mirror of
https://github.com/saitohirga/WSJT-X.git
synced 2024-11-26 06:08:42 -05:00
1575 lines
57 KiB
C
1575 lines
57 KiB
C
/*
|
|
This file is part of program wsprd, a detector/demodulator/decoder
|
|
for the Weak Signal Propagation Reporter (WSPR) mode.
|
|
|
|
File name: wsprd.c
|
|
|
|
Copyright 2001-2018, Joe Taylor, K1JT
|
|
|
|
Much of the present code is based on work by Steven Franke, K9AN,
|
|
which in turn was based on earlier work by K1JT.
|
|
|
|
Copyright 2014-2018, Steven Franke, K9AN
|
|
|
|
License: GNU GPL v3
|
|
|
|
This program is free software: you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation, either version 3 of the License, or
|
|
(at your option) any later version.
|
|
|
|
This program is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#include <stdio.h>
|
|
#include <unistd.h>
|
|
#include <stdlib.h>
|
|
#include <math.h>
|
|
#include <string.h>
|
|
#include <stdint.h>
|
|
#include <time.h>
|
|
#include <fftw3.h>
|
|
|
|
#include "fano.h"
|
|
#include "jelinek.h"
|
|
#include "nhash.h"
|
|
#include "wsprd_utils.h"
|
|
#include "wsprsim_utils.h"
|
|
|
|
#define max(x,y) ((x) > (y) ? (x) : (y))
|
|
|
|
extern void osdwspr_ (float [], unsigned char [], int *, unsigned char [], int *, float *);
|
|
|
|
// Possible PATIENCE options: FFTW_ESTIMATE, FFTW_ESTIMATE_PATIENT,
|
|
// FFTW_MEASURE, FFTW_PATIENT, FFTW_EXHAUSTIVE
|
|
#define PATIENCE FFTW_ESTIMATE
|
|
fftwf_plan PLAN1,PLAN2,PLAN3;
|
|
|
|
unsigned char pr3[162]=
|
|
{1,1,0,0,0,0,0,0,1,0,0,0,1,1,1,0,0,0,1,0,
|
|
0,1,0,1,1,1,1,0,0,0,0,0,0,0,1,0,0,1,0,1,
|
|
0,0,0,0,0,0,1,0,1,1,0,0,1,1,0,1,0,0,0,1,
|
|
1,0,1,0,0,0,0,1,1,0,1,0,1,0,1,0,1,0,0,1,
|
|
0,0,1,0,1,1,0,0,0,1,1,0,1,0,1,0,0,0,1,0,
|
|
0,0,0,0,1,0,0,1,0,0,1,1,1,0,1,1,0,0,1,1,
|
|
0,1,0,0,0,1,1,1,0,0,0,0,0,1,0,1,0,0,1,1,
|
|
0,0,0,0,0,0,0,1,1,0,1,0,1,1,0,0,0,1,1,0,
|
|
0,0};
|
|
|
|
int printdata=0;
|
|
|
|
//***************************************************************************
|
|
unsigned long readc2file(char *ptr_to_infile, float *idat, float *qdat,
|
|
double *freq, int *wspr_type)
|
|
{
|
|
float *buffer;
|
|
double dfreq;
|
|
int i,ntrmin;
|
|
char *c2file[15];
|
|
size_t nr;
|
|
FILE* fp;
|
|
|
|
fp = fopen(ptr_to_infile,"rb");
|
|
if (fp == NULL) {
|
|
fprintf(stderr, "Cannot open data file '%s'\n", ptr_to_infile);
|
|
return 1;
|
|
}
|
|
nr=fread(c2file,sizeof(char),14,fp);
|
|
nr=fread(&ntrmin,sizeof(int),1,fp);
|
|
nr=fread(&dfreq,sizeof(double),1,fp);
|
|
*freq=dfreq;
|
|
|
|
buffer=calloc(2*65536,sizeof(float));
|
|
nr=fread(buffer,sizeof(float),2*45000,fp);
|
|
fclose(fp);
|
|
|
|
*wspr_type=ntrmin;
|
|
|
|
for(i=0; i<45000; i++) {
|
|
idat[i]=buffer[2*i];
|
|
qdat[i]=-buffer[2*i+1];
|
|
}
|
|
free(buffer);
|
|
|
|
if( nr == 2*45000 ) {
|
|
return (unsigned long) nr/2;
|
|
} else {
|
|
return 1;
|
|
}
|
|
}
|
|
|
|
//***************************************************************************
|
|
unsigned long readwavfile(char *ptr_to_infile, int ntrmin, float *idat, float *qdat )
|
|
{
|
|
size_t i, j, npoints, nr;
|
|
int nfft1, nfft2, nh2, i0;
|
|
double df;
|
|
|
|
nfft2=46080; //this is the number of downsampled points that will be returned
|
|
nh2=nfft2/2;
|
|
|
|
if( ntrmin == 2 ) {
|
|
nfft1=nfft2*32; //need to downsample by a factor of 32
|
|
df=12000.0/nfft1;
|
|
i0=1500.0/df+0.5;
|
|
npoints=114*12000;
|
|
} else if ( ntrmin == 15 ) {
|
|
nfft1=nfft2*8*32;
|
|
df=12000.0/nfft1;
|
|
i0=(1500.0+112.5)/df+0.5;
|
|
npoints=8*114*12000;
|
|
} else {
|
|
fprintf(stderr,"This should not happen\n");
|
|
return 1;
|
|
}
|
|
|
|
float *realin;
|
|
fftwf_complex *fftin, *fftout;
|
|
|
|
FILE *fp;
|
|
short int *buf2;
|
|
|
|
fp = fopen(ptr_to_infile,"rb");
|
|
if (fp == NULL) {
|
|
fprintf(stderr, "Cannot open data file '%s'\n", ptr_to_infile);
|
|
return 1;
|
|
}
|
|
|
|
buf2 = calloc(npoints,sizeof(short int));
|
|
nr=fread(buf2,2,22,fp); //Read and ignore header
|
|
nr=fread(buf2,2,npoints,fp); //Read raw data
|
|
fclose(fp);
|
|
if( nr == 0 ) {
|
|
fprintf(stderr, "No data in file '%s'\n", ptr_to_infile);
|
|
return 1;
|
|
}
|
|
|
|
realin=(float*) fftwf_malloc(sizeof(float)*nfft1);
|
|
fftout=(fftwf_complex*) fftwf_malloc(sizeof(fftwf_complex)*(nfft1/2+1));
|
|
PLAN1 = fftwf_plan_dft_r2c_1d(nfft1, realin, fftout, PATIENCE);
|
|
|
|
for (i=0; i<npoints; i++) {
|
|
realin[i]=buf2[i]/32768.0;
|
|
}
|
|
|
|
for (i=npoints; i<(size_t)nfft1; i++) {
|
|
realin[i]=0.0;
|
|
}
|
|
free(buf2);
|
|
|
|
fftwf_execute(PLAN1);
|
|
fftwf_free(realin);
|
|
|
|
fftin=(fftwf_complex*) fftwf_malloc(sizeof(fftwf_complex)*nfft2);
|
|
|
|
for (i=0; i<(size_t)nfft2; i++) {
|
|
j=i0+i;
|
|
if( i>(size_t)nh2 ) j=j-nfft2;
|
|
fftin[i][0]=fftout[j][0];
|
|
fftin[i][1]=fftout[j][1];
|
|
}
|
|
|
|
fftwf_free(fftout);
|
|
fftout=(fftwf_complex*) fftwf_malloc(sizeof(fftwf_complex)*nfft2);
|
|
PLAN2 = fftwf_plan_dft_1d(nfft2, fftin, fftout, FFTW_BACKWARD, PATIENCE);
|
|
fftwf_execute(PLAN2);
|
|
|
|
for (i=0; i<(size_t)nfft2; i++) {
|
|
idat[i]=fftout[i][0]/1000.0;
|
|
qdat[i]=fftout[i][1]/1000.0;
|
|
}
|
|
|
|
fftwf_free(fftin);
|
|
fftwf_free(fftout);
|
|
return nfft2;
|
|
}
|
|
|
|
//***************************************************************************
|
|
void sync_and_demodulate(float *id, float *qd, long np,
|
|
unsigned char *symbols, float *f1, int ifmin, int ifmax, float fstep,
|
|
int *shift1, int lagmin, int lagmax, int lagstep,
|
|
float *drift1, int symfac, float *sync, int mode)
|
|
{
|
|
/***********************************************************************
|
|
* mode = 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. *
|
|
************************************************************************/
|
|
|
|
static float fplast=-10000.0;
|
|
static float dt=1.0/375.0, df=375.0/256.0;
|
|
static float pi=3.14159265358979323846;
|
|
float twopidt, df15=df*1.5, df05=df*0.5;
|
|
|
|
int i, j, k, lag;
|
|
float i0[162],q0[162],i1[162],q1[162],i2[162],q2[162],i3[162],q3[162];
|
|
float p0,p1,p2,p3,cmet,totp,syncmax,fac;
|
|
float c0[256],s0[256],c1[256],s1[256],c2[256],s2[256],c3[256],s3[256];
|
|
float dphi0, cdphi0, sdphi0, dphi1, cdphi1, sdphi1, dphi2, cdphi2, sdphi2,
|
|
dphi3, cdphi3, sdphi3;
|
|
float f0=0.0, fp, ss, fbest=0.0, fsum=0.0, f2sum=0.0, fsymb[162];
|
|
int best_shift = 0, ifreq;
|
|
|
|
syncmax=-1e30;
|
|
if( mode == 0 ) {ifmin=0; ifmax=0; fstep=0.0; f0=*f1;}
|
|
if( mode == 1 ) {lagmin=*shift1;lagmax=*shift1;f0=*f1;}
|
|
if( mode == 2 ) {lagmin=*shift1;lagmax=*shift1;ifmin=0;ifmax=0;f0=*f1;}
|
|
|
|
twopidt=2*pi*dt;
|
|
for(ifreq=ifmin; ifreq<=ifmax; ifreq++) {
|
|
f0=*f1+ifreq*fstep;
|
|
for(lag=lagmin; lag<=lagmax; lag=lag+lagstep) {
|
|
ss=0.0;
|
|
totp=0.0;
|
|
for (i=0; i<162; i++) {
|
|
fp = f0 + (*drift1/2.0)*((float)i-81.0)/81.0;
|
|
if( i==0 || (fp != fplast) ) { // only calculate sin/cos if necessary
|
|
dphi0=twopidt*(fp-df15);
|
|
cdphi0=cos(dphi0);
|
|
sdphi0=sin(dphi0);
|
|
|
|
dphi1=twopidt*(fp-df05);
|
|
cdphi1=cos(dphi1);
|
|
sdphi1=sin(dphi1);
|
|
|
|
dphi2=twopidt*(fp+df05);
|
|
cdphi2=cos(dphi2);
|
|
sdphi2=sin(dphi2);
|
|
|
|
dphi3=twopidt*(fp+df15);
|
|
cdphi3=cos(dphi3);
|
|
sdphi3=sin(dphi3);
|
|
|
|
c0[0]=1; s0[0]=0;
|
|
c1[0]=1; s1[0]=0;
|
|
c2[0]=1; s2[0]=0;
|
|
c3[0]=1; s3[0]=0;
|
|
|
|
for (j=1; j<256; j++) {
|
|
c0[j]=c0[j-1]*cdphi0 - s0[j-1]*sdphi0;
|
|
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;
|
|
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 = (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++) {
|
|
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;
|
|
}
|
|
|
|
void noncoherent_sequence_detection(float *id, float *qd, long np,
|
|
unsigned char *symbols, float *f1, int *shift1,
|
|
float *drift1, int symfac, int *nblocksize, int *bitmetric)
|
|
{
|
|
/************************************************************************
|
|
* Noncoherent sequence detection for wspr. *
|
|
* Allowed block lengths are nblock=1,2,3,6, or 9 symbols. *
|
|
* Longer block lengths require longer channel coherence time. *
|
|
* The whole block is estimated at once. *
|
|
* nblock=1 corresponds to noncoherent detection of individual symbols *
|
|
* like the original wsprd symbol demodulator. *
|
|
************************************************************************/
|
|
static float fplast=-10000.0;
|
|
static float dt=1.0/375.0, df=375.0/256.0;
|
|
static float pi=3.14159265358979323846;
|
|
float twopidt, df15=df*1.5, df05=df*0.5;
|
|
|
|
int i, j, k, lag, itone, ib, b, nblock, nseq, imask;
|
|
float xi[512],xq[512];
|
|
float is[4][162],qs[4][162],cf[4][162],sf[4][162],cm,sm,cmp,smp;
|
|
float p[512],fac,xm1,xm0;
|
|
float c0[257],s0[257],c1[257],s1[257],c2[257],s2[257],c3[257],s3[257];
|
|
float dphi0, cdphi0, sdphi0, dphi1, cdphi1, sdphi1, dphi2, cdphi2, sdphi2,
|
|
dphi3, cdphi3, sdphi3;
|
|
float f0, fp, fsum=0.0, f2sum=0.0, fsymb[162];
|
|
|
|
twopidt=2*pi*dt;
|
|
f0=*f1;
|
|
lag=*shift1;
|
|
nblock=*nblocksize;
|
|
nseq=1<<nblock;
|
|
int bitbybit=*bitmetric;
|
|
|
|
for (i=0; i<162; i++) {
|
|
fp = f0 + (*drift1/2.0)*((float)i-81.0)/81.0;
|
|
if( i==0 || (fp != fplast) ) { // only calculate sin/cos if necessary
|
|
dphi0=twopidt*(fp-df15);
|
|
cdphi0=cos(dphi0);
|
|
sdphi0=sin(dphi0);
|
|
|
|
dphi1=twopidt*(fp-df05);
|
|
cdphi1=cos(dphi1);
|
|
sdphi1=sin(dphi1);
|
|
|
|
dphi2=twopidt*(fp+df05);
|
|
cdphi2=cos(dphi2);
|
|
sdphi2=sin(dphi2);
|
|
|
|
dphi3=twopidt*(fp+df15);
|
|
cdphi3=cos(dphi3);
|
|
sdphi3=sin(dphi3);
|
|
|
|
c0[0]=1; s0[0]=0;
|
|
c1[0]=1; s1[0]=0;
|
|
c2[0]=1; s2[0]=0;
|
|
c3[0]=1; s3[0]=0;
|
|
|
|
for (j=1; j<257; j++) {
|
|
c0[j]=c0[j-1]*cdphi0 - s0[j-1]*sdphi0;
|
|
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;
|
|
}
|
|
|
|
cf[0][i]=c0[256]; sf[0][i]=s0[256];
|
|
cf[1][i]=c1[256]; sf[1][i]=s1[256];
|
|
cf[2][i]=c2[256]; sf[2][i]=s2[256];
|
|
cf[3][i]=c3[256]; sf[3][i]=s3[256];
|
|
|
|
is[0][i]=0.0; qs[0][i]=0.0;
|
|
is[1][i]=0.0; qs[1][i]=0.0;
|
|
is[2][i]=0.0; qs[2][i]=0.0;
|
|
is[3][i]=0.0; qs[3][i]=0.0;
|
|
|
|
for (j=0; j<256; j++) {
|
|
k=lag+i*256+j;
|
|
if( (k>0) && (k<np) ) {
|
|
is[0][i]=is[0][i] + id[k]*c0[j] + qd[k]*s0[j];
|
|
qs[0][i]=qs[0][i] - id[k]*s0[j] + qd[k]*c0[j];
|
|
is[1][i]=is[1][i] + id[k]*c1[j] + qd[k]*s1[j];
|
|
qs[1][i]=qs[1][i] - id[k]*s1[j] + qd[k]*c1[j];
|
|
is[2][i]=is[2][i] + id[k]*c2[j] + qd[k]*s2[j];
|
|
qs[2][i]=qs[2][i] - id[k]*s2[j] + qd[k]*c2[j];
|
|
is[3][i]=is[3][i] + id[k]*c3[j] + qd[k]*s3[j];
|
|
qs[3][i]=qs[3][i] - id[k]*s3[j] + qd[k]*c3[j];
|
|
}
|
|
}
|
|
}
|
|
|
|
for (i=0; i<162; i=i+nblock) {
|
|
for (j=0;j<nseq;j++) {
|
|
xi[j]=0.0; xq[j]=0.0;
|
|
cm=1; sm=0;
|
|
for (ib=0; ib<nblock; ib++) {
|
|
b=(j&(1<<(nblock-1-ib)))>>(nblock-1-ib);
|
|
itone=pr3[i+ib]+2*b;
|
|
xi[j]=xi[j]+is[itone][i+ib]*cm + qs[itone][i+ib]*sm;
|
|
xq[j]=xq[j]+qs[itone][i+ib]*cm - is[itone][i+ib]*sm;
|
|
cmp=cf[itone][i+ib]*cm - sf[itone][i+ib]*sm;
|
|
smp=sf[itone][i+ib]*cm + cf[itone][i+ib]*sm;
|
|
cm=cmp; sm=smp;
|
|
}
|
|
p[j]=xi[j]*xi[j]+xq[j]*xq[j];
|
|
p[j]=sqrt(p[j]);
|
|
}
|
|
for (ib=0; ib<nblock; ib++) {
|
|
imask=1<<(nblock-1-ib);
|
|
xm1=0.0; xm0=0.0;
|
|
for (j=0; j<nseq; j++) {
|
|
if((j & imask)!=0) {
|
|
if(p[j] > xm1) xm1=p[j];
|
|
}
|
|
if((j & imask)==0) {
|
|
if(p[j]>xm0) xm0=p[j];
|
|
}
|
|
}
|
|
fsymb[i+ib]=xm1-xm0;
|
|
if( bitbybit == 1 ) {
|
|
fsymb[i+ib]=fsymb[i+ib]/(xm1 > xm0 ? xm1 : xm0);
|
|
}
|
|
}
|
|
}
|
|
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;
|
|
}
|
|
|
|
/***************************************************************************
|
|
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;
|
|
}
|
|
/******************************************************************************
|
|
Subtract the coherent component of a signal
|
|
*******************************************************************************/
|
|
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=360; //nfilt must be even number.
|
|
int nsig=nsym*nspersym;
|
|
int nc2=45000;
|
|
|
|
float *refi, *refq, *ci, *cq, *cfi, *cfq;
|
|
|
|
refi=calloc(nc2,sizeof(float));
|
|
refq=calloc(nc2,sizeof(float));
|
|
ci=calloc(nc2,sizeof(float));
|
|
cq=calloc(nc2,sizeof(float));
|
|
cfi=calloc(nc2,sizeof(float));
|
|
cfq=calloc(nc2,sizeof(float));
|
|
|
|
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;
|
|
}
|
|
}
|
|
|
|
float w[nfilt], norm=0, partialsum[nfilt];
|
|
//lowpass filter and remove startup transient
|
|
for (i=0; i<nfilt; i++) partialsum[i]=0.0;
|
|
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];
|
|
}
|
|
|
|
// 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];
|
|
}
|
|
}
|
|
|
|
// 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;
|
|
FILE *fp;
|
|
|
|
fp = fopen(c2filename,"wb");
|
|
if( fp == NULL ) {
|
|
fprintf(stderr, "Could not open c2 file '%s'\n", c2filename);
|
|
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);
|
|
|
|
buffer=calloc(2*45000,sizeof(float));
|
|
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);
|
|
free(buffer);
|
|
if( nwrite == 2*45000 ) {
|
|
return nwrite;
|
|
} else {
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
unsigned int count_hard_errors( unsigned char *symbols, unsigned char *channel_symbols)
|
|
{
|
|
int i,is;
|
|
unsigned char cw[162];
|
|
unsigned int nerrors;
|
|
for (i=0; i<162; i++) {
|
|
cw[i] = channel_symbols[i] >=2 ? 1:0;
|
|
}
|
|
deinterleave(cw);
|
|
nerrors=0;
|
|
for (i=0; i<162; i++) {
|
|
is = symbols[i] > 127 ? 1:0;
|
|
nerrors = nerrors + (is == cw[i] ? 0:1);
|
|
}
|
|
return nerrors;
|
|
}
|
|
|
|
//***************************************************************************
|
|
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(" -B disable block demodulation - use single-symbol noncoherent demod\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(" -o n (0<=n<=5), decoding depth for OSD, default is disabled\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[])
|
|
{
|
|
char cr[] = "(C) 2018, Steven Franke - K9AN";
|
|
(void)cr;
|
|
extern char *optarg;
|
|
extern int optind;
|
|
int i,j,k;
|
|
unsigned char *symbols, *decdata, *channel_symbols, *apmask, *cw;
|
|
signed char message[]={-9,13,-35,123,57,-39,64,0,0,0,0};
|
|
char *callsign, *grid, *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 usehashtable=1,wspr_type=2, ipass, nblocksize;
|
|
int nhardmin,ihash;
|
|
int writec2=0,maxdrift;
|
|
int shift1, lagmin, lagmax, lagstep, ifmin, ifmax, not_decoded;
|
|
unsigned int nbits=81, stacksize=200000;
|
|
unsigned int npoints, cycles, maxnp, metric;
|
|
float df=375.0/256.0/2;
|
|
float fsymbs[162];
|
|
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 dmin;
|
|
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,tosd=0.0,ttotal=0.0;
|
|
|
|
struct cand { float freq; float snr; int shift; float drift; float sync; };
|
|
struct cand candidates[200];
|
|
|
|
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; int blocksize; unsigned int metric;
|
|
int nhardmin; int ipass; int decodetype;};
|
|
struct result decodes[50];
|
|
|
|
char *hashtab;
|
|
hashtab=calloc(32768*13,sizeof(char));
|
|
char *loctab;
|
|
loctab=calloc(32768*5,sizeof(char));
|
|
int nh;
|
|
symbols=calloc(nbits*2,sizeof(unsigned char));
|
|
apmask=calloc(162,sizeof(unsigned char));
|
|
cw=calloc(162,sizeof(unsigned char));
|
|
decdata=calloc(11,sizeof(unsigned char));
|
|
channel_symbols=calloc(nbits*2,sizeof(unsigned char));
|
|
callsign=calloc(13,sizeof(char));
|
|
grid=calloc(5,sizeof(char));
|
|
call_loc_pow=calloc(23,sizeof(char));
|
|
float allfreqs[100];
|
|
char allcalls[100][13];
|
|
for (i=0; i<100; i++) allfreqs[i]=0.0;
|
|
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 subtraction=1;
|
|
int npasses=3;
|
|
int ndepth=-1; //Depth for OSD
|
|
|
|
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=calloc(maxpts,sizeof(float));
|
|
qdat=calloc(maxpts,sizeof(float));
|
|
|
|
while ( (c = getopt(argc, argv, "a:BcC:de:f:HJmo:qstwvz:")) !=-1 ) {
|
|
switch (c) {
|
|
case 'a':
|
|
data_dir = optarg;
|
|
break;
|
|
case 'B':
|
|
npasses=2;
|
|
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 'o': //use ordered-statistics-decoder
|
|
ndepth=(int) strtol(optarg,NULL,10);
|
|
break;
|
|
case 'q': //no shift jittering
|
|
quickmode = 1;
|
|
break;
|
|
case 's': //single pass mode
|
|
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=calloc(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
|
|
int nr=fscanf(ftimer,"%f %f %f %f %f %f %f %f",
|
|
&treadwav,&tcandidates,&tsync0,&tsync1,&tsync2,&tfano,&tosd,&ttotal);
|
|
fclose(ftimer);
|
|
if(nr == 0) fprintf(stderr, "Empty timer file: '%s'\n", timer_fname);
|
|
}
|
|
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[13], hgrid[5];
|
|
if( (fhash=fopen(hash_fname,"r+")) ) {
|
|
while (fgets(line, sizeof(line), fhash) != NULL) {
|
|
hgrid[0]='\0';
|
|
sscanf(line,"%d %s %s",&nh,hcall,hgrid);
|
|
strcpy(hashtab+nh*13,hcall);
|
|
if(strlen(hgrid)>0) strcpy(loctab+nh*5,hgrid);
|
|
}
|
|
} else {
|
|
fhash=fopen(hash_fname,"w+");
|
|
}
|
|
fclose(fhash);
|
|
}
|
|
|
|
//*************** main loop starts here *****************
|
|
for (ipass=0; ipass<npasses; ipass++) {
|
|
if(ipass==1 && ndecodes_pass == 0) ipass=2;
|
|
if(ipass < 2) {
|
|
nblocksize=1;
|
|
maxdrift=4;
|
|
minsync2=0.12;
|
|
}
|
|
if(ipass == 2 ) {
|
|
nblocksize=4; // try 3 blocksizes plus bitbybit normalization
|
|
maxdrift=0; // no drift for smaller frequency estimator variance
|
|
minsync2=0.10;
|
|
}
|
|
ndecodes_pass=0; // still needed?
|
|
|
|
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
|
|
for (i=0; i<512; i++) psavg[i]=0.0;
|
|
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,-8.0/10.0); //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++) {
|
|
candidates[i].freq=0.0;
|
|
candidates[i].snr=0.0;
|
|
candidates[i].drift=0.0;
|
|
candidates[i].shift=0;
|
|
candidates[i].sync=0.0;
|
|
}
|
|
|
|
int npk=0;
|
|
unsigned char candidate;
|
|
for(j=1; j<410; j++) {
|
|
candidate = (smspec[j]>smspec[j-1]) &&
|
|
(smspec[j]>smspec[j+1]) &&
|
|
(npk<200);
|
|
if ( candidate ) {
|
|
candidates[npk].freq = (j-205)*df;
|
|
candidates[npk].snr = 10*log10(smspec[j])-snr_scaling_factor;
|
|
npk++;
|
|
}
|
|
}
|
|
if( more_candidates ) {
|
|
for(j=0; j<411; j=j+3) {
|
|
candidate = (smspec[j]>min_snr) && (npk<200);
|
|
if ( candidate ) {
|
|
candidates[npk].freq = (j-205)*df;
|
|
candidates[npk].snr = 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( candidates[j].freq >= fmin && candidates[j].freq <= fmax ) {
|
|
candidates[i]=candidates[j];
|
|
i++;
|
|
}
|
|
}
|
|
npk=i;
|
|
|
|
// bubble sort on snr
|
|
int pass;
|
|
struct cand tmp;
|
|
for (pass = 1; pass <= npk - 1; pass++) {
|
|
for (k = 0; k < npk - pass ; k++) {
|
|
if (candidates[k].snr < candidates[k+1].snr) {
|
|
tmp = candidates[k];
|
|
candidates[k]=candidates[k+1];
|
|
candidates[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=candidates[j].freq/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;
|
|
candidates[j].shift=128*(k0+1);
|
|
candidates[j].drift=idrift;
|
|
candidates[j].freq=(ifr-256)*df;
|
|
candidates[j].sync=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++) {
|
|
|
|
f1=candidates[j].freq;
|
|
drift1=candidates[j].drift;
|
|
shift1=candidates[j].shift;
|
|
sync1=candidates[j].sync;
|
|
|
|
// 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);
|
|
|
|
if(ipass < 2) {
|
|
// 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;
|
|
|
|
candidates[j].freq=f1;
|
|
candidates[j].shift=shift1;
|
|
candidates[j].drift=drift1;
|
|
candidates[j].sync=sync1;
|
|
}
|
|
}
|
|
|
|
int nwat=0;
|
|
int idupe;
|
|
for ( j=0; j<npk; j++) {
|
|
idupe=0;
|
|
for (k=0;k<nwat;k++) {
|
|
if( fabsf(candidates[j].freq - candidates[k].freq) < 0.05 &&
|
|
abs(candidates[j].shift - candidates[k].shift) < 16 ) {
|
|
idupe=1;
|
|
break;
|
|
}
|
|
}
|
|
if( idupe == 1 ) {
|
|
if(candidates[j].sync > candidates[k].sync) candidates[k]=candidates[j];
|
|
} else if ( candidates[j].sync > minsync2 ) {
|
|
candidates[nwat]=candidates[j];
|
|
nwat++;
|
|
}
|
|
}
|
|
|
|
int idt, ii, jittered_shift;
|
|
float y,sq,rms;
|
|
int ib, blocksize, bitmetric;
|
|
int n1,n2,n3,nadd,nu,ntype;
|
|
int osd_decode;
|
|
for (j=0; j<nwat; j++) {
|
|
memset(symbols,0,sizeof(char)*nbits*2);
|
|
memset(callsign,0,sizeof(char)*13);
|
|
memset(grid,0,sizeof(char)*5);
|
|
memset(call_loc_pow,0,sizeof(char)*23);
|
|
f1=candidates[j].freq;
|
|
shift1=candidates[j].shift;
|
|
drift1=candidates[j].drift;
|
|
not_decoded=1;
|
|
osd_decode=0;
|
|
|
|
ib=1;
|
|
while( ib <= nblocksize && not_decoded ) {
|
|
if (ib < 4) { blocksize=ib; bitmetric=0; }
|
|
if (ib == 4) { blocksize=1; bitmetric=1; }
|
|
|
|
idt=0; ii=0;
|
|
while ( not_decoded && idt<=(128/iifac)) {
|
|
ii=(idt+1)/2;
|
|
if( idt%2 == 1 ) ii=-ii;
|
|
ii=iifac*ii;
|
|
jittered_shift=shift1+ii;
|
|
nhardmin=0; dmin=0.0;
|
|
|
|
// Get soft-decision symbols
|
|
t0 = clock();
|
|
noncoherent_sequence_detection(idat, qdat, npoints, symbols, &f1,
|
|
&jittered_shift, &drift1, symfac, &blocksize, &bitmetric);
|
|
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(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;
|
|
|
|
if( (ndepth >= 0) && not_decoded ) {
|
|
for(i=0; i<162; i++) {
|
|
fsymbs[i]=symbols[i]-128.0;
|
|
}
|
|
t0 = clock();
|
|
osdwspr_(fsymbs,apmask,&ndepth,cw,&nhardmin,&dmin);
|
|
tosd += (float)(clock()-t0)/CLOCKS_PER_SEC;
|
|
|
|
for(i=0; i<162; i++) {
|
|
symbols[i]=255*cw[i];
|
|
}
|
|
fano(&metric,&cycles,&maxnp,decdata,symbols,nbits,
|
|
mettab,delta,maxcycles);
|
|
for(i=0; i<11; i++) {
|
|
if( decdata[i]>127 ) {
|
|
message[i]=decdata[i]-256;
|
|
} else {
|
|
message[i]=decdata[i];
|
|
}
|
|
}
|
|
unpack50(message,&n1,&n2);
|
|
if( !unpackcall(n1,callsign) ) break;
|
|
callsign[12]=0;
|
|
if( !unpackgrid(n2, grid) ) break;
|
|
grid[4]=0;
|
|
ntype = (n2&127) - 64;
|
|
int itype;
|
|
if( (ntype >= 0) && (ntype <= 62) ) {
|
|
nu = ntype%10;
|
|
itype=1;
|
|
if( !(nu == 0 || nu == 3 || nu == 7) ) {
|
|
nadd=nu;
|
|
if( nu > 3 ) nadd=nu-3;
|
|
if( nu > 7 ) nadd=nu-7;
|
|
n3=n2/128+32768*(nadd-1);
|
|
if( !unpackpfx(n3,callsign) ) {
|
|
break;
|
|
}
|
|
itype=2;
|
|
}
|
|
ihash=nhash(callsign,strlen(callsign),(uint32_t)146);
|
|
if(strncmp(hashtab+ihash*13,callsign,13)==0) {
|
|
if( (itype==1 && strncmp(loctab+ihash*5,grid,5)==0) ||
|
|
(itype==2) ) {
|
|
not_decoded=0;
|
|
osd_decode =1;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
}
|
|
idt++;
|
|
if( quickmode ) break;
|
|
}
|
|
ib++;
|
|
}
|
|
|
|
if( !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,loctab,call_loc_pow,callsign);
|
|
if( subtraction && !noprint ) {
|
|
if( get_wspr_channel_symbols(call_loc_pow, hashtab, loctab, channel_symbols) ) {
|
|
subtract_signal2(idat, qdat, npoints, f1, shift1, drift1, channel_symbols);
|
|
if(!osd_decode) nhardmin=count_hard_errors(symbols,channel_symbols);
|
|
} else {
|
|
break;
|
|
}
|
|
}
|
|
|
|
// Remove dupes (same callsign and freq within 4 Hz)
|
|
int dupe=0;
|
|
for (i=0; i<uniques; i++) {
|
|
if(!strcmp(callsign,allcalls[i]) &&
|
|
(fabs(f1-allfreqs[i]) <4.0)) 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=candidates[j].sync;
|
|
decodes[uniques-1].snr=candidates[j].snr;
|
|
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;
|
|
decodes[uniques-1].blocksize=blocksize+3*bitmetric;
|
|
decodes[uniques-1].metric=metric;
|
|
decodes[uniques-1].nhardmin=nhardmin;
|
|
decodes[uniques-1].ipass=ipass;
|
|
decodes[uniques-1].decodetype=osd_decode;
|
|
}
|
|
}
|
|
}
|
|
|
|
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 %3.0f %5.2f %11.7f %-22s %2d %5.2f %2d %2d %4d %2d %3d %5u %5d\n",
|
|
decodes[i].date, decodes[i].time, decodes[i].snr,
|
|
decodes[i].dt, decodes[i].freq, decodes[i].message,
|
|
(int)decodes[i].drift, decodes[i].sync,
|
|
decodes[i].ipass+1,decodes[i].blocksize,decodes[i].jitter,
|
|
decodes[i].decodetype,decodes[i].nhardmin,decodes[i].cycles/81,
|
|
decodes[i].metric);
|
|
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 %7.2f\n\n",
|
|
treadwav,tcandidates,tsync0,tsync1,tsync2,tfano,tosd,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,"OSD decoder %7.2f %7.2f\n",tosd,tosd/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 %s\n",i,hashtab+i*13,loctab+i*5);
|
|
}
|
|
}
|
|
fclose(fhash);
|
|
}
|
|
|
|
free(hashtab);
|
|
free(loctab);
|
|
free(symbols);
|
|
free(decdata);
|
|
free(channel_symbols);
|
|
free(callsign);
|
|
free(call_loc_pow);
|
|
free(idat);
|
|
free(qdat);
|
|
if( stackdecoder ) {
|
|
free(stack);
|
|
}
|
|
|
|
return 0;
|
|
}
|