mirror of
https://github.com/saitohirga/WSJT-X.git
synced 2024-11-09 02:26:06 -05:00
103 lines
2.4 KiB
Fortran
103 lines
2.4 KiB
Fortran
program rtty_spec
|
|
|
|
! Generate simulated data for standard RTTY and WSJT-X modes FT8, FT4
|
|
|
|
use wavhdr
|
|
use packjt
|
|
parameter (NMAX=15*12000)
|
|
type(hdr) h
|
|
complex cwave(NMAX)
|
|
real wave(NMAX)
|
|
real*4 dat(NMAX) !Generated waveform
|
|
integer*2 iwave(NMAX) !Generated waveform
|
|
integer itone(680) !Channel symbols (values 0-1, 0-3, 0-7)
|
|
integer*1 msgbits(77)
|
|
character*37 msg37,msgsent37
|
|
character*8 arg
|
|
|
|
nargs=iargc()
|
|
if(nargs.ne.1) then
|
|
print*,'Usage: rtty_spec <snr>'
|
|
go to 999
|
|
endif
|
|
call getarg(1,arg)
|
|
read(arg,*) snrdb !S/N in dB (2500 hz reference BW)
|
|
|
|
rmsdb=25.
|
|
rms=10.0**(0.05*rmsdb)
|
|
sig=10.0**(0.05*snrdb)
|
|
npts=NMAX
|
|
|
|
do i=1,NMAX !Generate gaussian noise
|
|
dat(i)=gran()
|
|
enddo
|
|
|
|
! Add the RTTY signal
|
|
fsample=12000.0 !Sample rate (Hz)
|
|
dt=1.0/fsample !Sample interval (s)
|
|
twopi=8.0*atan(1.0)
|
|
phi=0.
|
|
dphi=0.
|
|
j0=-1
|
|
do i=6001,NMAX-6000
|
|
j=nint(i*dt/0.022)
|
|
if(j.ne.j0) then
|
|
f0=1415.0
|
|
call random_number(rr)
|
|
if(rr.gt.0.5) f0=1585.0
|
|
dphi=twopi*f0*dt
|
|
j0=j
|
|
endif
|
|
phi=phi+dphi
|
|
if(phi.gt.twopi) phi=phi-twopi
|
|
dat(i)=dat(i) + sig*sin(phi)
|
|
enddo
|
|
|
|
! FT8 signal (FSK)
|
|
i3=0
|
|
n3=0
|
|
msg37='WB9XYZ KA2ABC FN42'
|
|
call genft8(msg37,i3,n3,msgsent37,msgbits,itone)
|
|
nsym=79
|
|
nsps=1920
|
|
bt=99.0
|
|
f0=3500.0
|
|
icmplx=0
|
|
nwave=nsym*nsps
|
|
call gen_ft8wave(itone,nsym,nsps,bt,fsample,f0,cwave,wave,icmplx,nwave)
|
|
dat(6001:6000+nwave)=dat(6001:6000+nwave) + sig*wave(1:nwave)
|
|
|
|
! FT8 signal (GFSK)
|
|
i3=0
|
|
n3=0
|
|
msg37='WB9XYZ KA2ABC FN42'
|
|
call genft8(msg37,i3,n3,msgsent37,msgbits,itone)
|
|
nsym=79
|
|
nsps=1920
|
|
bt=2.0
|
|
f0=4000.0
|
|
icmplx=0
|
|
nwave=nsym*nsps
|
|
call gen_ft8wave(itone,nsym,nsps,bt,fsample,f0,cwave,wave,icmplx,nwave)
|
|
dat(6001:6000+nwave)=dat(6001:6000+nwave) + sig*wave(1:nwave)
|
|
|
|
! Add the FT4 signal
|
|
ichk=0
|
|
call genft4(msg37,ichk,msgsent37,msgbits,itone)
|
|
nsym=103
|
|
nsps=576
|
|
f0=4500.0
|
|
icmplx=0
|
|
nwave=(nsym+2)*nsps
|
|
call gen_ft4wave(itone,nsym,nsps,fsample,f0,cwave,wave,icmplx,nwave)
|
|
dat(6001:6000+nwave)=dat(6001:6000+nwave) + sig*wave(1:nwave)
|
|
|
|
h=default_header(12000,NMAX)
|
|
datmax=maxval(abs(dat))
|
|
iwave=nint(32767.0*dat/datmax)
|
|
open(10,file='000000_000001.wav',access='stream',status='unknown')
|
|
write(10) h,iwave
|
|
close(10)
|
|
|
|
999 end program rtty_spec
|