WSJT-X/lib/jt65_decode.f90
Joe Taylor 1c948c1566 Further progress toward correct message averaging and hinted decoding
in JT65 mode.


git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@6522 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
2016-03-10 20:29:00 +00:00

396 lines
12 KiB
Fortran

module jt65_decode
integer, parameter :: NSZ=3413, NZMAX=60*12000, NFFT=1000
type :: jt65_decoder
procedure(jt65_decode_callback), pointer :: callback => null()
contains
procedure :: decode
end type jt65_decoder
!
! Callback function to be called with each decode
!
abstract interface
subroutine jt65_decode_callback(this,utc,sync,snr,dt,freq,drift, &
decoded,ft,qual,nsmo,nsum,minsync,nsubmode,naggressive)
import jt65_decoder
implicit none
class(jt65_decoder), intent(inout) :: this
integer, intent(in) :: utc
real, intent(in) :: sync
integer, intent(in) :: snr
real, intent(in) :: dt
integer, intent(in) :: freq
integer, intent(in) :: drift
character(len=22), intent(in) :: decoded
integer, intent(in) :: ft
integer, intent(in) :: qual
integer, intent(in) :: nsmo
integer, intent(in) :: nsum
integer, intent(in) :: minsync
integer, intent(in) :: nsubmode
integer, intent(in) :: naggressive
end subroutine jt65_decode_callback
end interface
contains
subroutine decode(this,callback,dd0,npts,newdat,nutc,nf1,nf2,nfqso, &
ntol,nsubmode,minsync,nagain,n2pass,nrobust,ntrials,naggressive, &
ndepth,nclearave,mycall,hiscall,hisgrid,nexp_decode)
! Process dd0() data to find and decode JT65 signals.
use jt65_mod
use timer_module, only: timer
include 'constants.f90'
class(jt65_decoder), intent(inout) :: this
procedure(jt65_decode_callback) :: callback
real, intent(in) :: dd0(NZMAX)
integer, intent(in) :: npts, nutc, nf1, nf2, nfqso, ntol &
, nsubmode, minsync, n2pass, ntrials, naggressive, ndepth &
, nexp_decode
logical, intent(in) :: newdat, nagain, nrobust
character(len=12), intent(in) :: mycall, hiscall
character(len=6), intent(in) :: hisgrid
real dd(NZMAX)
real ss(322,NSZ)
real savg(NSZ)
real a(5)
character*22 decoded,decoded0,avemsg,deepave
type candidate
real freq
real dt
real sync
end type candidate
type(candidate) ca(300)
type accepted_decode
real freq
real dt
real sync
character*22 decoded
end type accepted_decode
type(accepted_decode) dec(50)
logical :: first_time,robust,prtavg,single_decode
integer h0(0:11),d0(0:11)
real r0(0:11)
common/decstats/ntry65a,ntry65b,n65a,n65b,num9,numfano
common/steve/thresh0
! 0 1 2 3 4 5 6 7 8 9 10 11
data h0/41,42,43,43,44,45,46,47,48,48,49,49/
data d0/71,72,73,74,76,77,78,80,81,82,83,83/
! 0 1 2 3 4 5 6 7 8 9 10 11
data r0/0.70,0.72,0.74,0.76,0.78,0.80,0.82,0.84,0.86,0.88,0.90,0.90/
data nutc0/-999/,nfreq0/-999/,nsave/0/
save
this%callback => callback
first_time=newdat
robust=nrobust
dd=dd0
ndecoded=0
do ipass=1,n2pass ! 2-pass decoding loop
first_time=.true.
if(ipass.eq.1) then !first-pass parameters
thresh0=2.5
nsubtract=1
elseif( ipass.eq.2 ) then !second-pass parameters
thresh0=2.5
nsubtract=0
endif
if(n2pass.lt.2) nsubtract=0
! if(newdat) then
call timer('symsp65 ',0)
ss=0.
call symspec65(dd,npts,ss,nhsym,savg) !Get normalized symbol spectra
call timer('symsp65 ',1)
! endif
nfa=nf1
nfb=nf2
single_decode=iand(nexp_decode,32).ne.0
if(single_decode .or. (naggressive.gt.0 .and. ntol.lt.1000)) then
nfa=max(200,nfqso-ntol)
nfb=min(4000,nfqso+ntol)
thresh0=1.0
endif
! robust = .false.: use float ccf. Only if ncand>50 fall back to robust (1-bit) ccf
! robust = .true. : use only robust (1-bit) ccf
ncand=0
if(.not.robust) then
call timer('sync65 ',0)
call sync65(ss,nfa,nfb,naggressive,ntol,nhsym,ca,ncand,0)
call timer('sync65 ',1)
endif
if(ncand.gt.50) robust=.true.
if(robust) then
ncand=0
call timer('sync65 ',0)
call sync65(ss,nfa,nfb,naggressive,ntol,nhsym,ca,ncand,1)
call timer('sync65 ',1)
endif
! If a candidate was found within +/- ntol of nfqso, move it into ca(1).
call fqso_first(nfqso,ntol,ca,ncand)
if(single_decode) ncand=1
nvec=ntrials
if(ncand.gt.75) then
! write(*,*) 'Pass ',ipass,' ncandidates too large ',ncand
nvec=100
endif
df=12000.0/NFFT !df = 12000.0/8192 = 1.465 Hz
mode65=2**nsubmode
nflip=1 !### temporary ###
nqd=0
decoded0=""
freq0=0.
prtavg=.false.
do icand=1,ncand
freq=ca(icand)%freq
dtx=ca(icand)%dt
sync1=ca(icand)%sync
if(ipass.eq.1) ntry65a=ntry65a + 1
if(ipass.eq.2) ntry65b=ntry65b + 1
call timer('decod65a',0)
call decode65a(dd,npts,first_time,nqd,freq,nflip,mode65,nvec, &
naggressive,ndepth,mycall,hiscall,hisgrid,nexp_decode, &
sync2,a,dtx,nft,qual,nhist,nsmo,decoded)
call timer('decod65a',1)
! ncandidates=param(0)
nhard_min=param(1)
! nsoft_min=param(2)
! nera_best=param(3)
nrtt1000=param(4)
ntotal_min=param(5)
! ntry=param(6)
! nq1000=param(7)
! npp1=param(8)
nsmo=param(9)
nfreq=nint(freq+a(1))
ndrift=nint(2.0*a(2))
s2db=10.0*log10(sync2) - 35 !### empirical ###
nsnr=nint(s2db)
if(nsnr.lt.-30) nsnr=-30
if(nsnr.gt.-1) nsnr=-1
if(nft.ne.1 .and. ndepth.ge.4 .and. (.not.prtavg)) then
! Single-sequence FT decode failed, so try for an average FT decode.
if(nutc.ne.nutc0 .or. abs(nfreq-nfreq0).gt.ntol) then
! This is a new minute or a new frequency, so call avg65.
nutc0=nutc
nfreq0=nfreq
nsave=nsave+1
nsave=mod(nsave-1,64)+1
call avg65(nutc,nsave,sync1,dtx,nflip,nfreq,mode65,ntol, &
ndepth,ntrials,naggressive,nclearave,neme,mycall, &
hiscall,hisgrid,nftt,avemsg,qave,deepave,nsum,ndeepave)
if (associated(this%callback)) then
call this%callback(nutc,sync1,nsnr,dtx-1.0,nfreq,ndrift, &
avemsg,nftt,nqual,nsmo,nsum,minsync,nsubmode, &
naggressive)
prtavg=.true.
cycle
end if
endif
endif
if(nftt.eq.1) then
nft=1
decoded=avemsg
go to 5
endif
n=naggressive
rtt=0.001*nrtt1000
if(nft.lt.2) then
if(nhard_min.gt.50) cycle
if(nhard_min.gt.h0(n)) cycle
if(ntotal_min.gt.d0(n)) cycle
if(rtt.gt.r0(n)) cycle
endif
5 if(decoded.eq.decoded0 .and. abs(freq-freq0).lt. 3.0 .and. &
minsync.ge.0) cycle !Don't display dupes
if(decoded.ne.' ' .or. minsync.lt.0) then
if( nsubtract .eq. 1 ) then
call timer('subtr65 ',0)
call subtract65(dd,npts,freq,dtx)
call timer('subtr65 ',1)
endif
ndupe=0 ! de-dedupe
do i=1, ndecoded
if(decoded==dec(i)%decoded) then
ndupe=1
exit
endif
enddo
if(ndupe.ne.1 .or. minsync.lt.0) then
if(ipass.eq.1) n65a=n65a + 1
if(ipass.eq.2) n65b=n65b + 1
ndecoded=ndecoded+1
dec(ndecoded)%freq=freq+a(1)
dec(ndecoded)%dt=dtx
dec(ndecoded)%sync=sync2
dec(ndecoded)%decoded=decoded
nqual=min(qual,9999.0)
if (associated(this%callback)) then
call this%callback(nutc,sync1,nsnr,dtx-1.0,nfreq,ndrift, &
decoded,nft,nqual,nsmo,nsum,minsync,nsubmode, &
naggressive)
end if
endif
decoded0=decoded
freq0=freq
if(decoded0.eq.' ') decoded0='*'
endif
enddo !Candidate loop
if(ndecoded.lt.1) exit
enddo !Two-pass loop
return
end subroutine decode
subroutine avg65(nutc,nsave,snrsync,dtxx,nflip,nfreq,mode65,ntol,ndepth, &
ntrials,naggressive,nclearave,neme,mycall,hiscall,hisgrid,nftt, &
avemsg,qave,deepave,nsum,ndeepave)
! Decodes averaged JT65 data
use jt65_mod
parameter (MAXAVE=64)
character*22 avemsg,deepave,deepbest
character mycall*12,hiscall*12,hisgrid*6
character*1 csync,cused(64)
integer iused(64)
! Accumulated data for message averaging
integer iutc(MAXAVE)
integer nfsave(MAXAVE)
integer listutc(10)
integer nflipsave(MAXAVE)
real s1b(-255:256,126)
real s1save(-255:256,126,MAXAVE)
real s3save(64,63,MAXAVE)
real s3b(64,63)
real dtsave(MAXAVE)
real syncsave(MAXAVE)
logical first
data first/.true./
save
if(first .or. (nclearave.eq.1)) then
iutc=-1
nfsave=0
dtdiff=0.2
first=.false.
! s3a=0.
nsave=1 !### ???
endif
nclearave=0
do i=1,64
if(nutc.eq.iutc(i) .and. abs(nhz-nfsave(i)).le.ntol) go to 10
enddo
! Save data for message averaging
iutc(nsave)=nutc
syncsave(nsave)=snrsync
dtsave(nsave)=dtxx
nfsave(nsave)=nfreq
nflipsave(nsave)=nflip
s1save(-255:256,1:126,nsave)=s1
s3save(1:64,1:63,nsave)=s3a
10 syncsum=0.
dtsum=0.
nfsum=0
nsum=0
s3b=0.
do i=1,64 !Consider all saved spectra
cused(i)='.'
if(iutc(i).lt.0) cycle
if(mod(iutc(i),2).ne.mod(nutc,2)) cycle !Use only same (odd/even) seq
if(abs(dtxx-dtsave(i)).gt.dtdiff) cycle !DT must match
if(abs(nfreq-nfsave(i)).gt.ntol) cycle !Freq must match
if(nflip.ne.nflipsave(i)) cycle !Sync type (*/#) must match
s3b=s3b + s3save(1:64,1:63,i)
syncsum=syncsum + syncsave(i)
dtsum=dtsum + dtsave(i)
nfsum=nfsum + nfsave(i)
cused(i)='$'
nsum=nsum+1
iused(nsum)=i
enddo
if(nsum.lt.64) iused(nsum+1)=0
syncave=0.
dtave=0.
fave=0.
if(nsum.gt.0) then
syncave=syncsum/nsum
dtave=dtsum/nsum
fave=float(nfsum)/nsum
endif
do i=1,nsave
csync='*'
if(nflipsave(i).lt.0.0) csync='#'
write(14,1000) cused(i),iutc(i),syncsave(i),dtsave(i),nfsave(i),csync
1000 format(a1,i5.4,f6.1,f6.2,i6,1x,a1)
enddo
rewind 62
sqt=0.
sqf=0.
do j=1,64
i=iused(j)
if(i.eq.0) exit
csync='*'
if(nflipsave(i).lt.0) csync='#'
write(62,3001) i,iutc(i),syncsave(i),dtsave(i),nfsave(i),csync
3001 format(i3,i6.4,f6.1,f6.2,i6,1x,a1)
sqt=sqt + (dtsave(i)-dtave)**2
sqf=sqf + (nfsave(i)-fave)**2
enddo
rmst=0.
rmsf=0.
if(nsum.ge.2) then
rmst=sqrt(sqt/(nsum-1))
rmsf=sqrt(sqf/(nsum-1))
endif
write(62,3002)
3002 format(16x,'----- -----')
write(62,3003) dtave,nint(fave)
write(62,3003) rmst,nint(rmsf)
3003 format(15x,f6.2,i6)
flush(62)
nadd=nsum*mode65
nftt=0
! nexp_decode=0 !### not used, anyway
call extract(s3b,nadd,mode65,ntrials,naggressive,ndepth,mycall, &
hiscall,hisgrid,nexp_decode,ncount,nhist,avemsg,ltext,nftt,qual)
return
end subroutine avg65
end module jt65_decode