WSJT-X/lib/msk144_decode.f90

63 lines
1.7 KiB
Fortran
Raw Normal View History

subroutine msk144_decode(id2,npts,nutc,nprint,mycall,hiscall, &
bShMsgs,ntol,t0,line)
! Calls the experimental decoder for MSK 72ms/16ms messages
use timer_module, only: timer
parameter (NMAX=30*12000)
parameter (NFFTMAX=512*1024)
integer*2 id2(0:NMAX) !Raw i*2 data, up to T/R = 30 s
integer hist(0:32868)
real d(0:NMAX) !Raw r*4 data
complex c(NFFTMAX) !Complex (analytic) data
character*80 line(100) !Decodes passed back to caller
character*6 mycall,hiscall
logical*1 bShMsgs
line(1:100)(1:1)=char(0)
if(maxval(id2(1:npts)).eq.0 .and. minval(id2(1:npts)).eq.0) go to 900
if( npts .lt. 0.25*12000 ) go to 900 !Min record length 0.25s.
hist=0
do i=0,npts-1
n=abs(id2(i))
hist(n)=hist(n)+1
enddo
ns=0
do n=0,32768
ns=ns+hist(n)
if(ns.gt.npts/2) exit
enddo
fac=1.0/(1.5*n)
d(0:npts-1)=fac*id2(0:npts-1)
n=log(float(npts))/log(2.0) + 1.0
nfft=min(2**n,1024*1024)
call timer('analytic',0)
call analytic(d,npts,nfft,c) !Convert to analytic signal and filter
call timer('analytic',1)
call timer('detec144',0)
call detectmsk144(c,npts,line,nline,nutc,ntol,t0)
call timer('detec144',1)
if( nprint .ne. 0 ) then
do i=1,nline
write(*,'(a80)') line(i)
enddo
endif
if(nline.eq.0 .and. bShMsgs) then
call timer('detect40',0)
call detectmsk40(c,npts,mycall,hiscall,line,nline,nutc,ntol,t0)
call timer('detect40',1)
if( nprint .ne. 0 ) then
do i=1,nline
write(*,'(a80)') line(i)
enddo
endif
endif
if(line(1)(1:6).eq.' ') line(1)(1:1)=char(0)
900 return
end subroutine msk144_decode