WSJT-X/lib/msk144sim.f90

97 lines
2.4 KiB
Fortran
Raw Normal View History

program msk144sim
use wavhdr
parameter (NMAX=15*12000)
real pings(0:NMAX-1)
real waveform(0:NMAX-1)
character arg*8,msg*37,msgsent*37,fname*40
character*77 c77
real wave(0:NMAX-1) !Simulated received waveform
real*8 twopi,freq,phi,dphi0,dphi1,dphi
type(hdr) h !Header for .wav file
integer*2 iwave(0:NMAX-1)
integer itone(144) !Message bits
nargs=iargc()
if(nargs.ne.6) then
print*,'Usage: msk144sim message freq width nslow snr nfiles'
print*,'Example: msk144sim "K1ABC W9XYZ EN37" 1500 0.12 1 2 1'
print*,' msk144sim "K1ABC W9XYZ EN37" 1500 2.5 32 15 1'
go to 999
endif
call getarg(1,msg)
call getarg(2,arg)
read(arg,*) freq
call getarg(3,arg)
read(arg,*) width
call getarg(4,arg)
read(arg,*) nslow
call getarg(5,arg)
read(arg,*) snrdb
call getarg(6,arg)
read(arg,*) nfiles
!sig is the peak amplitude of the ping.
sig=sqrt(2.0)*10.0**(0.05*snrdb)
h=default_header(12000,NMAX)
i1=len(trim(msg))-5
ichk=0
itype=1
call genmsk_128_90(msg,ichk,msgsent,itone,itype)
twopi=8.d0*atan(1.d0)
nsym=144
nsps=6*nslow
if( itone(41) .lt. 0 ) nsym=40
baud=2000.d0/nslow
dphi0=twopi*(freq-0.25d0*baud)/12000.d0
dphi1=twopi*(freq+0.25d0*baud)/12000.d0
phi=0.0
k=0
nreps=NMAX/(nsym*nsps)
print*,nsym,nslow,nsps,baud,freq
do jrep=1,nreps
do i=1,nsym
if( itone(i) .eq. 0 ) then
dphi=dphi0
else
dphi=dphi1
endif
do j=1,nsps
waveform(k)=cos(phi)
k=k+1
phi=mod(phi+dphi,twopi)
enddo
enddo
enddo
if(itype.lt.1 .or. itype.gt.7) then
print*,'Illegal message'
go to 999
endif
if(nslow.eq.1) call makepings(pings,NMAX,width,sig)
! call sgran()
do ifile=1,nfiles !Loop over requested number of files
write(fname,1002) ifile !Output filename
1002 format('000000_',i6.6)
open(10,file=fname(1:13)//'.wav',access='stream',status='unknown')
wave=0.0
iwave=0
fac=sqrt(6000.0/2500.0)
do i=0,NMAX-1
xx=gran()
if(nslow.eq.1) wave(i)=pings(i)*waveform(i) + fac*xx
if(nslow.gt.1) wave(i)=sig*waveform(i) + fac*xx
iwave(i)=30.0*wave(i)
enddo
write(10) h,iwave !Save the .wav file
close(10)
enddo
999 end program msk144sim