WSJT-X/lib/jt9.f90

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3.7 KiB
Fortran
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program jt9
! Decoder for JT9. Can run stand-alone, reading data from *.wav files;
! or as the back end of wsjt-x, with data placed in a shared memory region.
! NB: For unknown reason, ***MUST*** be compiled by g95 with -O0 !!!
character*80 arg,infile
parameter (NMAX=1800*12000) !Total sample intervals per 30 minutes
parameter (NDMAX=1800*1500) !Sample intervals at 1500 Hz rate
parameter (NSMAX=22000) !Max length of saved spectra
integer*4 ihdr(11)
real*4 s(NSMAX)
real*4 ccfred(NSMAX)
logical*1 lstrong(0:1023)
integer*1 i1SoftSymbols(207)
character*22 msg
character*33 line
integer*2 id2
complex c0(NDMAX)
common/jt9com/ss(184,NSMAX),savg(NSMAX),id2(NMAX),nutc,ndiskdat, &
ntr,mousefqso,newdat,nfa,nfb,ntol,kin
nargs=iargc()
if(nargs.lt.1) then
print*,'Usage: jt9 TRperiod file1 [file2 ...]'
print*,' Reads data from *.wav files.'
print*,''
print*,' jt9 -s'
print*,' Gets data from shared memory region.'
go to 999
endif
call getarg(1,arg)
if(arg(1:2).eq.'-s') go to 999
read(arg,*) ntrperiod
ifile1=2
nfa=1000
nfb=2000
! ntol=500
ntol=500
nfqso=1500
newdat=1
nb=0
nbslider=100
limit=20000
ndiskdat=1
do ifile=ifile1,nargs
call getarg(ifile,infile)
open(10,file=infile,access='stream',status='old',err=998)
read(10) ihdr
i1=index(infile,'.wav')
read(infile(i1-4:i1-1),*,err=1) nutc0
go to 2
1 nutc0=0
2 nsps=0
if(ntrperiod.eq.1) nsps=6912
if(ntrperiod.eq.2) nsps=15360
if(ntrperiod.eq.5) nsps=40960
if(ntrperiod.eq.10) nsps=82944
if(ntrperiod.eq.30) nsps=252000
if(nsps.eq.0) stop 'Error: bad TRperiod'
kstep=nsps/2
tstep=kstep/12000.0
k=0
nhsym0=-999
npts=(60*ntrperiod-6)*12000
! do i=1,npts
! id2(i)=100.0*sin(6.283185307*1600.0*i/12000.0)
! enddo
do iblk=1,npts/kstep
k=iblk*kstep
read(10,end=10) id2(k-kstep+1:k)
nhsym=(k-2048)/kstep
if(nhsym.ge.1 .and. nhsym.ne.nhsym0) then
! Emit signal readyForFFT
ingain=0
call symspec(k,ntrperiod,nsps,ingain,nb,nbslider,pxdb, &
s,ccfred,df3,ihsym,nzap,slimit,lstrong,c0,npts8)
nhsym0=nhsym
if(ihsym.ge.184) go to 10
endif
enddo
10 close(10)
iz=1000.0/df3
nutc=nutc0
call sync9(ss,tstep,df3,ntol,nfqso,ccfred,ia,ib,ipk) !Get sync, freq
fgood=0.
df8=1500.0/(nsps/8)
sbest=0.
do i=ia,ib
f=(i-1)*df3
if((i.eq.ipk .or. ccfred(i).ge.3.0) .and. f.gt.fgood+10.0*df8) then
call spec9(c0,npts8,nsps,f,fpk,xdt,snrdb,i1SoftSymbols)
call decode9(i1SoftSymbols,limit,nlim,msg)
snr=snrdb
sync=ccfred(i) - 2.0
if(sync.lt.0.0) sync=0.0
nsync=sync
if(nsync.gt.10) nsync=10
nsnr=nint(snr)
width=0.0
if(ccfred(i).gt.sbest .and. fgood.eq.0.0) then
sbest=ccfred(i)
write(line,1010) nutc,nsync,nsnr,xdt,1000.0+fpk,width
if(nsync.gt.0) nsynced=1
endif
if(msg.ne.' ') then
write(*,1010) nutc,nsync,nsnr,xdt,1000.0+fpk,width,msg
1010 format(i4.4,i4,i5,f6.1,f8.2,f6.2,3x,a22)
fgood=f
nsynced=1
ndecoded=1
endif
endif
enddo
if(fgood.eq.0.0) then
write(*,1020) line
1020 format(a33)
endif
enddo
go to 999
998 print*,'Cannot open file:'
print*,infile
999 end program jt9