108 lines
3.4 KiB
Fortran
108 lines
3.4 KiB
Fortran
program wspr_fsk8_sim
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! Generate simulated data for a 4-minute "WSPR-LF" mode using 8-FSK.
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! Output is saved to a *.wav file.
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use wavhdr
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include 'wspr_fsk8_params.f90' !Set various constants
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type(hdr) h !Header for .wav file
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character arg*12,fname*16
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character msg*22,msgsent*22
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complex c0(0:NZ-1)
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complex c(0:NZ-1)
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real*8 fMHz
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integer itone(NN)
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integer*2 iwave(NMAX) !Generated full-length waveform
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! Get command-line argument(s)
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nargs=iargc()
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if(nargs.ne.8) then
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print*,'Usage: wspr5sim "message" f0 DT fsp del nwav nfiles snr'
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print*,'Example: wspr5sim "K1ABC FN42 30" 50 0.0 0.1 1.0 1 10 -33'
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go to 999
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endif
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call getarg(1,msg) !Message to be transmitted
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call getarg(2,arg)
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read(arg,*) f0 !Freq relative to WSPR-band center (Hz)
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call getarg(3,arg)
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read(arg,*) xdt !Time offset from nominal (s)
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call getarg(4,arg)
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read(arg,*) fspread !Watterson frequency spread (Hz)
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call getarg(5,arg)
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read(arg,*) delay !Watterson delay (ms)
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call getarg(6,arg)
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read(arg,*) nwav !1 for *.wav file, 0 for *.c4 file
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call getarg(7,arg)
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read(arg,*) nfiles !Number of files
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call getarg(8,arg)
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read(arg,*) snrdb !SNR_2500
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twopi=8.0*atan(1.0)
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fs=12000.0/NDOWN !Sample rate after downsampling
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dt=1.0/fs !Sample interval (s)
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tt=NSPS*dt !Duration of symbols (s)
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baud=1.0/tt !Keying rate
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bw=8*baud
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txt=NZ*dt !Transmission length (s)
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bandwidth_ratio=2500.0/(fs/2.0)
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sig=sqrt(bandwidth_ratio) * 10.0**(0.05*snrdb)
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if(snrdb.gt.90.0) sig=1.0
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txt=NN*NSPS0/12000.0
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call genwspr_fsk8(msg,msgsent,itone) !Encode the message, get itone
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write(*,1000) f0,xdt,txt,snrdb,bw,msgsent
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1000 format('f0:',f9.3,' DT:',f6.2,' TxT:',f6.1,' SNR:',f6.1, &
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' BW:',f4.1,2x,a22)
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phi=0.0
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c0=0.
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k=-1 + nint(xdt/dt)
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do j=1,NN !Generate OQPSK waveform from itone
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dphi=twopi*(f0+itone(j)*baud)*dt
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if(k.eq.0) phi=-dphi
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do i=1,NSPS
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k=k+1
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phi=phi+dphi
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if(phi.gt.twopi) phi=phi-twopi
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xphi=phi
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if(k.ge.0 .and. k.lt.NZ) c0(k)=cmplx(cos(xphi),sin(xphi))
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enddo
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enddo
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call sgran()
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do ifile=1,nfiles
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if(nwav.eq.0) then
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c=c0
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if( fspread .ne. 0.0 .or. delay .ne. 0.0 ) then
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call watterson(c,NZ,fs,delay,fspread)
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endif
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c=c*sig
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if( snrdb.lt.90) then
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do i=0,NZ-1
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xnoise=gran()
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ynoise=gran()
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c(i)=c(i)+cmplx(xnoise,ynoise)
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enddo
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endif
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write(fname,1100) ifile
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1100 format('000000_',i4.4,'.c4')
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open(10,file=fname,status='unknown',access='stream')
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fMHz=1.866d0
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nmin=4
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write(10) fname,nmin,fMHz,c
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else
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call wspr_fsk8_wav(baud,xdt,f0,itone,snrdb,iwave)
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h=default_header(12000,NMAX)
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write(fname,1102) ifile
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1102 format('000000_',i4.4,'.wav')
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open(10,file=fname,status='unknown',access='stream')
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write(10) h,iwave !Save to *.wav file
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close(10)
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endif
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write(*,1110) ifile,xdt,f0,snrdb,fname
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1110 format(i4,f7.2,f8.2,f7.1,2x,a16)
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enddo
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999 end program wspr_fsk8_sim
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