WSJT-X/lib/fsk4hf/wspr5sim.f90
Joe Taylor 2464009f46 Code cleanup and commenting.
git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@7661 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
2017-05-01 12:32:59 +00:00

103 lines
3.5 KiB
Fortran

program wspr5sim
! Generate simulated data for a 5-minute "WSPR-LF" mode. Output is saved
! to a *.c5 or *.wav file.
use wavhdr
include 'wsprlf_params.f90' !Set various constants
parameter (NMAX=300*12000)
type(hdr) h !Header for .wav file
character arg*12,fname*16
character msg*22,msgsent*22
complex c0(0:NZ-1)
complex c(0:NZ-1)
real*8 fMHz
integer itone(NN)
integer*2 iwave(NMAX) !Generated full-length waveform
! Get command-line argument(s)
nargs=iargc()
if(nargs.ne.6) then
print*,'Usage: wspr5sim "message" f0 DT nwav nfiles snr'
print*,'Example: wspr5sim "K1ABC FN42 30" 50 0.0 0 10 -33'
go to 999
endif
call getarg(1,msg) !Message to be transmitted
call getarg(2,arg)
read(arg,*) f0 !Freq relative to WSPR-band center (Hz)
call getarg(3,arg)
read(arg,*) xdt !Time offset from nominal (s)
call getarg(4,arg)
read(arg,*) nwav !1 for *.wav file, 0 for *.c5 file
call getarg(5,arg)
read(arg,*) nfiles !Number of files
call getarg(6,arg)
read(arg,*) snrdb !SNR_2500
twopi=8.0*atan(1.0)
fs=12000.0/NDOWN !Sample rate
dt=1.0/fs !Sample interval (s)
tt=NSPS*dt !Duration of "itone" symbols (s)
ts=2*NSPS*dt !Duration of OQPSK symbols (s)
baud=1.0/tt !Keying rate for "itone" symbols (baud)
txt=NZ*dt !Transmission length (s)
bandwidth_ratio=2500.0/(fs/2.0)
sig=sqrt(bandwidth_ratio) * 10.0**(0.05*snrdb)
if(snrdb.gt.90.0) sig=1.0
txt=NN*NSPS0/12000.0
call genwspr5(msg,ichk,msgsent,itone,itype) !Encode the message, get itone
write(*,1000) f0,xdt,txt,snrdb,nfiles,msgsent
1000 format('f0:',f9.3,' DT:',f6.2,' txt:',f6.1,' SNR:',f6.1, &
' nfiles:',i3,2x,a22)
dphi0=twopi*(f0-0.25*baud)*dt
dphi1=twopi*(f0+0.25*baud)*dt
phi=0.0
c0=0.
k=-1 + nint(xdt/dt)
do j=1,NN !Generate OQPSK waveform from itone
dphi=dphi0
if(itone(j).eq.1) dphi=dphi1
if(k.eq.0) phi=-dphi
do i=1,NSPS
k=k+1
phi=phi+dphi
if(phi.gt.twopi) phi=phi-twopi
xphi=phi
if(k.ge.0 .and. k.lt.NZ) c0(k)=cmplx(cos(xphi),sin(xphi))
enddo
enddo
c0=sig*c0 !Scale to requested sig level
do ifile=1,nfiles
if(nwav.eq.0) then
if(snrdb.lt.90) then
do i=0,NZ-1 !Add gaussian noise at specified SNR
xnoise=gran()
ynoise=gran()
c(i)=c0(i) + cmplx(xnoise,ynoise)
enddo
endif
write(fname,1100) ifile
1100 format('000000_',i4.4,'.c5')
open(10,file=fname,status='unknown',access='stream')
fMHz=10.1387d0
nmin=5
write(10) fname,nmin,fMHz,c !Save to *.c5 file
close(10)
else
call wspr5_wav(baud,xdt,f0,itone,snrdb,iwave)
h=default_header(12000,NMAX)
write(fname,1102) ifile
1102 format('000000_',i4.4,'.wav')
open(10,file=fname,status='unknown',access='stream')
write(10) h,iwave !Save to *.wav file
close(10)
endif
write(*,1110) ifile,xdt,f0,snrdb,fname
1110 format(i4,f7.2,f8.2,f7.1,2x,a16)
enddo
999 end program wspr5sim