program ft280sim ! Generate simulated signals for experimental slow FT4 mode use wavhdr use packjt77 include 'ft4s280_params.f90' !Set various constants type(hdr) h !Header for .wav file character arg*12,fname*17 character msg37*37,msgsent37*37 character c77*77 complex c0(0:NMAX-1) complex c(0:NMAX-1) real wave(NMAX) integer itone(NN) integer*1 msgbits(101) integer*2 iwave(NMAX) !Generated full-length waveform ! Get command-line argument(s) nargs=iargc() if(nargs.ne.8) then print*,'Usage: ft280sim "message" f0 DT h fdop del nfiles snr' print*,'Examples: ft280sim "K1JT K9AN EN50" 1500 0.0 1.0 0.1 1.0 10 -15' go to 999 endif call getarg(1,msg37) !Message to be transmitted call getarg(2,arg) read(arg,*) f0 !Frequency (only used for single-signal) call getarg(3,arg) read(arg,*) xdt !Time offset from nominal (s) call getarg(4,arg) read(arg,*) hmod !Modulation index, h call getarg(5,arg) read(arg,*) fspread !Watterson frequency spread (Hz) call getarg(6,arg) read(arg,*) delay !Watterson delay (ms) call getarg(7,arg) read(arg,*) nfiles !Number of files call getarg(8,arg) read(arg,*) snrdb !SNR_2500 nfiles=abs(nfiles) twopi=8.0*atan(1.0) fs=12000.0 !Sample rate (Hz) dt=1.0/fs !Sample interval (s) tt=NSPS*dt !Duration of symbols (s) baud=1.0/tt !Keying rate (baud) txt=NZ2*dt !Transmission length (s) 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 call genft280(msg37,0,msgsent37,msgbits,itone) write(*,*) write(*,'(a9,a37,3x,a7,i1,a1,i1)') 'Message: ',msgsent37,'i3.n3: ',i3,'.',n3 write(*,1000) f0,xdt,hmod,txt,snrdb 1000 format('f0:',f9.3,' DT:',f6.2,' hmod:',f6.3,' 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(*,'(50i1,1x,24i1)') msgbits endif write(*,*) write(*,'(a17)') 'Channel symbols: ' write(*,'(10i1)') itone write(*,*) call sgran() fsample=12000.0 icmplx=1 call gen_wspr4wave(itone,NN,NSPS,fsample,hmod,f0,c0,wave,icmplx,NMAX) k=nint((xdt+1.0)/dt)-NSPS 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.ne.0.0 .or. delay.ne.0.0) call watterson(c,NMAX,NZ,fs,delay,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) h=default_header(12000,NMAX) write(fname,1102) ifile 1102 format('000000_',i6.6,'.wav') open(10,file=fname,status='unknown',access='stream') write(10) h,iwave !Save to *.wav file close(10) write(*,1110) ifile,xdt,f0,snrdb,fname 1110 format(i4,f7.2,f8.2,f7.1,2x,a17) enddo 999 end program ft280sim