WSJT-X/lib/msk40sync.f90
Steven Franke 69d579388b First steps toward realtime short ping decoder for MSK40.
git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@7139 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
2016-10-02 01:43:31 +00:00

114 lines
2.7 KiB
Fortran

subroutine msk40sync(cdat,nframes,ntol,delf,navmask,npeaks,fc,fest, &
npklocs,nsuccess,c)
!$ use omp_lib
parameter (NSPM=240)
complex cdat(NSPM*nframes)
complex cdat2(NSPM*nframes,8)
complex c(NSPM) !Coherently averaged complex data
complex cs(NSPM,8)
complex cb(42) !Complex waveform for sync word
! integer*8 count0,count1,clkfreq
integer s8r(8)
integer iloc(1)
integer npklocs(npeaks)
integer navmask(nframes) ! defines which frames to average
real cbi(42),cbq(42)
real pkamps(npeaks)
real xcc(0:NSPM-1)
real xccs(0:NSPM-1,8)
real xm(8)
real bf(8)
real pp(12) !Half-sine pulse shape
logical first
data first/.true./
data s8r/0,1,0,0,1,1,1,0/
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
s8r=2*s8r-1
cbq(1:6)=pp(7:12)*s8r(1)
cbq(7:18)=pp*s8r(3)
cbq(19:30)=pp*s8r(5)
cbq(31:42)=pp*s8r(7)
cbi(1:12)=pp*s8r(2)
cbi(13:24)=pp*s8r(4)
cbi(25:36)=pp*s8r(6)
cbi(37:42)=pp(1:6)*s8r(8)
cb=cmplx(cbi,cbq)
first=.false.
endif
nfreqs=2*nint(ntol/delf) + 1
xm=0.0
bf=0.0
nthreads=1
!$ nthreads=min(8,int(OMP_GET_MAX_THREADS(),4))
nstep=nfreqs/nthreads
!$OMP PARALLEL NUM_THREADS(nthreads) PRIVATE(id,if1,if2)
id=1
!$ id=OMP_GET_THREAD_NUM() + 1 !Thread id = 1,2,...
if1=-nint(ntol/delf) + (id-1)*nstep
if2=if1+nstep-1
if(id.eq.nthreads) if2=nint(ntol/delf)
call msk40_freq_search(cdat,fc,if1,if2,delf,nframes,navmask,cb, &
cdat2(1,id),xm(id),bf(id),cs(1,id),xccs(1,id))
! write(73,3002) id,if1,if2,nfreqs,nthreads,bf(id),xm(id)
!3002 format(5i5,2f10.3)
!$OMP END PARALLEL
xmax=xm(1)
fest=fc+bf(1)
c=cs(1:NSPM,1)
xcc=xccs(0:NSPM-1,1)
if(nthreads.gt.1) then
do i=2,nthreads
if(xm(i).gt.xmax) then
xmax=xm(i)
fest=fc+bf(i)
c=cs(1:NSPM,i)
xcc=xccs(0:NSPM-1,i)
endif
enddo
endif
! Find npeaks largest peaks
do ipk=1,npeaks
iloc=maxloc(xcc)
ic2=iloc(1)
npklocs(ipk)=ic2
pkamps(ipk)=xcc(ic2-1)
xcc(max(0,ic2-7):min(NSPM-1,ic2+7))=0.0
enddo
if( xmax .lt. 0.7 ) then
nsuccess=0
else
nsuccess=1
endif
! call system_clock(count1,clkfreq)
! t=float(count1-count0)/clkfreq
! write(72,3001) nfreqs,OMP_GET_MAX_THREADS(),nthreads,t
!3001 format(3i6,f8.3)
return
end subroutine msk40sync