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wsprd.c
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wsprd.c
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/*
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 "pffft.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 *);
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;
float *fftin, *fftout;
PFFFT_Setup *fftsetup1, *fftsetup2;
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=pffft_aligned_malloc(sizeof(float)*2*(nfft1/2+1));
fftout=realin;
fftsetup1=pffft_new_setup(nfft1, PFFFT_REAL);
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);
pffft_transform_ordered(fftsetup1, realin, realin, NULL, PFFFT_FORWARD);
fftin=pffft_aligned_malloc(sizeof(float)*2*nfft2);
for (i=0; i<(size_t)nfft2; i++) {
j=i0+i;
if( i>(size_t)nh2 ) j=j-nfft2;
fftin[i*2]=fftout[j*2];
fftin[i*2+1]=fftout[j*2+1];
}
pffft_aligned_free(fftout);
fftout=pffft_aligned_malloc(sizeof(float)*2*nfft2);
fftsetup2=pffft_new_setup(nfft2, PFFFT_COMPLEX);
pffft_transform_ordered(fftsetup2, fftin, fftout, NULL, PFFFT_BACKWARD);
for (i=0; i<(size_t)nfft2; i++) {
idat[i]=fftout[i*2]/1000.0;
qdat[i]=fftout[i*2+1]/1000.0;
}
pffft_aligned_free(fftin);
pffft_aligned_free(fftout);
pffft_destroy_setup(fftsetup1);
pffft_destroy_setup(fftsetup2);
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);
fclose(fp);
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=".";
char 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;
struct snode *stack=NULL;
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();
float *fftin, *fftout;
PFFFT_Setup *fftsetup;
int fftmap[512];
#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( access(data_dir, R_OK | W_OK)) {
fprintf(stderr, "Error: inaccessible data directory: '%s'\n", data_dir);
usage();
return EXIT_FAILURE;
}
if( optind+1 > argc) {
usage();
return 1;
} else {
ptr_to_infile=argv[optind];
}
if( stackdecoder ) {
stack=calloc(stacksize,sizeof(struct snode));
}
// 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 *fall_wspr, *fwsprd, *fhash, *ftimer;
strcpy(all_fname,".");
strcpy(spots_fname,".");
strcpy(timer_fname,".");
strcpy(hash_fname,".");
if(data_dir != NULL) {
strncpy(all_fname,data_dir, sizeof all_fname);
strncpy(spots_fname,data_dir, sizeof spots_fname);
strncpy(timer_fname,data_dir, sizeof timer_fname);
strncpy(hash_fname,data_dir, sizeof hash_fname);
}
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);
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=pffft_aligned_malloc(sizeof(float)*2*512);
fftout=pffft_aligned_malloc(sizeof(float)*2*512);
fftsetup=pffft_new_setup(512, PFFFT_COMPLEX);
j = 0;
for(i = 0; i < 1024; ++i) fftin[i] = i;
pffft_zreorder(fftsetup, fftin, fftout, PFFFT_FORWARD);
for(i = 512; i < 1024; i += 2) fftmap[j++] = fftout[i];
for(i = 0; i < 512; i += 2) fftmap[j++] = fftout[i];
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 && npasses>2) ipass=2;
if(ipass < 2) {
nblocksize=1;