mirror of
https://github.com/saitohirga/WSJT-X.git
synced 2024-11-08 18:16:02 -05:00
7047150453
git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@7712 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
105 lines
3.3 KiB
Fortran
105 lines
3.3 KiB
Fortran
program ft8sim
|
|
|
|
! Generate simulated data for a 15-second HF/6m mode using 8-FSK.
|
|
! Output is saved to a *.wav file.
|
|
|
|
use wavhdr
|
|
include 'ft8_params.f90' !Set various constants
|
|
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)
|
|
integer itone(NN)
|
|
integer*2 iwave(NMAX) !Generated full-length waveform
|
|
|
|
! Get command-line argument(s)
|
|
nargs=iargc()
|
|
if(nargs.ne.7) then
|
|
print*,'Usage: ft8sim "message" f0 DT fdop del nfiles snr'
|
|
print*,'Example: ft8sim "K1ABC W9XYZ EN37" 1500 0.0 0.1 1.0 10 -18'
|
|
go to 999
|
|
endif
|
|
call getarg(1,msg) !Message to be transmitted
|
|
call getarg(2,arg)
|
|
read(arg,*) f0 !Freq of tone 0 (Hz)
|
|
call getarg(3,arg)
|
|
read(arg,*) xdt !Time offset from nominal (s)
|
|
call getarg(4,arg)
|
|
read(arg,*) fspread !Watterson frequency spread (Hz)
|
|
call getarg(5,arg)
|
|
read(arg,*) delay !Watterson delay (ms)
|
|
call getarg(6,arg)
|
|
read(arg,*) nfiles !Number of files
|
|
call getarg(7,arg)
|
|
read(arg,*) snrdb !SNR_2500
|
|
|
|
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)
|
|
bw=8*baud !Occupied bandwidth (Hz)
|
|
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*NSPS/12000.0
|
|
|
|
call genft8(msg,msgsent,itone) !Source-encode, then get itone()
|
|
write(*,1000) f0,xdt,txt,snrdb,bw,msgsent
|
|
1000 format('f0:',f9.3,' DT:',f6.2,' TxT:',f6.1,' SNR:',f6.1, &
|
|
' BW:',f4.1,2x,a22)
|
|
|
|
phi=0.0
|
|
c0=0.
|
|
k=-1 + nint(xdt/dt)
|
|
do j=1,NN !Generate 8-FSK waveform from itone
|
|
dphi=twopi*(f0+itone(j)*baud)*dt
|
|
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
|
|
|
|
call sgran()
|
|
do ifile=1,nfiles
|
|
c=c0
|
|
if( fspread .ne. 0.0 .or. delay .ne. 0.0 ) then
|
|
call watterson(c,NZ,fs,delay,fspread)
|
|
endif
|
|
c=c*sig
|
|
if(snrdb.lt.90) then
|
|
do i=0,NZ-1 !Add gaussian noise at specified SNR
|
|
xnoise=gran()
|
|
ynoise=gran()
|
|
c(i)=c(i) + cmplx(xnoise,ynoise)
|
|
enddo
|
|
endif
|
|
|
|
fac=32767.0
|
|
rms=100.0
|
|
if(snrdb.ge.90.0) iwave(1:NZ)=nint(fac*real(c))
|
|
if(snrdb.lt.90.0) iwave(1:NZ)=nint(rms*real(c))
|
|
iwave(NZ+1:)=0
|
|
|
|
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)
|
|
write(*,1110) ifile,xdt,f0,snrdb,fname
|
|
1110 format(i4,f7.2,f8.2,f7.1,2x,a16)
|
|
do i=0,NZ-1
|
|
write(13,3001) i,i/12000.0,c(i),iwave(i+1)
|
|
3001 format(i8,f12.6,2f12.3,i8)
|
|
enddo
|
|
enddo
|
|
|
|
999 end program ft8sim
|