mirror of https://github.com/saitohirga/WSJT-X.git
Improvements to msk32 decoder.
git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@6947 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
This commit is contained in:
Steven Franke
parent
418f8b4ca6
commit
9d1498891a
|
|
@ -14,10 +14,7 @@ subroutine detectmsk32(cbig,n,mycall,partnercall,lines,nmessages,nutc,ntol,t00)
|
|||
complex cb(42) !Complex waveform for sync word
|
||||
complex cbr(42) !Complex waveform for reversed sync word
|
||||
complex cfac,cca,ccb
|
||||
complex cc(NPTS)
|
||||
complex ccr(NPTS)
|
||||
complex cc1(NPTS)
|
||||
complex cc2(NPTS)
|
||||
complex ccr1(NPTS)
|
||||
complex ccr2(NPTS)
|
||||
complex bb(6)
|
||||
|
|
@ -25,19 +22,17 @@ subroutine detectmsk32(cbig,n,mycall,partnercall,lines,nmessages,nutc,ntol,t00)
|
|||
integer, dimension(1) :: iloc
|
||||
integer icd(0:4095)
|
||||
integer ihammd(0:4096-1)
|
||||
integer nhashes(0:31)
|
||||
integer indices(MAXSTEPS)
|
||||
integer ipeaks(10)
|
||||
integer ig24(0:4096-1)
|
||||
integer ig(0:23,0:4095)
|
||||
integer isoftbits(32)
|
||||
integer likelymessages(0:31)
|
||||
logical qsocontext
|
||||
logical ismask(NFFT)
|
||||
real cbi(42),cbq(42)
|
||||
real detmet(-2:MAXSTEPS+3)
|
||||
real detfer(MAXSTEPS)
|
||||
real rcw(12)
|
||||
real dd(NPTS)
|
||||
real ddr(NPTS)
|
||||
real ferrs(MAXCAND)
|
||||
real pp(12) !Half-sine pulse shape
|
||||
|
|
@ -55,7 +50,7 @@ subroutine detectmsk32(cbig,n,mycall,partnercall,lines,nmessages,nutc,ntol,t00)
|
|||
'R-04','R-02','R+00','R+02','R+04','R+06','R+08','R+10','R+12', &
|
||||
'R+14','R+16','R+18','R+20','R+22','R+24', &
|
||||
'RRR ','73 '/
|
||||
save df,first,cb,cbr,fs,pi,twopi,dt,s8,rcw,pp,nmatchedfilter,ig24
|
||||
save df,first,cb,cbr,fs,nhashes,pi,twopi,dt,s8,rcw,pp,nmatchedfilter,ig24
|
||||
|
||||
if(first) then
|
||||
nmatchedfilter=1
|
||||
|
|
@ -103,22 +98,17 @@ subroutine detectmsk32(cbig,n,mycall,partnercall,lines,nmessages,nutc,ntol,t00)
|
|||
ig(j,i)=2*ib-1
|
||||
enddo
|
||||
enddo
|
||||
|
||||
|
||||
do i=0,31
|
||||
hashmsg=trim(mycall)//' '//trim(partnercall)//' '//rpt(i)
|
||||
call fmtmsg(hashmsg,iz)
|
||||
call hash(hashmsg,22,ihash)
|
||||
nhashes(i)=iand(ihash,127)
|
||||
enddo
|
||||
|
||||
first=.false.
|
||||
endif
|
||||
|
||||
! Define the 32 likely messages
|
||||
do irpt=0,31
|
||||
hashmsg=trim(mycall)//' '//trim(partnercall)//' '//rpt(irpt)
|
||||
call fmtmsg(hashmsg,iz)
|
||||
call hash(hashmsg,22,ihash)
|
||||
ihash=iand(ihash,127)
|
||||
igl=32*ihash + irpt
|
||||
likelymessages(irpt)=igl
|
||||
! write(*,*) irpt,hashmsg,igl,ig24(igl)
|
||||
enddo
|
||||
qsocontext=.false.
|
||||
|
||||
! Fill the detmet, detferr arrays
|
||||
nstepsize=48 ! 4ms steps
|
||||
nstep=(n-NPTS)/nstepsize
|
||||
|
|
@ -174,7 +164,6 @@ subroutine detectmsk32(cbig,n,mycall,partnercall,lines,nmessages,nutc,ntol,t00)
|
|||
enddo ! end of detection-metric and frequency error estimation loop
|
||||
|
||||
call indexx(detmet(1:nstep),nstep,indices) !find median of detection metric vector
|
||||
! xmed=detmet(indices(nstep/2))
|
||||
xmed=detmet(indices(nstep/4))
|
||||
detmet=detmet/xmed ! noise floor of detection metric is 1.0
|
||||
ndet=0
|
||||
|
|
@ -183,7 +172,7 @@ subroutine detectmsk32(cbig,n,mycall,partnercall,lines,nmessages,nutc,ntol,t00)
|
|||
!write(77,*) i,detmet(i),detfer(i)
|
||||
!enddo
|
||||
|
||||
do ip=1,MAXCAND ! use something like the "clean" algorithm to find candidates
|
||||
do ip=1,MAXCAND ! find candidates
|
||||
iloc=maxloc(detmet(1:nstep))
|
||||
il=iloc(1)
|
||||
if( (detmet(il) .lt. 4.2) ) exit
|
||||
|
|
@ -196,8 +185,12 @@ subroutine detectmsk32(cbig,n,mycall,partnercall,lines,nmessages,nutc,ntol,t00)
|
|||
detmet(max(1,il-3):min(nstep,il+3))=0.0
|
||||
! detmet(il)=0.0
|
||||
enddo
|
||||
|
||||
|
||||
! ndet=15
|
||||
! do ip=1,ndet
|
||||
! times(ip)=ip+0.012
|
||||
! snrs(ip)=-3.0
|
||||
! ferrs(ip)=0.0
|
||||
! write(*,*) ip,times(ip),snrs(ip),ferrs(ip)
|
||||
! enddo
|
||||
|
||||
|
|
@ -222,7 +215,7 @@ subroutine detectmsk32(cbig,n,mycall,partnercall,lines,nmessages,nutc,ntol,t00)
|
|||
if( nsnr .lt. -4 ) nsnr=-4
|
||||
if( nsnr .gt. 24 ) nsnr=24
|
||||
|
||||
! remove coarse freq error - should now be within a few Hz
|
||||
! remove coarse freq error
|
||||
call tweak1(cdat,NPTS,-(1500+ferr),cdat)
|
||||
|
||||
! attempt frame synchronization
|
||||
|
|
@ -291,7 +284,7 @@ subroutine detectmsk32(cbig,n,mycall,partnercall,lines,nmessages,nutc,ntol,t00)
|
|||
|
||||
! Final estimate of the carrier frequency - returned to the calling program
|
||||
fest=1500+ferr+ferr2
|
||||
|
||||
|
||||
do idf=0,6 ! frequency jitter
|
||||
if( idf .eq. 0 ) then
|
||||
deltaf=0.0
|
||||
|
|
@ -352,7 +345,7 @@ subroutine detectmsk32(cbig,n,mycall,partnercall,lines,nmessages,nutc,ntol,t00)
|
|||
enddo
|
||||
nbadsync1=(8-sum( (2*hardbits(1:8)-1)*s8r ) )/2
|
||||
nbadsync=nbadsync1
|
||||
if( nbadsync .gt. 3 ) cycle
|
||||
if( nbadsync .gt. 5 ) cycle
|
||||
|
||||
! normalize the softsymbols before submitting to decoder
|
||||
sav=sum(softbits)/32
|
||||
|
|
@ -361,66 +354,53 @@ subroutine detectmsk32(cbig,n,mycall,partnercall,lines,nmessages,nutc,ntol,t00)
|
|||
softbits=softbits/ssig
|
||||
isoftbits=softbits*1e4
|
||||
call timer('search32',0)
|
||||
if( qsocontext ) then ! search only 32 likely messages.
|
||||
icd=1e6
|
||||
ihammd=99
|
||||
do i=0,31
|
||||
ncw=ig24(likelymessages(i))
|
||||
icd(i)=0.0
|
||||
ihammd(i)=0
|
||||
do ii=1,24
|
||||
ib=iand(1,ishft(ncw,1-ii))
|
||||
ib=2*ib-1
|
||||
if( ib*softbits(ii+8) .lt. 0 ) then
|
||||
icd(i)=cd(i)+abs(softbits(ii+8))
|
||||
ihammd(i)=ihammd(i)+1
|
||||
endif
|
||||
enddo
|
||||
icd=1e6
|
||||
ihammd=99
|
||||
do i=0,4096-1
|
||||
icd(i)=0.0
|
||||
ihammd(i)=0
|
||||
do ii=1,24
|
||||
ib=ig(ii-1,i)
|
||||
if( ib*isoftbits(ii+8) .lt. 0 ) then
|
||||
icd(i)=icd(i)+abs(isoftbits(ii+8))
|
||||
ihammd(i)=ihammd(i)+1
|
||||
endif
|
||||
enddo
|
||||
else ! exhaustive decoder, look at every codeword.
|
||||
icd=1e6
|
||||
ihammd=99
|
||||
do i=0,4096-1
|
||||
! ncw=ig24(i)
|
||||
icd(i)=0.0
|
||||
ihammd(i)=0
|
||||
do ii=1,24
|
||||
! ib=iand(1,ishft(ncw,1-ii))
|
||||
ib=ig(ii-1,i)
|
||||
! ib=2*ib-1
|
||||
if( ib*isoftbits(ii+8) .lt. 0 ) then
|
||||
icd(i)=icd(i)+abs(isoftbits(ii+8))
|
||||
ihammd(i)=ihammd(i)+1
|
||||
endif
|
||||
enddo
|
||||
enddo
|
||||
endif
|
||||
enddo
|
||||
call timer('search32',1)
|
||||
icdm=minval(icd)
|
||||
iloc=minloc(icd)
|
||||
imsg=iloc(1)-1
|
||||
nrxrpt=iand(imsg,31)
|
||||
nrxhash=(imsg-nrxrpt)/32
|
||||
ihashflag=0
|
||||
if( nrxhash .eq. nhashes(nrxrpt) ) then
|
||||
ihashflag=1
|
||||
endif
|
||||
icd(imsg)=1e6
|
||||
icdm2=minval(icd)
|
||||
iloc=minloc(icd)
|
||||
imsg2=iloc(1)-1
|
||||
cdrat=icdm2/(icdm+1)
|
||||
cdrat2=icdm/(icdm2+1)
|
||||
if( (icdm .lt. icdbest) .or. ((icdm .eq. icdbest) .and. (ihammd(imsg) .lt. nhammdbest)) ) then
|
||||
cdratbest = cdrat
|
||||
cdrat2best = cdrat2
|
||||
icdbest = icdm
|
||||
imsgbest = imsg
|
||||
imsg2best = imsg2
|
||||
iavbest = iav
|
||||
ipbest = ip
|
||||
ipkbest = ipk
|
||||
idfbest = idf
|
||||
idbest = id
|
||||
iphabest = ipha
|
||||
nbadsyncbest = nbadsync
|
||||
nhammdbest = ihammd(imsg)
|
||||
if( ( nhammdbest .eq. 0 ) .and. (icdbest .eq. 0.0) .and. (cdratbest .gt. 2000.0) ) goto 999
|
||||
cdrat=real(icdm2)/(icdm+1)
|
||||
|
||||
if( ihashflag .eq. 1 ) then
|
||||
if( (icdm .lt. icdbest) .or. ((icdm .eq. icdbest) .and. (ihammd(imsg) .lt. nhammdbest)) ) then
|
||||
cdratbest = cdrat
|
||||
icdbest = icdm
|
||||
imsgbest = imsg
|
||||
imsg2best = imsg2
|
||||
iavbest = iav
|
||||
ipbest = ip
|
||||
ipkbest = ipk
|
||||
idfbest = idf
|
||||
idbest = id
|
||||
iphabest = ipha
|
||||
nbadsyncbest = nbadsync
|
||||
nhammdbest = ihammd(imsg)
|
||||
if( nhammdbest .eq. 0 ) goto 999
|
||||
endif
|
||||
endif
|
||||
|
||||
enddo ! phase loop
|
||||
enddo ! frame averaging loop
|
||||
enddo ! frequency dithering loop
|
||||
|
|
@ -430,44 +410,22 @@ subroutine detectmsk32(cbig,n,mycall,partnercall,lines,nmessages,nutc,ntol,t00)
|
|||
999 continue
|
||||
msgreceived=' '
|
||||
if( imsgbest .gt. 0 ) then
|
||||
if( ( nhammdbest+nbadsyncbest .le. 4 ) .and. cdratbest .gt. 5.0 ) then
|
||||
if( qsocontext ) then
|
||||
nrxrpt=iand(likelymessages(imsgbest),31)
|
||||
nrxhash=(likelymessages(imsgbest)-nrxrpt)/32
|
||||
imessage=likelymessages(imsgbest)
|
||||
else
|
||||
nrxrpt=iand(imsgbest,31)
|
||||
nrxhash=(imsgbest-nrxrpt)/32
|
||||
imessage=imsgbest
|
||||
endif
|
||||
|
||||
! See if this message has a hash that is expected for a message sent to mycall by partnercall
|
||||
hashmsg=trim(mycall)//' '//trim(partnercall)//' '//rpt(nrxrpt)
|
||||
call fmtmsg(hashmsg,iz)
|
||||
call hash(hashmsg,22,ihash)
|
||||
ihash=iand(ihash,127)
|
||||
|
||||
if(nrxhash.eq.ihash .or. t00.gt.0.0) then
|
||||
if(nrxhash.eq.ihash) then
|
||||
if( (icdbest .lt. 5000) .and. ( nhammdbest .le. 4 ) .and. &
|
||||
(nhammdbest+nbadsyncbest .lt. 5) .and. (cdratbest .gt. 3.5) ) then
|
||||
nrxrpt=iand(imsgbest,31)
|
||||
nrxhash=(imsgbest-nrxrpt)/32
|
||||
nmessages=1
|
||||
write(msgreceived,'(a1,a,1x,a,a1,1x,a4)') "<",trim(mycall), &
|
||||
trim(partnercall),">",rpt(nrxrpt)
|
||||
write(lines(nmessages),1020) nutc,nsnr,t0,nint(fest),msgreceived
|
||||
1020 format(i6.6,i4,f5.1,i5,' & ',a22)
|
||||
endif
|
||||
if(nrxhash.ne.ihash .and. t00.gt.0.0 .and. nsnr.gt.-4) then
|
||||
nmessages=1
|
||||
! write(msgreceived,'(a5,1x,a4)') "<...>",rpt(nrxrpt)
|
||||
write(msgreceived,'(a1,i3,1x,i3,a1,a4)') "<",nrxhash,ihash,">",rpt(nrxrpt)
|
||||
write(lines(nmessages),1020) nutc,nsnr,t0,nint(fest),msgreceived
|
||||
endif
|
||||
|
||||
! write(*,1022) nutc,ipbest,times(ipbest),snrs(ipbest),fest,nrxrpt,nrxhash, &
|
||||
! write(*,1022) nutc,ipbest,times(ipbest),snrs(ipbest),fest,nrxrpt,nrxhash,nhashes(nrxrpt), &
|
||||
! rpt(nrxrpt),imessage,ig24(imessage),nhammdbest, &
|
||||
! icdbest,cdratbest,cdrat2best,nbadsyncbest,ipkbest,idbest,idfbest,iavbest,iphabest
|
||||
!1022 format(i6.6,2x,i4,f8.3,f8.2,f8.2,i6,i6,a6,i8,i10,i4,i8,f10.2,f10.2,i5,i5,i5,i5,i5,i5)
|
||||
endif
|
||||
! icdbest,cdratbest,nbadsyncbest,ipkbest,idbest,idfbest,iavbest,iphabest
|
||||
!1022 format(i6.6,2x,i4,f8.3,f8.2,f8.2,i6,i6,i6,a6,i8,i10,i4,i8,f10.2,i5,i5,i5,i5,i5,i5)
|
||||
endif
|
||||
endif
|
||||
|
||||
return
|
||||
end subroutine detectmsk32
|
||||
|
|
|
|||
Loading…
Reference in New Issue