mirror of
https://github.com/saitohirga/WSJT-X.git
synced 2024-11-01 08:07:10 -04:00
5c21f6806d
2. ft8d is now a bare-bones multi-decoder. 3. wsjt-x now includes the bare-bones multi-decoder for FT8. git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@7729 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
92 lines
1.9 KiB
Fortran
92 lines
1.9 KiB
Fortran
subroutine sync8(iwave,s,candidate,ncand)
|
|
|
|
include 'ft8_params.f90'
|
|
parameter (JZ=20)
|
|
complex cx(0:NH1)
|
|
real s(NH1,NHSYM)
|
|
real savg(NH1)
|
|
real x(NFFT1)
|
|
real sync2d(NH1,-JZ:JZ)
|
|
real red(NH1)
|
|
real candidate(3,100)
|
|
integer*2 iwave(NMAX)
|
|
integer jpeak(NH1)
|
|
integer indx(NH1)
|
|
integer ii(1)
|
|
integer icos7(0:6)
|
|
data icos7/2,5,6,0,4,1,3/ !Costas 7x7 tone pattern
|
|
equivalence (x,cx)
|
|
|
|
! Compute symbol spectra at half-symbol steps.
|
|
savg=0.
|
|
istep=NSPS/2
|
|
tstep=istep/12000.0
|
|
df=12000.0/NFFT1
|
|
|
|
fac=1.0/300.0
|
|
do j=1,NHSYM
|
|
ia=(j-1)*istep + 1
|
|
ib=ia+NSPS-1
|
|
x(1:NSPS)=fac*iwave(ia:ib)
|
|
x(NSPS+1:)=0.
|
|
call four2a(x,NFFT1,1,-1,0) !r2c FFT
|
|
do i=1,NH1
|
|
s(i,j)=real(cx(i))**2 + aimag(cx(i))**2
|
|
enddo
|
|
savg=savg + s(1:NH1,j)
|
|
enddo
|
|
|
|
ia=nint(200.0/df)
|
|
ib=nint(4000.0/df)
|
|
savg=savg/NHSYM
|
|
|
|
do i=ia,ib
|
|
do j=-JZ,JZ
|
|
t=0.
|
|
do n=0,6
|
|
k=j+2*n
|
|
if(k.ge.1) t=t + s(i+2*icos7(n),k)
|
|
t=t + s(i+2*icos7(n),k+72)
|
|
if(k+144.le.NHSYM) t=t + s(i+2*icos7(n),k+144)
|
|
enddo
|
|
sync2d(i,j)=t
|
|
enddo
|
|
enddo
|
|
|
|
red=0.
|
|
do i=ia,ib
|
|
ii=maxloc(sync2d(i,-JZ:JZ)) - 1 - JZ
|
|
j0=ii(1)
|
|
jpeak(i)=j0
|
|
red(i)=sync2d(i,j0)
|
|
enddo
|
|
iz=ib-ia+1
|
|
call indexx(red(ia:ib),iz,indx)
|
|
ibase=indx(nint(0.40*iz)) - 1 + ia
|
|
base=red(ibase)
|
|
red=red/base
|
|
|
|
candidate=0.
|
|
k=0
|
|
do i=1,100
|
|
n=ia + indx(iz+1-i) - 1
|
|
if(red(n).lt.2.0) exit
|
|
do j=1,k !Eliminate near-dupe freqs
|
|
f=n*df
|
|
if(abs(f-candidate(1,j)).lt.3.0) go to 10
|
|
enddo
|
|
k=k+1
|
|
candidate(1,k)=n*df
|
|
candidate(2,k)=(jpeak(n)-1)*tstep
|
|
candidate(3,k)=red(n)
|
|
! write(*,3024) k,candidate(1:3,k)
|
|
!3024 format(i3,3f10.2)
|
|
10 continue
|
|
enddo
|
|
ncand=k
|
|
fac=20.0/maxval(s)
|
|
s=fac*s
|
|
|
|
return
|
|
end subroutine sync8
|