program fst4sim ! Generate simulated signals for experimental slow FT4 mode use wavhdr use packjt77 include 'fst4_params.f90' !Set various constants type(hdr) h !Header for .wav file logical*1 wspr_hint character arg*12,fname*17 character msg37*37,msgsent37*37,c77*77 complex, allocatable :: c0(:) complex, allocatable :: c(:) real, allocatable :: wave(:) integer hmod integer itone(NN) integer*1 msgbits(101) integer*2, allocatable :: iwave(:) !Generated full-length waveform ! Get command-line argument(s) nargs=iargc() if(nargs.ne.10) then print*,'Need 10 arguments, got ',nargs print*,'Usage: fst4sim "message" TRsec f0 DT h fdop del nfiles snr W' print*,'Examples: fst4sim "K1JT K9AN EN50" 60 1500 0.0 1 0.1 1.0 10 -15 F' print*,'W (T or F) argument is hint to encoder to use WSPR message when there is abiguity' go to 999 endif call getarg(1,msg37) !Message to be transmitted call getarg(2,arg) read(arg,*) nsec !TR sequence length, seconds call getarg(3,arg) read(arg,*) f00 !Frequency (only used for single-signal) call getarg(4,arg) read(arg,*) xdt !Time offset from nominal (s) call getarg(5,arg) read(arg,*) hmod !Modulation index, h call getarg(6,arg) read(arg,*) fspread !Watterson frequency spread (Hz) call getarg(7,arg) read(arg,*) delay !Watterson delay (ms) call getarg(8,arg) read(arg,*) nfiles !Number of files call getarg(9,arg) read(arg,*) snrdb !SNR_2500 call getarg(10,arg) read(arg,*) wspr_hint !0:break ties as 77-bit 1:break ties as 50-bit nfiles=abs(nfiles) twopi=8.0*atan(1.0) fs=12000.0 !Sample rate (Hz) dt=1.0/fs !Sample interval (s) nsps=0 if(nsec.eq.15) nsps=720 if(nsec.eq.30) nsps=1680 if(nsec.eq.60) nsps=3888 if(nsec.eq.120) nsps=8200 if(nsec.eq.300) nsps=21504 if(nsec.eq.900) nsps=66560 if(nsec.eq.1800) nsps=134400 if(nsps.eq.0) then print*,'Invalid TR sequence length.' go to 999 endif baud=12000.0/nsps !Keying rate (baud) nmax=nsec*12000 nz=nsps*NN txt=nz*dt !Transmission length (s) tt=nsps*dt !Duration of symbols (s) nwave=max(nmax,(NN+2)*nsps) allocate( c0(0:nwave-1) ) allocate( c(0:nwave-1) ) allocate( wave(nwave) ) allocate( iwave(nmax) ) bandwidth_ratio=2500.0/(fs/2.0) sig=sqrt(2*bandwidth_ratio) * 10.0**(0.05*snrdb) if(snrdb.gt.90.0) sig=1.0 if(wspr_hint) then i3=0 n3=6 else i3=-1 n3=-1 endif call pack77(msg37,i3,n3,c77) if(i3.eq.0.and.n3.eq.6) iwspr=1 call genfst4(msg37,0,msgsent37,msgbits,itone,iwspr) write(*,*) write(*,'(a9,a37,a3,L2,a7,i2)') 'Message: ',msgsent37,'W:',wspr_hint,' iwspr:',iwspr write(*,1000) f00,xdt,hmod,txt,snrdb 1000 format('f0:',f9.3,' DT:',f6.2,' hmod:',i6,' TxT:',f6.1,' SNR:',f6.1) write(*,*) if(i3.eq.1) then write(*,*) ' mycall hiscall hisgrid' write(*,'(28i1,1x,i1,1x,28i1,1x,i1,1x,i1,1x,15i1,1x,3i1)') msgbits(1:77) else write(*,'(a14)') 'Message bits: ' write(*,'(77i1,1x,24i1)') msgbits endif write(*,*) write(*,'(a17)') 'Channel symbols: ' write(*,'(10i1)') itone write(*,*) ! call sgran() fsample=12000.0 icmplx=1 f0=f00+1.5*hmod*baud call gen_fst4wave(itone,NN,nsps,nwave,fsample,hmod,f0,icmplx,c0,wave) k=nint((xdt+1.0)/dt) if(nsec.eq.15) k=nint((xdt+0.5)/dt) c0=cshift(c0,-k) if(k.gt.0) c0(0:k-1)=0.0 if(k.lt.0) c0(nmax+k:nmax-1)=0.0 do ifile=1,nfiles c=c0 if(fspread.gt.0.0 .or. delay.ne.0.0) call watterson(c,nwave,NZ,fs,delay,fspread) if(fspread.lt.0.0) call lorentzian_fading(c,nwave,fs,-fspread) c=sig*c wave=real(c) if(snrdb.lt.90) then do i=1,nmax !Add gaussian noise at specified SNR xnoise=gran() wave(i)=wave(i) + xnoise enddo endif gain=100.0 if(snrdb.lt.90.0) then wave=gain*wave else datpk=maxval(abs(wave)) fac=32766.9/datpk wave=fac*wave endif if(any(abs(wave).gt.32767.0)) print*,"Warning - data will be clipped." iwave=nint(wave(:size(iwave))) h=default_header(12000,nmax) if(nmax/12000.le.30) then write(fname,1102) ifile 1102 format('000000_',i6.6,'.wav') else write(fname,1104) ifile 1104 format('000000_',i4.4,'.wav') endif open(10,file=trim(fname),status='unknown',access='stream') write(10) h,iwave !Save to *.wav file close(10) write(*,1110) ifile,xdt,f00,snrdb,fname 1110 format(i4,f7.2,f8.2,f7.1,2x,a17) enddo 999 end program fst4sim