subroutine jtmsk(id2,narg,line) ! Decoder for JTMSK parameter (NMAX=30*12000) parameter (NFFTMAX=512*1024) parameter (NSPM=1404) !Samples per JTMSK message integer*2 id2(0:NMAX) !Raw i*2 data, up to T/R = 30 s real d(0:NMAX) !Raw r*4 data real ty(703) real yellow(703) ! real spk2(20) ! real fpk2(20) ! integer jpk2(20) complex c(NFFTMAX) !Complex (analytic) data complex cdat(24000) !Short segments, up to 2 s complex cdat2(24000) integer narg(0:11) !Arguments passed from calling pgm character*22 msg,msg0 !Decoded message character*80 line(100) !Decodes passed back to caller common/tracer/ limtrace,lu limtrace=-1 lu=12 ! Parameters from GUI are in narg(): nutc=narg(0) !UTC npts=min(narg(1),NMAX) !Number of samples in id2 (12000 Hz) newdat=narg(3) !1==> new data, compute symbol spectra minsync=narg(4) !Lower sync limit npick=narg(5) t0=0.001*narg(6) t1=0.001*narg(7) maxlines=narg(8) !Max # of decodes to return to caller nmode=narg(9) nrxfreq=narg(10) !Target Rx audio frequency (Hz) ntol=narg(11) !Search range, +/- ntol (Hz) nsnr0=-99 nline=0 line(1:100)(1:1)=char(0) msg0=' ' msg=msg0 d(0:npts-1)=id2(0:npts-1) rms=sqrt(dot_product(d(0:npts-1),d(0:npts-1))/npts) d(0:npts-1)=d(0:npts-1)/rms call timer('mskdt ',0) call mskdt(d,npts,ty,yellow,nyel) nyel=min(nyel,5) call timer('mskdt ',1) n=log(float(npts))/log(2.0) + 1.0 nfft=min(2**n,1024*1024) call timer('analytic',0) call analytic(d,npts,nfft,c) !Convert to analytic signal call timer('analytic',1) nbefore=NSPM nafter=4*NSPM ! Process ping list (sorted by S/N) from top down. do n=1,nyel ia=ty(n)*12000.0 - nbefore if(ia.lt.1) ia=1 ib=ia + nafter if(ib.gt.NFFTMAX) ib=NFFTMAX iz=ib-ia+1 cdat2(1:iz)=c(ia:ib) !Select nlen complex samples ja=ia/NSPM + 1 jb=ib/NSPM t0=ia/12000.0 ! call msksync(cdat,iz,jpk2,fpk2,spk2) ! call softmsk(cdat,iz,jpk2,fpk2,spk2) do itry=1,21 idf1=(itry/2) * 50 if(mod(itry,2).eq.1) idf1=-idf1 if(abs(idf1).gt.ntol) exit fpk=idf1 + nrxfreq call timer('tweak1 ',0) call tweak1(cdat2,iz,1500.0-fpk,cdat) call timer('tweak1 ',1) call timer('syncmsk ',0) call syncmsk(cdat,iz,jpk,ipk,idf,rmax,snr,metric,msg) call timer('syncmsk ',1) freq=fpk+idf ! write(72,4001) jpk,idf,nint(freq),rmax,snr,msg !4001 format(3i6,2f9.2,2x,a22) if(metric.eq.-9999) cycle !No output if no significant sync t0=(ia+jpk)/12000.0 nsnr=nint(yellow(n)-2.0) if(msg.ne.' ') then if(msg.ne.msg0) then nline=nline+1 nsnr0=-99 endif if(nsnr.gt.nsnr0) then call rectify_msk(cdat2(jpk:jpk+NSPM-1),msg,freq2) write(line(nline),1020) nutc,nsnr,t0,nint(freq2),msg 1020 format(i6.6,i4,f5.1,i5,' & ',a22) nsnr0=nsnr go to 900 endif msg0=msg if(nline.ge.maxlines) go to 900 endif enddo enddo 900 if(line(1)(1:6).eq.' ') line(1)(1:1)=char(0) return end subroutine jtmsk