WSJT-X/lib/jt4_decode.f90

412 lines
12 KiB
Fortran
Raw Normal View History

module jt4_decode
type :: jt4_decoder
procedure(jt4_decode_callback), pointer :: decode_callback => null ()
procedure(jt4_average_callback), pointer :: average_callback => null ()
contains
procedure :: decode
procedure, private :: wsjt4, avg4
end type jt4_decoder
! Callback function to be called with each decode
abstract interface
subroutine jt4_decode_callback (this, snr, dt, freq, have_sync, &
sync, is_deep, decoded, qual, ich, is_average, ave)
import jt4_decoder
implicit none
class(jt4_decoder), intent(inout) :: this
integer, intent(in) :: snr
real, intent(in) :: dt
integer, intent(in) :: freq
logical, intent(in) :: have_sync
logical, intent(in) :: is_deep
character(len=1), intent(in) :: sync
character(len=22), intent(in) :: decoded
real, intent(in) :: qual
integer, intent(in) :: ich
logical, intent(in) :: is_average
integer, intent(in) :: ave
end subroutine jt4_decode_callback
end interface
! Callback function to be called with each average result
abstract interface
subroutine jt4_average_callback (this, used, utc, sync, dt, freq, flip)
import jt4_decoder
implicit none
class(jt4_decoder), intent(inout) :: this
logical, intent(in) :: used
integer, intent(in) :: utc
real, intent(in) :: sync
real, intent(in) :: dt
integer, intent(in) :: freq
logical, intent(in) :: flip
end subroutine jt4_average_callback
end interface
contains
subroutine decode(this,decode_callback,dd,jz,nutc,nfqso,ntol0,emedelay, &
dttol,nagain,ndepth,nclearave,minsync,minw,nsubmode,mycall,hiscall, &
hisgrid,nlist0,listutc0,average_callback)
use jt4
use timer_module, only: timer
class(jt4_decoder), intent(inout) :: this
procedure(jt4_decode_callback) :: decode_callback
integer, intent(in) :: jz,nutc,nfqso,ntol0,ndepth,minsync,minw,nsubmode, &
nlist0,listutc0(10)
real, intent(in) :: dd(jz),emedelay,dttol
logical, intent(in) :: nagain, nclearave
character(len=12), intent(in) :: mycall,hiscall
character(len=6), intent(in) :: hisgrid
procedure(jt4_average_callback), optional :: average_callback
real*4 dat(30*11025)
character*6 cfile6
this%decode_callback => decode_callback
if (present (average_callback)) then
this%average_callback => average_callback
end if
mode4=nch(nsubmode+1)
ntol=ntol0
neme=0
lumsg=6 !### temp ? ###
ndiag=1
nlist=nlist0
listutc=listutc0
! Lowpass filter and decimate by 2
call timer('lpf1 ',0)
call lpf1(dd,jz,dat,jz2)
call timer('lpf1 ',1)
write(cfile6(1:4),1000) nutc
1000 format(i4.4)
cfile6(5:6)=' '
call timer('wsjt4 ',0)
call this%wsjt4(dat,jz2,nutc,NClearAve,minsync,ntol,emedelay,dttol,mode4, &
minw,mycall,hiscall,hisgrid,nfqso,NAgain,ndepth,neme)
call timer('wsjt4 ',1)
return
end subroutine decode
subroutine wsjt4(this,dat,npts,nutc,NClearAve,minsync,ntol,emedelay,dttol, &
mode4,minw,mycall,hiscall,hisgrid,nfqso,NAgain,ndepth,neme)
! Orchestrates the process of decoding JT4 messages. Note that JT4
! always operates as if in "Single Decode" mode; it looks for only one
! decodable signal in the FTol range.
use jt4
use timer_module, only: timer
class(jt4_decoder), intent(inout) :: this
integer, intent(in) :: npts,nutc,minsync,ntol,mode4,minw, &
nfqso,ndepth,neme
logical, intent(in) :: NAgain,NClearAve
character(len=12), intent(in) :: mycall,hiscall
character(len=6), intent(in) :: hisgrid
real, intent(in) :: dat(npts) !Raw data
logical first,prtavg
character decoded*22,special*5
character*22 avemsg,deepmsg,deepave,blank,deepmsg0,deepave1
character csync*1
data first/.true./,nutc0/-999/,nfreq0/-999999/
save
if(first) then
nsave=0
first=.false.
blank=' '
! Silence compiler warnings
if(dttol.eq.-99.0 .and. emedelay.eq.-99.0 .and. nagain) stop
endif
zz=0.
! syncmin=3.0 + minsync
syncmin=1.0+minsync
naggressive=0
if(ndepth.ge.2) naggressive=1
nq1=3
nq2=6
if(naggressive.eq.1) nq1=1
if(NClearAve) then
nsave=0
iutc=-1
nfsave=0.
listutc=0
ppsave=0.
rsymbol=0.
dtsave=0.
syncsave=0.
nfanoave=0
ndeepave=0
endif
! Attempt to synchronize: look for sync pattern, get DF and DT.
call timer('sync4 ',0)
call sync4(dat,npts,ntol,nfqso,4,mode4,minw+1,dtx,dfx, &
snrx,snrsync,flip,width)
sync=snrsync
dtxz=dtx-0.8
nfreqz=nint(dfx)
call timer('sync4 ',1)
nsnr=-26
if(sync.lt.syncmin) then
if (associated (this%decode_callback)) then
call this%decode_callback(nsnr,dtxz,nfreqz,.false.,csync, &
.false.,decoded,0.,ich,.false.,0)
end if
go to 990
endif
! We have achieved sync
nsnr=nint(snrsync - 22.9)
decoded=blank
deepmsg=blank
special=' '
nsync=sync
nsnrlim=-33
csync='*'
if(flip.lt.0.0) csync='#'
qbest=0.
qabest=0.
prtavg=.false.
do idt=-2,2
dtx=dtxz + 0.03*idt
nfreq=nfreqz + 2*idf
! Attempt a single-sequence decode, including deep4 if Fano fails.
call timer('decode4 ',0)
call decode4(dat,npts,dtx,nfreq,flip,mode4,ndepth,neme,minw, &
mycall,hiscall,hisgrid,decoded,nfano,deepmsg,qual,ich)
call timer('decode4 ',1)
if(nfano.gt.0) then
! Fano succeeded: report the message and return !Fano OK
if (associated (this%decode_callback)) then
call this%decode_callback(nsnr,dtx,nfreq,.true.,csync, &
.false.,decoded,99.,ich,.false.,0)
end if
nsave=0
go to 990
else !Fano failed
if(qual.gt.qbest) then
dtx0=dtx
nfreq0=nfreq
deepmsg0=deepmsg
ich0=ich
qbest=qual
endif
endif
if(idt.ne.0) cycle
! Single-sequence Fano decode failed, so try for an average Fano decode:
qave=0.
! If we're doing averaging, call avg4
if(iand(ndepth,16).eq.16 .and. (.not.prtavg)) then
if(nutc.ne.nutc0 .or. abs(nfreq-nfreq0).gt.ntol) then
! This is a new minute or a new frequency, so call avg4.
nutc0=nutc !Try decoding average
nfreq0=nfreq
nsave=nsave+1
nsave=mod(nsave-1,64)+1
call timer('avg4 ',0)
call this%avg4(nutc,sync,dtx,flip,nfreq,mode4,ntol,ndepth,neme, &
mycall,hiscall,hisgrid,nfanoave,avemsg,qave,deepave,ich, &
ndeepave)
call timer('avg4 ',1)
endif
if(nfanoave.gt.0) then
! Fano succeeded: report the message AVG FANO OK
if (associated (this%decode_callback)) then
call this%decode_callback(nsnr,dtx,nfreq,.true.,csync, &
.false.,avemsg,99.,ich,.true.,nfanoave)
end if
prtavg=.true.
cycle
else
if(qave.gt.qabest) then
dtx1=dtx
nfreq1=nfreq
deepave1=deepave
ich1=ich
qabest=qave
endif
endif
endif
enddo
dtx=dtx0
nfreq=nfreq0
deepmsg=deepmsg0
ich=ich0
qual=qbest
if (associated (this%decode_callback)) then
if(int(qual).ge.nq1) then
call this%decode_callback(nsnr,dtx,nfreqz,.true.,csync,.true., &
deepmsg,qual,ich,.false.,0)
else
call this%decode_callback(nsnr,dtxz,nfreqz,.true.,csync, &
.false.,blank,0.,ich,.false.,0)
endif
end if
dtx=dtx1
nfreq=nfreq1
deepave=deepave1
ich=ich1
qave=qabest
if (associated (this%decode_callback) .and. ndeepave.ge.2) then
if(int(qave).ge.nq1) then
call this%decode_callback(nsnr,dtx,nfreq,.true.,csync,.true., &
deepave,qave,ich,.true.,ndeepave)
endif
end if
990 return
end subroutine wsjt4
subroutine avg4(this,nutc,snrsync,dtxx,flip,nfreq,mode4,ntol,ndepth,neme, &
mycall,hiscall,hisgrid,nfanoave,avemsg,qave,deepave,ichbest,ndeepave)
! Decodes averaged JT4 data
use jt4
class(jt4_decoder), intent(inout) :: this
character*22 avemsg,deepave,deepbest
character mycall*12,hiscall*12,hisgrid*6
character*1 csync,cused(64)
real sym(207,7)
integer iused(64)
logical first
data first/.true./
save
if(first) then
iutc=-1
nfsave=0
dtdiff=0.2
first=.false.
endif
do i=1,64
if(nutc.eq.iutc(i) .and. abs(nfreq-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
flipsave(nsave)=flip
ppsave(1:207,1:7,nsave)=rsymbol(1:207,1:7)
10 sym=0.
syncsum=0.
dtsum=0.
nfsum=0
nsum=0
do i=1,64
cused(i)='.'
if(iutc(i).lt.0) cycle
if(mod(iutc(i),2).ne.mod(nutc,2)) cycle !Use only same sequence
if(abs(dtxx-dtsave(i)).gt.dtdiff) cycle !DT must match
if(abs(nfreq-nfsave(i)).gt.ntol) cycle !Freq must match
if(flip.ne.flipsave(i)) cycle !Sync (*/#) must match
sym(1:207,1:7)=sym(1:207,1:7) + ppsave(1:207,1:7,i)
syncsum=syncsum + syncsave(i)
dtsum=dtsum + dtsave(i)
nfsum=nfsum + nfsave(i)
cused(i)='$'
nsum=nsum+1
iused(nsum)=i
enddo
if(nsum.lt.64) iused(nsum+1)=0
syncave=0.
dtave=0.
fave=0.
if(nsum.gt.0) then
sym=sym/nsum
syncave=syncsum/nsum
dtave=dtsum/nsum
fave=float(nfsum)/nsum
endif
do i=1,nsave
csync='*'
if(flipsave(i).lt.0.0) csync='#'
if (associated (this%average_callback)) then
call this%average_callback(cused(i) .eq. '$',iutc(i), &
syncsave(i),dtsave(i),nfsave(i),flipsave(i).lt.0.)
end if
enddo
sqt=0.
sqf=0.
do j=1,64
i=iused(j)
if(i.eq.0) exit
csync='*'
if(flipsave(i).lt.0.0) csync='#'
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
kbest=ich1
do k=ich1,ich2
call extract4(sym(1,k),ncount,avemsg) !Do the Fano decode
nfanoave=0
if(ncount.ge.0) then
ichbest=k
nfanoave=nsum
go to 900
endif
if(nch(k).ge.mode4) exit
enddo
deepave=' '
qave=0.
! Possibly should pass nadd=nused, also ?
if(iand(ndepth,32).eq.32) then
flipx=1.0 !Normal flip not relevant for ave msg
qbest=0.
do k=ich1,ich2
call deep4(sym(2,k),neme,flipx,mycall,hiscall,hisgrid,deepave,qave)
if(qave.gt.qbest) then
qbest=qave
deepbest=deepave
kbest=k
ndeepave=nsum
endif
if(nch(k).ge.mode4) exit
enddo
deepave=deepbest
qave=qbest
ichbest=kbest
endif
900 return
end subroutine avg4
end module jt4_decode