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			1288 lines
		
	
	
		
			45 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			1288 lines
		
	
	
		
			45 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
 | |
|  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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|  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 "jelinek.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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| 
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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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| fftwf_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, float *idat, float *qdat,
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|                          double *freq, int *wspr_type)
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| {
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|     float *buffer;
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|     double dfreq;
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|     int i,ntrmin;
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|     char *c2file[15];
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|     FILE* fp;
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|     
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|     buffer=malloc(sizeof(float)*2*65536);
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|     memset(buffer,0,sizeof(float)*2*65536);
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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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|     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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|     }
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|     
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|     if( nread == 2*45000 ) {
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|         return nread/2;
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|     } else {
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|         return 1;
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|     }
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|     free(buffer);
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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, float *idat, float *qdat )
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| {
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|     size_t i, j, npoints;
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|     int nfft1, nfft2, nh2, i0;
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|     double df;
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|     
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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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|     
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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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|     
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|     float *realin;
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|     fftwf_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=(float*) fftwf_malloc(sizeof(float)*nfft1);
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|     fftout=(fftwf_complex*) fftwf_malloc(sizeof(fftwf_complex)*nfft1);
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|     PLAN1 = fftwf_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<(size_t)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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|     fftwf_execute(PLAN1);
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|     fftwf_free(realin);
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|     
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|     fftin=(fftwf_complex*) fftwf_malloc(sizeof(fftwf_complex)*nfft2);
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|     
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|     for (i=0; i<(size_t)nfft2; i++) {
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|         j=i0+i;
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|         if( i>(size_t)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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|     fftwf_free(fftout);
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|     fftout=(fftwf_complex*) fftwf_malloc(sizeof(fftwf_complex)*nfft2);
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|     PLAN2 = fftwf_plan_dft_1d(nfft2, fftin, fftout, FFTW_BACKWARD, PATIENCE);
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|     fftwf_execute(PLAN2);
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|     
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|     for (i=0; i<(size_t)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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|     fftwf_free(fftin);
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|     fftwf_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(float *id, float *qd, long np,
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|                          unsigned char *symbols, float *f1, int ifmin, int ifmax, 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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|     static float fplast=-10000.0;
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|     static float dt=1.0/375.0, df=375.0/256.0;
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|     static float pi=3.14159265358979323846;
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|     float twopidt, df15=df*1.5, df05=df*0.5;
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| 
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|     int i, j, k, lag;
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|     float i0[162],q0[162],i1[162],q1[162],i2[162],q2[162],i3[162],q3[162];
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|     float p0,p1,p2,p3,cmet,totp,syncmax,fac;
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|     float c0[256],s0[256],c1[256],s1[256],c2[256],s2[256],c3[256],s3[256];
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|     float dphi0, cdphi0, sdphi0, dphi1, cdphi1, sdphi1, dphi2, cdphi2, sdphi2,
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|     dphi3, cdphi3, sdphi3;
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|     float f0=0.0, fp, ss, fbest=0.0, fsum=0.0, f2sum=0.0, fsymb[162];
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|     int best_shift = 0, ifreq;
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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;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++) {
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|         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 + (*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-df15);
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|                     cdphi0=cos(dphi0);
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|                     sdphi0=sin(dphi0);
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|                     
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|                     dphi1=twopidt*(fp-df05);
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|                     cdphi1=cos(dphi1);
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|                     sdphi1=sin(dphi1);
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|                     
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|                     dphi2=twopidt*(fp+df05);
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|                     cdphi2=cos(dphi2);
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|                     sdphi2=sin(dphi2);
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|                     
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|                     dphi3=twopidt*(fp+df15);
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|                     cdphi3=cos(dphi3);
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|                     sdphi3=sin(dphi3);
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|                     
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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;
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|                     
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|                     for (j=1; j<256; j++) {
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|                         c0[j]=c0[j-1]*cdphi0 - s0[j-1]*sdphi0;
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|                         s0[j]=c0[j-1]*sdphi0 + s0[j-1]*cdphi0;
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|                         c1[j]=c1[j-1]*cdphi1 - s1[j-1]*sdphi1;
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|                         s1[j]=c1[j-1]*sdphi1 + s1[j-1]*cdphi1;
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|                         c2[j]=c2[j-1]*cdphi2 - s2[j-1]*sdphi2;
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|                         s2[j]=c2[j-1]*sdphi2 + s2[j-1]*cdphi2;
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|                         c3[j]=c3[j-1]*cdphi3 - s3[j-1]*sdphi3;
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|                         s3[j]=c3[j-1]*sdphi3 + s3[j-1]*cdphi3;
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|                     }
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|                     fplast = fp;
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|                 }
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|                 
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|                 i0[i]=0.0; q0[i]=0.0;
 | |
|                 i1[i]=0.0; q1[i]=0.0;
 | |
|                 i2[i]=0.0; q2[i]=0.0;
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|                 i3[i]=0.0; q3[i]=0.0;
 | |
|                 
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|                 for (j=0; j<256; j++) {
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|                     k=lag+i*256+j;
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|                     if( (k>0) && (k<np) ) {
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|                         i0[i]=i0[i] + id[k]*c0[j] + qd[k]*s0[j];
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|                         q0[i]=q0[i] - id[k]*s0[j] + qd[k]*c0[j];
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|                         i1[i]=i1[i] + id[k]*c1[j] + qd[k]*s1[j];
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|                         q1[i]=q1[i] - id[k]*s1[j] + qd[k]*c1[j];
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|                         i2[i]=i2[i] + id[k]*c2[j] + qd[k]*s2[j];
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|                         q2[i]=q2[i] - id[k]*s2[j] + qd[k]*c2[j];
 | |
|                         i3[i]=i3[i] + id[k]*c3[j] + qd[k]*s3[j];
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|                         q3[i]=q3[i] - id[k]*s3[j] + qd[k]*c3[j];
 | |
|                     }
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|                 }
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|                 p0=i0[i]*i0[i] + q0[i]*q0[i];
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|                 p1=i1[i]*i1[i] + q1[i]*q1[i];
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|                 p2=i2[i]*i2[i] + q2[i]*q2[i];
 | |
|                 p3=i3[i]*i3[i] + q3[i]*q3[i];
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| 
 | |
|                 p0=sqrt(p0);
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|                 p1=sqrt(p1);
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|                 p2=sqrt(p2);
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|                 p3=sqrt(p3);
 | |
|                 
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|                 totp=totp+p0+p1+p2+p3;
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|                 cmet=(p1+p3)-(p0+p2);
 | |
|                 ss = (pr3[i] == 1) ? ss+cmet : ss-cmet;
 | |
|                 if( mode == 2) {                 //Compute soft symbols
 | |
|                     if(pr3[i]==1) {
 | |
|                         fsymb[i]=p3-p1;
 | |
|                     } else {
 | |
|                         fsymb[i]=p2-p0;
 | |
|                     }
 | |
|                 }
 | |
|             }
 | |
|             ss=ss/totp;
 | |
|             if( ss > syncmax ) {          //Save best parameters
 | |
|                 syncmax=ss;
 | |
|                 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++) {
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|             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(float *id, float *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;
 | |
|     float pi=4.*atan(1.0),twopidt, fp;
 | |
|     
 | |
|     float i0,q0;
 | |
|     float c0[256],s0[256];
 | |
|     float 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(float *id, float *qd, long np,
 | |
|                       float f0, int shift0, float drift0, unsigned char* channel_symbols)
 | |
| {
 | |
|     float dt=1.0/375.0, df=375.0/256.0;
 | |
|     float 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;
 | |
|     
 | |
|     float *refi, *refq, *ci, *cq, *cfi, *cfq;
 | |
| 
 | |
|     refi=malloc(sizeof(float)*nc2);
 | |
|     refq=malloc(sizeof(float)*nc2);
 | |
|     ci=malloc(sizeof(float)*nc2);
 | |
|     cq=malloc(sizeof(float)*nc2);
 | |
|     cfi=malloc(sizeof(float)*nc2);
 | |
|     cfq=malloc(sizeof(float)*nc2);
 | |
|     
 | |
|     memset(refi,0,sizeof(float)*nc2);
 | |
|     memset(refq,0,sizeof(float)*nc2);
 | |
|     memset(ci,0,sizeof(float)*nc2);
 | |
|     memset(cq,0,sizeof(float)*nc2);
 | |
|     memset(cfi,0,sizeof(float)*nc2);
 | |
|     memset(cfq,0,sizeof(float)*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=(float)channel_symbols[i];
 | |
|         
 | |
|         dphi=twopidt*
 | |
|         (
 | |
|          f0 + (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]=cos(phi); //cannot precompute sin/cos because dphi is changing
 | |
|             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];
 | |
|         }
 | |
|     }
 | |
|     
 | |
|     //lowpass filter and remove startup transient
 | |
|     float w[nfilt], norm=0, partialsum[nfilt];
 | |
|     memset(partialsum,0,sizeof(float)*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
 | |
|                           , float *idat, float *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("       -C maximum number of decoder cycles per bit, default 10000\n");
 | |
|     printf("       -d deeper search. Slower, a few more decodes\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("       -J use the stack decoder instead of Fano decoder\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 0.45)\n");
 | |
| }
 | |
| 
 | |
| //***************************************************************************
 | |
| int main(int argc, char *argv[])
 | |
| {
 | |
|     extern char *optarg;
 | |
|     extern int optind;
 | |
|     int i,j,k;
 | |
|     unsigned char *symbols, *decdata, *channel_symbols;
 | |
|     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,more_candidates=0, stackdecoder=0;
 | |
|     int writenoise=0,usehashtable=1,wspr_type=2, ipass;
 | |
|     int writec2=0, npasses=2, subtraction=1;
 | |
|     int shift1, lagmin, lagmax, lagstep, ifmin, ifmax, worth_a_try, not_decoded;
 | |
|     unsigned int nbits=81, stacksize=200000;
 | |
|     unsigned int npoints, metric, 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;
 | |
|     double dialfreq_error=0.0;
 | |
|     float fmin=-110, fmax=110;
 | |
|     float f1, fstep, sync1, drift1;
 | |
|     float psavg[512];
 | |
|     float *idat, *qdat;
 | |
|     clock_t t0,t00;
 | |
|     float tfano=0.0,treadwav=0.0,tcandidates=0.0,tsync0=0.0;
 | |
|     float tsync1=0.0,tsync2=0.0,ttotal=0.0;
 | |
|     
 | |
|     struct result { char date[7]; char time[5]; float sync; float snr;
 | |
|                     float dt; float 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(sizeof(char)*11);
 | |
|     channel_symbols=malloc(sizeof(char)*nbits*2);
 | |
| 
 | |
|     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, ndecodes_pass=0;
 | |
|     
 | |
|     // Parameters used for performance-tuning:
 | |
|     unsigned int maxcycles=10000;            //Decoder timeout limit
 | |
|     float minsync1=0.10;                     //First sync limit
 | |
|     float minsync2=0.12;                     //Second sync limit
 | |
|     int iifac=8;                             //Step size in final DT peakup
 | |
|     int symfac=50;                           //Soft-symbol normalizing factor
 | |
|     int maxdrift=4;                          //Maximum (+/-) drift
 | |
|     float minrms=52.0 * (symfac/64.0);      //Final test for plausible decoding
 | |
|     delta=60;                                //Fano threshold step
 | |
|     float bias=0.45;                        //Fano metric bias (used for both Fano and stack algorithms)
 | |
|     
 | |
|     t00=clock();
 | |
|     fftwf_complex *fftin, *fftout;
 | |
| #include "./metric_tables.c"
 | |
|     
 | |
|     int mettab[2][256];
 | |
|     
 | |
|     idat=malloc(sizeof(float)*maxpts);
 | |
|     qdat=malloc(sizeof(float)*maxpts);
 | |
|     
 | |
|     while ( (c = getopt(argc, argv, "a:cC:de:f:HJmqstwvz:")) !=-1 ) {
 | |
|         switch (c) {
 | |
|             case 'a':
 | |
|                 data_dir = optarg;
 | |
|                 break;
 | |
|             case 'c':
 | |
|                 writec2=1;
 | |
|                 break;
 | |
|             case 'C':
 | |
|                 maxcycles=(unsigned int) strtoul(optarg,NULL,10);
 | |
|                 break;
 | |
|             case 'd':
 | |
|                 more_candidates=1;
 | |
|                 break;
 | |
|             case 'e':
 | |
|                 dialfreq_error = strtod(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 'J': //Stack (Jelinek) decoder, Fano decoder is the default
 | |
|                 stackdecoder = 1;
 | |
|                 break;
 | |
|             case 'm':  //15-minute wspr mode
 | |
|                 wspr_type = 15;
 | |
|                 break;
 | |
|             case 'q':  //no shift jittering
 | |
|                 quickmode = 1;
 | |
|                 break;
 | |
|             case 's':  //single pass mode (same as original wsprd)
 | |
|                 subtraction = 0;
 | |
|                 npasses = 1;
 | |
|                 break;
 | |
|             case 'v':
 | |
|                 verbose = 1;
 | |
|                 break;
 | |
|             case 'w':
 | |
|                 fmin=-150.0;
 | |
|                 fmax=150.0;
 | |
|                 break;
 | |
|             case 'z':
 | |
|                 bias=strtod(optarg,NULL); //fano metric bias (default is 0.45)
 | |
|                 break;
 | |
|             case '?':
 | |
|                 usage();
 | |
|                 return 1;
 | |
|         }
 | |
|     }
 | |
|     
 | |
|     if( stackdecoder ) {
 | |
|         stack=malloc(stacksize*sizeof(struct snode));
 | |
|     }
 | |
|     
 | |
|     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_fftwf_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_fftwf_wisdom_file = fopen(wisdom_fname, "r"))) {  //Open FFTW wisdom
 | |
|         fftwf_import_wisdom_from_file(fp_fftwf_wisdom_file);
 | |
|         fclose(fp_fftwf_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,"%f %f %f %f %f %f %f",
 | |
|                   &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 += (float)(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=(fftwf_complex*) fftwf_malloc(sizeof(fftwf_complex)*512);
 | |
|     fftout=(fftwf_complex*) fftwf_malloc(sizeof(fftwf_complex)*512);
 | |
|     PLAN3 = fftwf_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 > 0 && ndecodes_pass == 0 ) break;
 | |
|         ndecodes_pass=0;
 | |
|         
 | |
|         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];
 | |
|             }
 | |
|             fftwf_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*min_snr;
 | |
|             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;
 | |
|         unsigned char candidate;
 | |
|         if( more_candidates ) {
 | |
|             for(j=0; j<411; j=j+2) {
 | |
|                 candidate = (smspec[j]>min_snr) && (npk<200);
 | |
|                 if ( candidate ) {
 | |
|                     freq0[npk]=(j-205)*df;
 | |
|                     snr0[npk]=10*log10(smspec[j])-snr_scaling_factor;
 | |
|                     npk++;
 | |
|                 }
 | |
|             }
 | |
|         } else {
 | |
|             for(j=1; j<410; j++) {
 | |
|                 candidate = (smspec[j]>smspec[j-1]) &&
 | |
|                             (smspec[j]>smspec[j+1]) &&
 | |
|                             (npk<200);
 | |
|                 if ( candidate ) {
 | |
|                     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=if0-2; ifr<=if0+2; 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 += (float)(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];
 | |
| 
 | |
|             
 | |
|             // coarse-grid lag and freq search, then if sync>minsync1 continue
 | |
|             fstep=0.0; ifmin=0; ifmax=0;
 | |
|             lagmin=shift1-128;
 | |
|             lagmax=shift1+128;
 | |
|             lagstep=64;
 | |
|             t0 = clock();
 | |
|             sync_and_demodulate(idat, qdat, npoints, symbols, &f1, ifmin, ifmax, fstep, &shift1,
 | |
|                                 lagmin, lagmax, lagstep, &drift1, symfac, &sync1, 0);
 | |
|             tsync0 += (float)(clock()-t0)/CLOCKS_PER_SEC;
 | |
| 
 | |
|             fstep=0.25; ifmin=-2; ifmax=2;
 | |
|             t0 = clock();
 | |
|             sync_and_demodulate(idat, qdat, npoints, symbols, &f1, ifmin, ifmax, fstep, &shift1,
 | |
|                                 lagmin, lagmax, lagstep, &drift1, symfac, &sync1, 1);
 | |
| 
 | |
|             // refine drift estimate
 | |
|             fstep=0.0; ifmin=0; ifmax=0;
 | |
|             float driftp,driftm,syncp,syncm;
 | |
|             driftp=drift1+0.5;
 | |
|             sync_and_demodulate(idat, qdat, npoints, symbols, &f1, ifmin, ifmax, fstep, &shift1,
 | |
|                                 lagmin, lagmax, lagstep, &driftp, symfac, &syncp, 1);
 | |
|             
 | |
|             driftm=drift1-0.5;
 | |
|             sync_and_demodulate(idat, qdat, npoints, symbols, &f1, ifmin, ifmax, fstep, &shift1,
 | |
|                                 lagmin, lagmax, lagstep, &driftm, symfac, &syncm, 1);
 | |
|             
 | |
|             if(syncp>sync1) {
 | |
|                 drift1=driftp;
 | |
|                 sync1=syncp;
 | |
|             } else if (syncm>sync1) {
 | |
|                 drift1=driftm;
 | |
|                 sync1=syncm;
 | |
|             }
 | |
| 
 | |
|             tsync1 += (float)(clock()-t0)/CLOCKS_PER_SEC;
 | |
| 
 | |
|             // fine-grid lag and freq search
 | |
|             if( sync1 > minsync1 ) {
 | |
|         
 | |
|                 lagmin=shift1-32; lagmax=shift1+32; lagstep=16;
 | |
|                 t0 = clock();
 | |
|                 sync_and_demodulate(idat, qdat, npoints, symbols, &f1, ifmin, ifmax, fstep, &shift1,
 | |
|                                     lagmin, lagmax, lagstep, &drift1, symfac, &sync1, 0);
 | |
|                 tsync0 += (float)(clock()-t0)/CLOCKS_PER_SEC;
 | |
|             
 | |
|                 // fine search over frequency
 | |
|                 fstep=0.05; ifmin=-2; ifmax=2;
 | |
|                 t0 = clock();
 | |
|                 sync_and_demodulate(idat, qdat, npoints, symbols, &f1, ifmin, ifmax, fstep, &shift1,
 | |
|                                 lagmin, lagmax, lagstep, &drift1, symfac, &sync1, 1);
 | |
|                 tsync1 += (float)(clock()-t0)/CLOCKS_PER_SEC;
 | |
| 
 | |
|                 worth_a_try = 1;
 | |
|             } else {
 | |
|                 worth_a_try = 0;
 | |
|             }
 | |
|             
 | |
|             int idt=0, ii=0, jiggered_shift;
 | |
|             float 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, ifmin, ifmax, fstep,
 | |
|                                     &jiggered_shift, lagmin, lagmax, lagstep, &drift1, symfac,
 | |
|                                     &sync1, 2);
 | |
|                 tsync2 += (float)(clock()-t0)/CLOCKS_PER_SEC;
 | |
| 
 | |
|                 sq=0.0;
 | |
|                 for(i=0; i<162; i++) {
 | |
|                     y=(float)symbols[i] - 128.0;
 | |
|                     sq += y*y;
 | |
|                 }
 | |
|                 rms=sqrt(sq/162.0);
 | |
| 
 | |
|                 if((sync1 > minsync2) && (rms > minrms)) {
 | |
|                     deinterleave(symbols);
 | |
|                     t0 = clock();
 | |
|                     
 | |
|                     if ( stackdecoder ) {
 | |
|                         not_decoded = jelinek(&metric, &cycles, decdata, symbols, nbits,
 | |
|                                               stacksize, stack, mettab,maxcycles);
 | |
|                     } else {
 | |
|                         not_decoded = fano(&metric,&cycles,&maxnp,decdata,symbols,nbits,
 | |
|                                            mettab,delta,maxcycles);
 | |
|                     }
 | |
| 
 | |
|                     tfano += (float)(clock()-t0)/CLOCKS_PER_SEC;
 | |
|                     
 | |
|                 }
 | |
|                 idt++;
 | |
|                 if( quickmode ) break;
 | |
|             }
 | |
|             
 | |
|             if( worth_a_try && !not_decoded ) {
 | |
|                 ndecodes_pass++;
 | |
|                 
 | |
|                 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);
 | |
| 
 | |
|                 // subtract even on last pass
 | |
|                 if( subtraction && (ipass < npasses ) && !noprint ) {
 | |
|                     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-1.0;
 | |
|                     } else {
 | |
|                         freq_print=dialfreq+(1500+f1)/1e6;
 | |
|                         dt_print=shift1*dt-1.0;
 | |
|                     }
 | |
|                     
 | |
|                     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;
 | |
|                 }
 | |
|             }
 | |
|         }
 | |
|         
 | |
|         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");
 | |
|     
 | |
|     fftwf_free(fftin);
 | |
|     fftwf_free(fftout);
 | |
|     
 | |
|     if ((fp_fftwf_wisdom_file = fopen(wisdom_fname, "w"))) {
 | |
|         fftwf_export_wisdom_to_file(fp_fftwf_wisdom_file);
 | |
|         fclose(fp_fftwf_wisdom_file);
 | |
|     }
 | |
| 
 | |
|     ttotal += (float)(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,"Stack/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);
 | |
|     fftwf_destroy_plan(PLAN1);
 | |
|     fftwf_destroy_plan(PLAN2);
 | |
|     fftwf_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( stackdecoder ) {
 | |
|         free(stack);
 | |
|     }
 | |
|     
 | |
|     if(writenoise == 999) return -1;  //Silence compiler warning
 | |
|     return 0;
 | |
| }
 |