WSJT-X/lib/peakdf9.f90
Joe Taylor 411c9422e7 Decoded text now appears in main window. However, ... the next decode
request fails.  Then 3rd one is OK, 4th fails, etc., etc.


git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@2669 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
2012-10-16 23:32:15 +00:00

34 lines
809 B
Fortran

subroutine peakdf9(c0,npts8,nsps8,istart,foffset,idfpk)
complex c0(0:npts8-1)
complex zsum
integer ii(16) !Locations of sync symbols
data ii/1,6,11,16,21,26,31,39,45,51,57,63,69,75,81,85/
twopi=8.0*atan(1.0)
df=1500.0/nsps8
smax=0.
do idf=-5,5
f0=foffset + 0.1*df*idf
dphi=twopi*f0/1500.0
sum=0.
do j=1,16
i1=(ii(j)-1)*nsps8 + istart
phi=0.
zsum=0.
do i=i1,i1+nsps8-1
if(i.lt.0 .or. i.gt.npts8-1) cycle
phi=phi + dphi
zsum=zsum + c0(i) * cmplx(cos(phi),-sin(phi))
enddo
sum=sum + real(zsum)**2 + aimag(zsum)**2
enddo
if(sum.gt.smax) then
idfpk=idf
smax=sum
endif
enddo
return
end subroutine peakdf9