WSJT-X/lib/wsjt4.f90

181 lines
4.5 KiB
Fortran
Raw Normal View History

subroutine wsjt4(dat,npts,nutc,NClearAve,minsync,ntol,emedelay,dttol, &
mode4,minw,mycall,hiscall,hisgrid,nfqso,NAgain,ndepth,neme)
! Orchestrates the process of decoding JT4 messages, using data that
! have been 2x downsampled.
! NB: JT4 presently looks for only one decodable signal in the FTol
! range -- analogous to the nqd=1 step in JT9 and JT65.
use jt4
real dat(npts) !Raw data
real z(458,65)
logical first,prtavg
character decoded*22,special*5
character*22 avemsg,deepmsg,deepave,blank,deepmsg0,deepave1
character csync*1,cqual*2
character*12 mycall
character*12 hiscall
character*6 hisgrid
data first/.true./,nutc0/-999/,nfreq0/-999999/
save
if(first) then
nsave=0
first=.false.
blank=' '
ccfblue=0.
ccfred=0.
nagain=0
endif
zz=0.
syncmin=3.0 + minsync
naggressive=0
if(ndepth.ge.2) naggressive=1
nq1=3
nq2=6
if(naggressive.eq.1) nq1=1
if(NClearAve.ne.0) then
nsave=0
iutc=-1
nfsave=0.
listutc=0
ppsave=0.
rsymbol=0.
dtsave=0.
syncsave=0.
nfanoave=0
ndeepave=0
endif
! Attempt to synchronize: look for sync pattern, get DF and DT.
call timer('sync4 ',0)
call sync4(dat,npts,mode4,minw)
call timer('sync4 ',1)
call timer('zplt ',0)
do ich=4,7
z(1:458,1:65)=zz(274:731,1:65,ich)
call zplt(z,ich-4,syncz,dtxz,nfreqz,flipz,sync2z,0,emedelay,dttol, &
nfqso,ntol)
if(ich.eq.5) then
dtxzz=dtxz
nfreqzz=nfreqz
endif
enddo
call timer('zplt ',1)
! Use results from zplt
flip=flipz
sync=syncz
snrx=db(sync) - 26.
nsnr=nint(snrx)
if(sync.lt.syncmin) then
write(*,1010) nutc,nsnr,dtxz,nfreqz
go to 990
endif
! We have achieved sync
decoded=blank
deepmsg=blank
special=' '
nsync=sync
nsnrlim=-33
csync='*'
if(flip.lt.0.0) csync='#'
qbest=0.
qabest=0.
prtavg=.false.
do idt=-2,2
dtx=dtxz + 0.03*idt
nfreq=nfreqz + 2*idf
! Attempt a single-sequence decode, including deep4 if Fano fails.
call timer('decode4 ',0)
call decode4(dat,npts,dtx,nfreq,flip,mode4,ndepth,neme,minw, &
mycall,hiscall,hisgrid,decoded,nfano,deepmsg,qual,ich)
call timer('decode4 ',1)
if(nfano.gt.0) then
! Fano succeeded: display the message and return FANO OK
write(*,1010) nutc,nsnr,dtx,nfreq,csync,decoded,' *', &
char(ichar('A')+ich-1)
1010 format(i4.4,i4,f5.2,i5,1x,a1,1x,a22,a2,1x,a1,i3)
nsave=0
go to 990
else ! NO FANO
if(qual.gt.qbest) then
dtx0=dtx
nfreq0=nfreq
deepmsg0=deepmsg
ich0=ich
qbest=qual
endif
endif
if(idt.ne.0) cycle
! Single-sequence Fano decode failed, so try for an average Fano decode:
qave=0.
! If this is a new minute or a new frequency, call avg4
if(.not. prtavg) then
if(nutc.ne.nutc0 .or. abs(nfreq-nfreq0).gt.ntol) then
nutc0=nutc ! TRY AVG
nfreq0=nfreq
nsave=nsave+1
nsave=mod(nsave-1,64)+1
call timer('avg4 ',0)
call avg4(nutc,sync,dtx,flip,nfreq,mode4,ntol,ndepth,neme, &
mycall,hiscall,hisgrid,nfanoave,avemsg,qave,deepave,ich, &
ndeepave)
call timer('avg4 ',1)
endif
if(nfanoave.gt.0) then
! Fano succeeded: display the message AVG FANO OK
write(*,1010) nutc,nsnr,dtx,nfreq,csync,avemsg,' *', &
char(ichar('A')+ich-1),nfanoave
prtavg=.true.
cycle
else
if(qave.gt.qabest) then
dtx1=dtx
nfreq1=nfreq
deepave1=deepave
ich1=ich
qabest=qave
endif
endif
endif
enddo
dtx=dtx0
nfreq=nfreq0
deepmsg=deepmsg0
ich=ich0
qual=qbest
if(int(qual).ge.nq1) then
write(cqual,'(i2)') int(qual)
write(*,1010) nutc,nsnr,dtx,nfreq,csync, &
deepmsg,cqual,char(ichar('A')+ich-1)
else
write(*,1010) nutc,nsnr,dtxz,nfreqz,csync
endif
dtx=dtx1
nfreq=nfreq1
deepave=deepave1
ich=ich1
qave=qabest
if(int(qave).ge.nq1) then
write(cqual,'(i2)') nint(qave)
write(*,1010) nutc,nsnr,dtx,nfreq,csync, &
deepave,cqual,char(ichar('A')+ich-1),ndeepave
endif
990 return
end subroutine wsjt4