, lagmax, lagstep, &drift1, symfac, &sync1, 0);
 | 
						|
            tsync0 += (double)(clock()-t0)/CLOCKS_PER_SEC;
 | 
						|
            
 | 
						|
            // Fine search for frequency peak (mode 1)
 | 
						|
            fstep=0.1;
 | 
						|
            t0 = clock();
 | 
						|
            sync_and_demodulate(idat, qdat, npoints, symbols, &f1, fstep, &shift1,
 | 
						|
                                lagmin, lagmax, lagstep, &drift1, symfac, &sync1, 1);
 | 
						|
            tsync1 += (double)(clock()-t0)/CLOCKS_PER_SEC;
 | 
						|
            
 | 
						|
            if( sync1 > minsync1 ) {
 | 
						|
                worth_a_try = 1;
 | 
						|
            } else {
 | 
						|
                worth_a_try = 0;
 | 
						|
            }
 | 
						|
            
 | 
						|
            int idt=0, ii=0, jiggered_shift;
 | 
						|
            double y,sq,rms;
 | 
						|
            not_decoded=1;
 | 
						|
            
 | 
						|
            while ( worth_a_try && not_decoded && idt<=(128/iifac)) {
 | 
						|
                ii=(idt+1)/2;
 | 
						|
                if( idt%2 == 1 ) ii=-ii;
 | 
						|
                ii=iifac*ii;
 | 
						|
                jiggered_shift=shift1+ii;
 | 
						|
                
 | 
						|
                // Use mode 2 to get soft-decision symbols
 | 
						|
                t0 = clock();
 | 
						|
                sync_and_demodulate(idat, qdat, npoints, symbols, &f1, fstep,
 | 
						|
                                    &jiggered_shift, lagmin, lagmax, lagstep, &drift1, symfac,
 | 
						|
                                    &sync1, 2);
 | 
						|
                tsync2 += (double)(clock()-t0)/CLOCKS_PER_SEC;
 | 
						|
                
 | 
						|
                sq=0.0;
 | 
						|
                for(i=0; i<162; i++) {
 | 
						|
                    y=(double)symbols[i] - 128.0;
 | 
						|
                    sq += y*y;
 | 
						|
                }
 | 
						|
                rms=sqrt(sq/162.0);
 | 
						|
                
 | 
						|
                if((sync1 > minsync2) && (rms > minrms)) {
 | 
						|
                    deinterleave(symbols);
 | 
						|
                    t0 = clock();
 | 
						|
                    
 | 
						|
                    not_decoded = fano(&metric,&cycles,&maxnp,decdata,symbols,nbits,
 | 
						|
                                       mettab,delta,maxcycles);
 | 
						|
                    tfano += (double)(clock()-t0)/CLOCKS_PER_SEC;
 | 
						|
                    
 | 
						|
                    /* ### Used for timing tests:
 | 
						|
                     if(not_decoded) fprintf(fdiag,
 | 
						|
                     "%6s %4s %4.1f %3.0f %4.1f %10.7f  %-18s %2d %5u %4d %6.1f %2d\n",
 | 
						|
                     date,uttime,sync1*10,snr0[j], shift1*dt-2.0, dialfreq+(1500+f1)/1e6,
 | 
						|
                     "@                 ", (int)drift1, cycles/81, ii, rms, maxnp);
 | 
						|
                     */
 | 
						|
                }
 | 
						|
                idt++;
 | 
						|
                if( quickmode ) break;
 | 
						|
            }
 | 
						|
            
 | 
						|
            if( worth_a_try && !not_decoded ) {
 | 
						|
                
 | 
						|
                for(i=0; i<11; i++) {
 | 
						|
                    
 | 
						|
                    if( decdata[i]>127 ) {
 | 
						|
                        message[i]=decdata[i]-256;
 | 
						|
                    } else {
 | 
						|
                        message[i]=decdata[i];
 | 
						|
                    }
 | 
						|
                    
 | 
						|
                }
 | 
						|
                
 | 
						|
                // Unpack the decoded message, update the hashtable, apply
 | 
						|
                // sanity checks on grid and power, and return
 | 
						|
                // call_loc_pow string and also callsign (for de-duping).
 | 
						|
                noprint=unpk_(message,hashtab,call_loc_pow,callsign);
 | 
						|
                
 | 
						|
                if( subtraction && (ipass == 0) && !noprint ) {
 | 
						|
                    
 | 
						|
                    unsigned char channel_symbols[162];
 | 
						|
                    
 | 
						|
                    if( get_wspr_channel_symbols(call_loc_pow, hashtab, channel_symbols) ) {
 | 
						|
                        subtract_signal2(idat, qdat, npoints, f1, shift1, drift1, channel_symbols);
 | 
						|
                    } else {
 | 
						|
                        break;
 | 
						|
                    }
 | 
						|
                    
 | 
						|
                }
 | 
						|
                
 | 
						|
                // Remove dupes (same callsign and freq within 3 Hz)
 | 
						|
                int dupe=0;
 | 
						|
                for (i=0; i<uniques; i++) {
 | 
						|
                    if(!strcmp(callsign,allcalls[i]) &&
 | 
						|
                       (fabs(f1-allfreqs[i]) <3.0)) dupe=1;
 | 
						|
                }
 | 
						|
                if( (verbose || !dupe) && !noprint) {
 | 
						|
                    strcpy(allcalls[uniques],callsign);
 | 
						|
                    allfreqs[uniques]=f1;
 | 
						|
                    uniques++;
 | 
						|
                    
 | 
						|
                    // Add an extra space at the end of each line so that wspr-x doesn't
 | 
						|
                    // truncate the power (TNX to DL8FCL!)
 | 
						|
                    
 | 
						|
                    if( wspr_type == 15 ) {
 | 
						|
                        freq_print=dialfreq+(1500+112.5+f1/8.0)/1e6;
 | 
						|
                        dt_print=shift1*8*dt-2.0;
 | 
						|
                    } else {
 | 
						|
                        freq_print=dialfreq+(1500+f1)/1e6;
 | 
						|
                        dt_print=shift1*dt-2.0;
 | 
						|
                    }
 | 
						|
                    
 | 
						|
                    strcpy(decodes[uniques-1].date,date);
 | 
						|
                    strcpy(decodes[uniques-1].time,uttime);
 | 
						|
                    decodes[uniques-1].sync=sync1;
 | 
						|
                    decodes[uniques-1].snr=snr0[j];
 | 
						|
                    decodes[uniques-1].dt=dt_print;
 | 
						|
                    decodes[uniques-1].freq=freq_print;
 | 
						|
                    strcpy(decodes[uniques-1].message,call_loc_pow);
 | 
						|
                    decodes[uniques-1].drift=drift1;
 | 
						|
                    decodes[uniques-1].cycles=cycles;
 | 
						|
                    decodes[uniques-1].jitter=ii;
 | 
						|
                    
 | 
						|
                    /* For timing tests
 | 
						|
                     
 | 
						|
                     fprintf(fdiag,
 | 
						|
                     "%6s %4s %4.1f %3.0f %4.1f %10.7f  %-18s %2d %5u %4d %6.1f\n",
 | 
						|
                     date,uttime,sync1*10,snr0[j],
 | 
						|
                     shift1*dt-2.0, dialfreq+(1500+f1)/1e6,
 | 
						|
                     call_loc_pow, (int)drift1, cycles/81, ii, rms);
 | 
						|
                     */
 | 
						|
                }
 | 
						|
            }
 | 
						|
        }
 | 
						|
        
 | 
						|
        if( ipass == 0 && writec2 ) {
 | 
						|
            char c2filename[15];
 | 
						|
            double carrierfreq=dialfreq;
 | 
						|
            int wsprtype=2;
 | 
						|
            strcpy(c2filename,"000000_0001.c2");
 | 
						|
            printf("Writing %s\n",c2filename);
 | 
						|
            writec2file(c2filename, wsprtype, carrierfreq, idat, qdat);
 | 
						|
        }
 | 
						|
    }
 | 
						|
    
 | 
						|
    // sort the result in order of increasing frequency
 | 
						|
    struct result temp;
 | 
						|
    for (j = 1; j <= uniques - 1; j++) {
 | 
						|
        for (k = 0; k < uniques - j ; k++) {
 | 
						|
            if (decodes[k].freq > decodes[k+1].freq) {
 | 
						|
                temp = decodes[k];
 | 
						|
                decodes[k]=decodes[k+1];;
 | 
						|
                decodes[k+1] = temp;
 | 
						|
            }
 | 
						|
        }
 | 
						|
    }
 | 
						|
    
 | 
						|
    for (i=0; i<uniques; i++) {
 | 
						|
        printf("%4s %3.0f %4.1f %10.6f %2d  %-s \n",
 | 
						|
               decodes[i].time, decodes[i].snr,decodes[i].dt, decodes[i].freq,
 | 
						|
               (int)decodes[i].drift, decodes[i].message);
 | 
						|
        fprintf(fall_wspr,
 | 
						|
                "%6s %4s %3d %3.0f %4.1f %10.7f  %-22s %2d %5u %4d\n",
 | 
						|
                decodes[i].date, decodes[i].time, (int)(10*decodes[i].sync),
 | 
						|
                decodes[i].snr, decodes[i].dt, decodes[i].freq,
 | 
						|
                decodes[i].message, (int)decodes[i].drift, decodes[i].cycles/81,
 | 
						|
                decodes[i].jitter);
 | 
						|
        fprintf(fwsprd,
 | 
						|
                "%6s %4s %3d %3.0f %4.1f %10.6f  %-22s %2d %5u %4d\n",
 | 
						|
                decodes[i].date, decodes[i].time, (int)(10*decodes[i].sync),
 | 
						|
                decodes[i].snr, decodes[i].dt, decodes[i].freq,
 | 
						|
                decodes[i].message, (int)decodes[i].drift, decodes[i].cycles/81,
 | 
						|
                decodes[i].jitter);
 | 
						|
        
 | 
						|
    }
 | 
						|
    printf("<DecodeFinished>\n");
 | 
						|
    
 | 
						|
    fftw_free(fftin);
 | 
						|
    fftw_free(fftout);
 | 
						|
    
 | 
						|
    if ((fp_fftw_wisdom_file = fopen(wisdom_fname, "w"))) {
 | 
						|
        fftw_export_wisdom_to_file(fp_fftw_wisdom_file);
 | 
						|
        fclose(fp_fftw_wisdom_file);
 | 
						|
    }
 | 
						|
    
 | 
						|
    ttotal += (double)(clock()-t00)/CLOCKS_PER_SEC;
 | 
						|
    
 | 
						|
    fprintf(ftimer,"%7.2f %7.2f %7.2f %7.2f %7.2f %7.2f %7.2f\n\n",
 | 
						|
            treadwav,tcandidates,tsync0,tsync1,tsync2,tfano,ttotal);
 | 
						|
    
 | 
						|
    fprintf(ftimer,"Code segment        Seconds   Frac\n");
 | 
						|
    fprintf(ftimer,"-----------------------------------\n");
 | 
						|
    fprintf(ftimer,"readwavfile        %7.2f %7.2f\n",treadwav,treadwav/ttotal);
 | 
						|
    fprintf(ftimer,"Coarse DT f0 f1    %7.2f %7.2f\n",tcandidates,
 | 
						|
            tcandidates/ttotal);
 | 
						|
    fprintf(ftimer,"sync_and_demod(0)  %7.2f %7.2f\n",tsync0,tsync0/ttotal);
 | 
						|
    fprintf(ftimer,"sync_and_demod(1)  %7.2f %7.2f\n",tsync1,tsync1/ttotal);
 | 
						|
    fprintf(ftimer,"sync_and_demod(2)  %7.2f %7.2f\n",tsync2,tsync2/ttotal);
 | 
						|
    fprintf(ftimer,"Fano decoder       %7.2f %7.2f\n",tfano,tfano/ttotal);
 | 
						|
    fprintf(ftimer,"-----------------------------------\n");
 | 
						|
    fprintf(ftimer,"Total              %7.2f %7.2f\n",ttotal,1.0);
 | 
						|
    
 | 
						|
    fclose(fall_wspr);
 | 
						|
    fclose(fwsprd);
 | 
						|
    //  fclose(fdiag);
 | 
						|
    fclose(ftimer);
 | 
						|
    fftw_destroy_plan(PLAN1);
 | 
						|
    fftw_destroy_plan(PLAN2);
 | 
						|
    fftw_destroy_plan(PLAN3);
 | 
						|
    
 | 
						|
    if( usehashtable ) {
 | 
						|
        fhash=fopen(hash_fname,"w");
 | 
						|
        for (i=0; i<32768; i++) {
 | 
						|
            if( strncmp(hashtab+i*13,"\0",1) != 0 ) {
 | 
						|
                fprintf(fhash,"%5d %s\n",i,hashtab+i*13);
 | 
						|
            }
 | 
						|
        }
 | 
						|
        fclose(fhash);
 | 
						|
    }
 | 
						|
    
 | 
						|
    if(writenoise == 999) return -1;  //Silence compiler warning
 | 
						|
    return 0;
 | 
						|
}
 |