mirror of
https://github.com/saitohirga/WSJT-X.git
synced 2024-11-03 16:01:18 -05:00
103 lines
2.3 KiB
Fortran
103 lines
2.3 KiB
Fortran
|
subroutine msk144sync(cdat,n,ntol,ndf,iavmask,npeaks,fest,snr,ipklocs,pkamps,c)
|
||
|
|
|
||
|
|
parameter (NSPM=864)
|
||
|
|
complex cdat(n)
|
||
|
|
complex cdat2(n)
|
||
|
|
complex c(NSPM) !Coherently averaged complex data
|
||
|
|
complex ct2(2*NSPM)
|
||
|
|
complex cs(NSPM)
|
||
|
|
complex cb(42) !Complex waveform for sync word
|
||
|
|
complex cc(0:NSPM-1)
|
||
|
|
|
||
|
|
integer s8(8)
|
||
|
|
integer iloc(1)
|
||
|
|
integer ipklocs(npeaks)
|
||
|
|
integer iavmask(8) ! defines which frames to average
|
||
|
|
|
||
|
|
real cbi(42),cbq(42)
|
||
|
|
real pkamps(npeaks)
|
||
|
|
real xcc(0:NSPM-1)
|
||
|
|
real xccs(0:NSPM-1)
|
||
|
|
real pp(12) !Half-sine pulse shape
|
||
|
|
logical first
|
||
|
|
data first/.true./
|
||
|
|
data s8/0,1,1,1,0,0,1,0/
|
||
|
|
save first,cb,fs,pi,twopi,dt,s8,pp
|
||
|
|
|
||
|
|
! call system_clock(count0,clkfreq)
|
||
|
|
if(first) then
|
||
|
|
pi=4.0*atan(1.0)
|
||
|
|
twopi=8.0*atan(1.0)
|
||
|
|
fs=12000.0
|
||
|
|
dt=1.0/fs
|
||
|
|
|
||
|
|
do i=1,12 !Define half-sine pulse
|
||
|
|
angle=(i-1)*pi/12.0
|
||
|
|
pp(i)=sin(angle)
|
||
|
|
enddo
|
||
|
|
|
||
|
|
! Define the sync word waveforms
|
||
|
|
s8=2*s8-1
|
||
|
|
cbq(1:6)=pp(7:12)*s8(1)
|
||
|
|
cbq(7:18)=pp*s8(3)
|
||
|
|
cbq(19:30)=pp*s8(5)
|
||
|
|
cbq(31:42)=pp*s8(7)
|
||
|
|
cbi(1:12)=pp*s8(2)
|
||
|
|
cbi(13:24)=pp*s8(4)
|
||
|
|
cbi(25:36)=pp*s8(6)
|
||
|
|
cbi(37:42)=pp(1:6)*s8(8)
|
||
|
|
cb=cmplx(cbi,cbq)
|
||
|
|
|
||
|
|
first=.false.
|
||
|
|
endif
|
||
|
|
|
||
|
|
navg=sum(iavmask)
|
||
|
|
xmax=0.0
|
||
|
|
bestf=0.0
|
||
|
|
do ifr=-ntol,ntol,ndf !Find freq that maximizes sync
|
||
|
|
ferr=ifr
|
||
|
|
call tweak1(cdat,n,-(1500+ferr),cdat2)
|
||
|
|
c=0
|
||
|
|
do i=1,8
|
||
|
|
ib=(i-1)*NSPM+1
|
||
|
|
ie=ib+NSPM-1
|
||
|
|
if( iavmask(i) .eq. 1 ) then
|
||
|
|
c(1:NSPM)=c(1:NSPM)+cdat2(ib:ie)
|
||
|
|
endif
|
||
|
|
enddo
|
||
|
|
|
||
|
|
cc=0
|
||
|
|
ct2(1:NSPM)=c
|
||
|
|
ct2(NSPM+1:2*NSPM)=c
|
||
|
|
do ish=0,NSPM-1
|
||
|
|
cc(ish)=dot_product(ct2(1+ish:42+ish)+ct2(336+ish:377+ish),cb(1:42))
|
||
|
|
enddo
|
||
|
|
|
||
|
|
xcc=abs(cc)
|
||
|
|
xb=maxval(xcc)/(48.0*sqrt(float(navg)))
|
||
|
|
if(xb.gt.xmax) then
|
||
|
|
xmax=xb
|
||
|
|
bestf=ferr
|
||
|
|
cs=c
|
||
|
|
xccs=xcc
|
||
|
|
endif
|
||
|
|
enddo
|
||
|
|
|
||
|
|
fest=1500+bestf
|
||
|
|
c=cs
|
||
|
|
xcc=xccs
|
||
|
|
|
||
|
|
! Find npeaks largest peaks
|
||
|
|
do ipk=1,npeaks
|
||
|
|
iloc=maxloc(xcc)
|
||
|
|
ic2=iloc(1)
|
||
|
|
ipklocs(ipk)=ic2
|
||
|
|
pkamps(ipk)=xcc(ic2-1)
|
||
|
|
xcc(max(0,ic2-7):min(NSPM-1,ic2+7))=0.0
|
||
|
|
enddo
|
||
|
|
|
||
|
|
!write(*,*) xmax,bestf,fest,pkamps(1)/(48.0*sqrt(float(navg))),ipklocs(1),ipklocs(2)
|
||
|
|
snr=-6.0
|
||
|
|
return
|
||
|
|
end subroutine msk144sync
|