program ft4sim_mult ! Generate simulated signals for experimental "FT4" mode use wavhdr use packjt77 include 'ft4_params.f90' !FT4 protocol constants parameter (NWAVE=NN*NSPS) parameter (NZZ=65760) !Length of .wav file (4.48+1.0)*12000 type(hdr) h !Header for .wav file character arg*12,fname*17,cjunk*4 character msg37*37,msgsent37*37,c77*77 complex cwave0((NN+2)*NSPS) real wave0((NN+2)*NSPS) real wave(NZZ) real tmp(NZZ) integer itone(NN) integer*1 msgbits(77) integer*2 iwave(NZZ) !Generated full-length waveform integer icos4(4) data icos4/0,1,3,2/ ! Get command-line argument(s) nargs=iargc() if(nargs.ne.2) then print*,'Usage: ft4sim_mult nsigs nfiles' print*,'Example: ft4sim_mult 20 8 ' go to 999 endif call getarg(1,arg) read(arg,*) nsigs !Number of signals call getarg(2,arg) read(arg,*) nfiles !Number of files twopi=8.0*atan(1.0) fs=12000.0 !Sample rate (Hz) dt=1.0/fs !Sample interval (s) hmod=1.0 !Modulation index (0.5 is MSK, 1.0 is FSK) tt=NSPS*dt !Duration of unsmoothed symbols (s) baud=1.0/tt !Keying rate (baud) txt=NZ*dt !Transmission length (s) without ramp up/down bandwidth_ratio=2500.0/(fs/2.0) txt=NN*NSPS/12000.0 open(10,file='messages.txt',status='old',err=998) do ifile=1,nfiles 1 read(10,1001,end=999) cjunk,n 1001 format(a4,i2) if(cjunk.ne.'File' .or. n.ne.ifile) go to 1 wave=0. write(fname,1002) ifile 1002 format('000000_',i6.6,'.wav') do isig=1,nsigs read(10,1003,end=100) cjunk,isnr,xdt0,ifreq,msg37 1003 format(a4,30x,i3,f5.1,i5,1x,a37) if(cjunk.eq.'File') go to 100 if(isnr.lt.-16) isnr=-16 f0=ifreq*93.75/50.0 call random_number(r) xdt=r-0.5 ! Source-encode, then get itone() i3=-1 n3=-1 call pack77(msg37,i3,n3,c77) call genft4(msg37,0,msgsent37,msgbits,itone) nwave0=(NN+2)*NSPS icmplx=0 call gen_ft4wave(itone,NN,NSPS,12000.0,f0,cwave0,wave0,icmplx,nwave0) k0=nint((xdt+0.5)/dt) if(k0.lt.1) k0=1 tmp(:k0-1)=0.0 tmp(k0:k0+nwave0-1)=wave0 tmp(k0+nwave0:)=0.0 ! Insert this signal into wave() array sig=sqrt(2*bandwidth_ratio) * 10.0**(0.05*isnr) wave=wave + sig*tmp write(*,1100) fname(1:13),isig,isnr,xdt,nint(f0),msg37 1100 format(a13,i4,i5,f5.1,i6,2x,a37) enddo ! isig 100 backspace 10 do i=1,NZZ !Add gaussian noise at specified SNR xnoise=gran() wave(i)=wave(i) + xnoise enddo gain=30.0 wave=gain*wave if(any(abs(wave).gt.32767.0)) print*,"Warning - data will be clipped." iwave=nint(wave) h=default_header(12000,NZZ) open(12,file=fname,status='unknown',access='stream') write(12) h,iwave !Save to *.wav file close(12) print*,' ' enddo ! ifile go to 999 998 print*,'Cannot open file "messages.txt"' 999 end program ft4sim_mult