WSJT-X/map65a.f90

subroutine map65a

!  Processes timf2 data from Linrad to find and decode JT65 signals.

  parameter (MAXMSG=1000)            !Size of decoded message list
  parameter (NFFT=32768)             !Half symbol = 17833 samples;
  real savg(4,NFFT)
  real tavg(-50:50)                  !Temp for finding local base level
  real base(4)                       !Local basel level at 4 pol'ns
  real tmp (200)                     !Temp storage for pctile sorting
  real short(3,NFFT)                 !SNR dt ipol for potential shorthands
  real sig(MAXMSG,30)                !Parameters of detected signals
  real a(5)
  character*22 msg(MAXMSG)
  character*3 shmsg0(4),shmsg
  integer indx(MAXMSG),nsiz(MAXMSG)
  logical done(MAXMSG)
  character decoded*22,blank*22
  parameter (NSMAX=60*96000)          !Samples per 60 s file
  integer*2 id(4,NSMAX)               !46 MB: raw data from Linrad timf2
  common/datcom/nutc,newdat2,id
  common/spcom/ip0,ss(4,322,NFFT)                !169 MB: half-symbol spectra
  data blank/'                      '/
  data shmsg0/'ATT','RO ','RRR','73 '/
  data nfile/0/,nutc0/-999/,nid/0/
  save

  include 'gcom2.f90'

  if(newdat2.gt.0) nid=1
  if(nid.eq.0) go to 999
  rewind 11
  rewind 12
  if(nutc.ne.nutc0) nfile=nfile+1
  nutc0=nutc
  nutcdata=nutc
  write(utcdata,1001) nutc
1001 format(i4.4)
  utcdata=utcdata(1:2)//':'//utcdata(3:4)

  tskip=0.
!  fselect=126.0 + 1.6 + 0.290
!  nflip=-1
!  ip0=1
  fselect=128.0 + 1.6 + 0.220               !AA1YN
  nflip=1
  ip0=3
!  fselect=155.0 + 1.6 + 0.454
!  nflip=1
!  ip0=2
!  fselect=103 + 1.6 - 0.07
!  nflip=-1                     !May need to try both +/- 1
!  ip0=4                       !Try all four?

  open(23,file='CALL3.TXT',status='unknown')

  df=96000.0/NFFT                    !df = 96000/NFFT = 2.930 Hz
  fa=0.0
  fb=60000.0
  ia=nint((fa+23000.0)/df + 1.0)     ! 23000 = 48000 - 25000
  ib=nint((fb+23000.0)/df + 1.0)
  ftol=0.020                          !Frequency tolerance (kHz)
  kk=0
  nkk=1

  nz=n/8
  if(fselect.gt.0.0) then

!  nfilt=2 should be faster (but doesn't work right?)
     nfilt=2                      !nfilt=2 is faster for selected freq
     freq=fselect
     dt=2.314240                  !Not needed?
     call decode1a(id,newdat2,nfilt,freq,nflip,ip0,sync2,        &
          a,dt,pol,nkv,nhist,qual,decoded)
     nsync1=0
     nsync2=nint(10.0*log10(sync2)) - 40 !### empirical ###
     ndf=nint(a(1))
     nw=0

!  Insert 'OOO' if flip<0.
!     write(11,1010) nutc,nsync2,dt,ndf,nw,decoded,nkv,nqual
!1010 format(i4.4,i4,f5.1,i5,i3,2x,a22,2i3)
     nkHz=nint(freq-1.600)
     npol=45*(ipol-1)
     write(11,1010) nkHz,ndf,npol,nutc,nsync2,dt,nw,decoded,nkv,nqual
1010 format(i3,i5,i4,i5.4,i4,f5.1,i3,2x,a22,2i3)
     ndecdone=1
  endif
  if(newdat2.eq.0) go to 999

  nfilt=1
  do i=1,NFFT
     short(1,i)=0.
     short(2,i)=0.
     short(3,i)=0.
  enddo

  call symspec(id,nz,ss,savg)
  newspec=1
     
  freq0=-999.
  sync10=-999.
  fshort0=-999.
  sync20=-999.
  ntry=0
  do i=ia,ib                               !Search over freq range
     freq=0.001*((i-1)*df - 23000) + 100.0

!  Find the local base level for each polarization; update every 10 bins.
     if(mod(i-ia,10).eq.0) then
        do jp=1,4
           do ii=-50,50
              tavg(ii)=savg(jp,i+ii)
           enddo
           call pctile(tavg,tmp,101,50,base(jp))
        enddo
     endif

!  Find max signal at this frequency
     smax=0.
     do jp=1,4
        if(savg(jp,i)/base(jp).gt.smax) smax=savg(jp,i)/base(jp)
     enddo

     if(smax.gt.1.1) then
        ntry=ntry+1
!  Look for JT65 sync patterns and shorthand square-wave patterns.
        call ccf65(ss(1,1,i),sync1,ipol,dt,flipk,                  &
             syncshort,snr2,ipol2,dt2)

        shmsg='   '
!  Is there a shorthand tone above threshold?
        if(syncshort.gt.1.0) then
              
! ### Do shorthand AFC here (or maybe after finding a pair?) ###

           short(1,i)=syncshort
           short(2,i)=dt2
           short(3,i)=ipol2
!  Check to see if lower tone of shorthand pair was found.
           do j=2,4
              i0=i-nint(j*53.8330078/df)
!  Should this be i0 +/- 1, or just i0?
!  Should we also insist that difference in DT be either 1.5 or -1.5 s?
              if(short(1,i0).gt.1.0) then
                 fshort=0.001*((i0-1)*df - 23000) + 100.0

!  Keep only the best candidate within ftol.
                 if(fshort-fshort0.le.ftol .and. sync2.gt.sync20    &
                      .and. nkk.eq.2) kk=kk-1
                 if(fshort-fshort0.gt.ftol .or.                     &
                      sync2.gt.sync20) then
                    kk=kk+1
                    sig(kk,1)=nfile
                    sig(kk,2)=nutc
                    sig(kk,3)=fshort
                    sig(kk,4)=syncshort
                    sig(kk,5)=dt2
                    sig(kk,6)=45*(ipol2-1)/57.2957795
                    sig(kk,7)=0
                    sig(kk,8)=snr2
                    sig(kk,9)=0
                    sig(kk,10)=0
!                           sig(kk,11)=rms0
                    sig(kk,12)=savg(ipol2,i)
                    sig(kk,13)=0
                    sig(kk,14)=0
                    sig(kk,15)=0
                    sig(kk,16)=0
!                           sig(kk,17)=0
                    sig(kk,18)=0
                    msg(kk)=shmsg0(j)
                    fshort0=fshort
                    sync20=sync2
                    nkk=2
                 endif
              endif
           enddo
        endif
        
!  Is sync1 above threshold?
        if(sync1.gt.1.0) then

!  Keep only the best candidate within ftol.
!  (Am I deleting any good decodes by doing this?  Any harm in omitting
!  these statements??)
           if(freq-freq0.le.ftol .and. sync1.gt.sync10 .and.         &
                nkk.eq.1) kk=kk-1

           if(freq-freq0.gt.ftol .or. sync1.gt.sync10) then
              nflip=nint(flipk)
              call decode1a(id,newdat2,nfilt,freq,nflip,ipol,         &
                   sync2,a,dt,pol,nkv,nhist,qual,decoded)
!              i9=index(decoded,'AA1YN')
!              if(i9.gt.0) print*,i,i9,fselect,freq,decoded
              kk=kk+1
              sig(kk,1)=nfile
              sig(kk,2)=nutc
              sig(kk,3)=freq
              sig(kk,4)=sync1
              sig(kk,5)=dt
              sig(kk,6)=pol
              sig(kk,7)=flipk
              sig(kk,8)=sync2
              sig(kk,9)=nkv
              sig(kk,10)=qual
!                     sig(kk,11)=rms0                  
              sig(kk,12)=savg(ipol,i)
              sig(kk,13)=a(1)
              sig(kk,14)=a(2)
              sig(kk,15)=a(3)
              sig(kk,16)=a(4)
!                     sig(kk,17)=a(5)
              sig(kk,18)=nhist
              msg(kk)=decoded
              freq0=freq
              sync10=sync1
              nkk=1
           endif
        endif
     endif
  enddo

!         write(*,1010)

!  Trim the list and produce a sorted index and sizes of groups.
!  (Should trimlist remove all but best SNR for given UTC and message content?)
  call trimlist(sig,kk,indx,nsiz,nz)

  do i=1,kk
     done(i)=.false.
  enddo
  j=0
  ilatest=-1
  do n=1,nz
     ifile0=0
     do m=1,nsiz(n)
        i=indx(j+m)
        ifile=sig(i,1)
        if(ifile.gt.ifile0 .and.msg(i).ne.blank) then
           ilatest=i
           ifile0=ifile
        endif
     enddo
     i=ilatest

     if(i.ge.1) then
        if(.not.done(i)) then
           done(i)=.true.
           nutc=sig(i,2)
           freq=sig(i,3)
           sync1=sig(i,4)
           dt=sig(i,5)
           npol=nint(57.2957795*sig(i,6))
           flip=sig(i,7)
           sync2=sig(i,8)
           nkv=sig(i,9)
           nqual=min(sig(i,10),10.0)
!                  rms0=sig(i,11)
           nsavg=sig(i,12)                   !Was used for diagnostic ...
           do k=1,5
              a(k)=sig(i,12+k)
           enddo
           nhist=sig(i,18)
           decoded=msg(i)
           
           if(flip.lt.0.0) then
              do i=22,1,-1
                 if(decoded(i:i).ne.' ') go to 10
              enddo
              stop 'Error in message format'
10            if(i.le.18) decoded(i+2:i+4)='OOO'
           endif
           nkHz=nint(freq-1.600)
           f0=144.0+0.001*nkHz
           ndf=nint(1000.0*(freq-1.600-nkHz))
           ndf0=nint(a(1))
           ndf1=nint(a(2))
           ndf2=nint(a(3))
           nsync1=sync1
           nsync2=nint(10.0*log10(sync2)) - 40 !### empirical ###
           write(26,1014) f0,ndf,ndf0,ndf1,ndf2,dt,npol,nsync1,       &
                nsync2,nutc,decoded,nkv,nqual,nhist
1014       format(f7.3,i5,3i3,f5.1,i5,i3,i4,i5.4,2x,a22,3i3)

        endif
     endif
     j=j+nsiz(n)
  enddo
  call display
  ndecdone=2
    
999 return
end subroutine map65a