WSJT-X/lib/sync9.f90
Joe Taylor 5e459fe07a Compute ccfred, the "red curve".
git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@2655 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
2012-10-10 20:40:46 +00:00

60 lines
1.5 KiB
Fortran

subroutine sync9(ss,tstep,f0a,df3,ntol,nfqso,sync,fpk,ccfred)
parameter (NSMAX=22000) !Max length of saved spectra
real ss(184,NSMAX)
real ccfred(NSMAX)
integer ii0(16)
integer ii(16) !Locations of sync half-symbols
data ii/1,11,21,31,41,51,61,77,89,101,113,125,137,149,161,169/
integer isync(85) !Sync vector for half-symbols
data isync/ &
1,0,0,0,0,1,0,0,0,0,1,0,0,0,0,1,0,0,0,0, &
1,0,0,0,0,1,0,0,0,0,1,0,0,0,0,0,0,0,1,0, &
0,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,1,0,0,0, &
0,0,1,0,0,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0, &
1,0,0,0,1/
ia=1
ib=min(1000,nint(1000.0/df3))
if(ntol.lt.1000) then
ia=nint((nfqso-1000-ntol)/df3)
ib=nint((nfqso-1000+ntol)/df3)
if(ia.lt.1) ia=1
if(ib.gt.NSMAX) ib=NSMAX
endif
print*,ia,ib,df3*ia+1000,df3*ib+1000
sbest=0.
lagmax=2.5/tstep + 0.9999
ccfred=0.
do i=ia,ib
smax=0.
do lag=-lagmax,lagmax
sum=0.
do j=1,16
k=ii(j) + lag
if(k.ge.1) sum=sum + ss(k,i)
enddo
if(sum.gt.smax) then
smax=sum
ipk=i
lagpk=lag
endif
enddo
if(smax.gt.sbest) then
sbest=smax
ipkbest=ipk
lagpkbest=lagpk
endif
ccfred(i)=smax
enddo
fpk=f0a + (ipkbest-1)*df3
sync=sbest
return
end subroutine sync9