WSJT-X/lib/qra02.f90
Joe Taylor deb89de196 Temporary (partial?) workaround for qra decoder bug.
git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@6835 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
2016-06-30 23:17:40 +00:00

154 lines
3.3 KiB
Fortran

subroutine qra02(dd,nf1,nf2,nfqso,ntol,mycall_12,sync,nsnr,dtx,nfreq, &
decoded,nft)
use packjt
parameter (NFFT=2*6912,NH=NFFT/2,NZ=5760)
character decoded*22,mycall_12*12,mycall*6
character*1 mark(0:5),zplot(0:63)
logical ltext
integer icos7(0:6)
integer ipk(1)
integer jpk(1)
! integer dat4(12)
integer dat4(120)
real dd(60*12000)
real s(NZ)
real savg(NZ)
real blue(0:25)
real red(NZ)
real x(NFFT)
complex cx(0:NH)
equivalence (x,cx)
data icos7/2,5,6,0,4,1,3/ !Costas 7x7 pattern
data mark/' ','.','-','+','X','$'/
common/qra65com/ss(NZ,194),s3(0:63,1:63),ccf(NZ,0:25)
save
! rewind 74
! rewind 75
! print*,'B',nf1,nf2,nfqso,ntol
nsps=6912
istep=nsps/2
nsteps=52*12000/istep - 2
ia=1-istep
savg=0.
df=12000.0/NFFT
do j=1,nsteps
ia=ia+istep
ib=ia+nsps-1
x(1:nsps)=1.2e-4*dd(ia:ib)
x(nsps+1:)=0.0
call four2a(x,nfft,1,-1,0) !r2c FFT
do i=1,NZ
s(i)=real(cx(i))**2 + aimag(cx(i))**2
enddo
ss(1:NZ,j)=s
savg=savg+s
enddo
savg=savg/nsteps
call pctile(savg,NZ,45,base)
savg=savg/base - 1.0
ss=ss/base
! do i=1,NZ
! write(73,1010) i*df,savg(i),i
!1010 format(2f10.3,i8)
! enddo
fa=max(nf1,nfqso-ntol)
fb=min(nf2,nfqso+ntol)
ia=nint(fa/df)
ib=nint(fb/df)
fac=1.0/sqrt(21.0)
sync=0.
do if0=ia,ib
red(if0)=0.
do j=0,25
t=-3.0
do n=0,6
i=if0 + 2*icos7(n)
t=t + ss(i,1+2*n+j) + ss(i,1+2*n+j+78) + ss(i,1+2*n+j+154)
enddo
ccf(if0,j)=fac*t
if(ccf(if0,j).gt.red(if0)) then
red(if0)=ccf(if0,j)
if(red(if0).gt.sync) then
sync=red(if0)
f0=if0*df
dtx=j*istep/12000.0 - 1.0
i0=if0
j0=j
endif
endif
enddo
enddo
do i=0,63
k=i0 + 2*i
jj=j0+13
do j=1,63
jj=jj+2
s3(i,j)=ss(k,jj)
if(j.eq.32) jj=jj+14 !Skip over the middle Costas array
enddo
enddo
do j=1,63
do i=0,63
n=0.25*s3(i,j)
if(n.lt.0) n=0
if(n.gt.5) n=5
zplot(i)=mark(n)
enddo
ipk=maxloc(s3(0:63,j))
! write(76,3001) j,zplot,ipk(1)-1
!3001 format(i2,1x,'|',64a1,'|',i4)
enddo
if0=nint(f0/df)
nfreq=nint(f0)
blue(0:25)=ccf(if0,0:25)
jpk=maxloc(blue)
xpk=jpk(1) + 1.0
call slope(blue,26,xpk)
! do j=0,25
! tsec=j*istep/12000.0
! write(74,1020) tsec,blue(j)
!1020 format(f5.2,i3,10f7.1)
! enddo
! do i=ia,ib
! f=i*df
! write(75,1030) f,red(i)
!1030 format(2f10.2)
! enddo
! flush(74)
! flush(75)
! flush(76)
decoded=' '
nft=100
nsnr=-30
if(sync.gt.1.0) nsnr=nint(10.0*log10(sync) - 38.0)
if(sync.lt.12.8) go to 900 !### Temporary ###
! print*,'A',sync,nsnr
mycall=mycall_12(1:6) !### May need fixing ###
call packcall(mycall,nmycall,ltext)
! write(77,3002) s3
!3002 format(f10.3)
! flush(77)
! print*,'a',sync,dtx,base
call qra65_dec(s3,nmycall,dat4,irc) !Attempt decoding
! print*,'z',sync,dtx,nfreq
if(irc.ge.0) then
call unpackmsg(dat4,decoded) !Unpack the user message
call fmtmsg(decoded,iz)
nft=100 + irc
endif
900 return
end subroutine qra02