mirror of
https://github.com/saitohirga/WSJT-X.git
synced 2024-11-18 10:01:57 -05:00
357f467ef0
git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/jtms3@2529 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
73 lines
2.4 KiB
Fortran
73 lines
2.4 KiB
Fortran
subroutine jtmsk(dat,npts,cfile6,tpk,mswidth,ndb,nrpt,Nfreeze, &
|
|
ntol,MouseDF,pick,mycall)
|
|
|
|
! Decode a JTMSK ping
|
|
|
|
parameter (NZ=2*48000)
|
|
real dat(npts) !Raw data
|
|
complex cdat(NZ) !Analytic form of signal
|
|
character*6 cfile6 !FileID
|
|
logical pick
|
|
character*12 mycall
|
|
real s(NZ) !Power spectrum
|
|
real s2(0:63,400)
|
|
real r(60000)
|
|
complex cw(168,0:63) !Complex waveforms for all codewords
|
|
complex cwb(168) !Complex waveform for <space>
|
|
logical first
|
|
character msg*400,msg29*29
|
|
data first/.true./
|
|
save first,cw,cwb
|
|
save cdat !Fix its address, for four2
|
|
|
|
if(first) call setupmsk(cw,cwb) !Calculate waveforms for codewords
|
|
first=.false.
|
|
|
|
nsps=24 !Samples per symbol
|
|
f0=1000.0 !Nominal frequency for bit=0
|
|
n=log(float(npts))/log(2.0) + 1.0
|
|
nfft1=2**n !FFT length
|
|
call analytic(dat,npts,nfft1,s,cdat) !Convert to analytic signal
|
|
|
|
call mskdf(cdat,npts,tpk,nfft1,f0,nfreeze,mousedf,ntol, &
|
|
dfx,snrsq2) !Get DF
|
|
sq2lim=7.0
|
|
if(pick) sq2lim=5.0
|
|
if(snrsq2.lt.sq2lim) go to 900 !Reject non-JTMS signals
|
|
|
|
call tweak1(cdat,npts,-dfx,cdat) !Mix to standard frequency
|
|
|
|
call syncmsk(cdat,npts,cwb,r,i1) !Get character sync
|
|
|
|
call lenmsk(r,npts,msglen) !Find message length
|
|
|
|
s2=0.
|
|
nchar=(npts-168+1-i1)/168
|
|
if(nchar.gt.400) nchar=400
|
|
|
|
call decodemsk(cdat,npts,cw,i1,nchar,s2,msg) !Decode the message
|
|
|
|
ia=1
|
|
if(nchar.ge.40) ia=min(nchar/3,nchar-28)
|
|
ib=min(ia+28,nchar) !Can better limits ia, ib be found?
|
|
msg29=adjustl(msg(ia:ib))
|
|
msg=adjustl(msg)
|
|
ib=min(nchar,45)
|
|
ndf=nint(dfx)
|
|
nchk=max(20,nint(1.5*msglen))
|
|
|
|
if(msglen.eq.0 .or. nchar.lt.nchk .or. pick) then
|
|
write(*,1110) cfile6,tpk,mswidth,ndb,nrpt,ndf,msg(1:45)
|
|
1110 format(a6,f5.1,i5,i3,1x,i2.2,i5,5x,a45)
|
|
endif
|
|
|
|
if(msglen.gt.0 .and. nchar.ge.nchk) then
|
|
call foldmsk(s2,msglen,nchar,mycall,msg,msg29) !Decode folded message
|
|
write(*,1120) cfile6,tpk,mswidth,ndb,nrpt,ndf,msg29
|
|
1120 format(a6,f5.1,i5,i3,1x,i2.2,i5,5x,a29,11x,'*')
|
|
endif
|
|
|
|
900 continue
|
|
return
|
|
end subroutine jtmsk
|