WSJT-X/lib/qra/q65/q65.f90
2021-01-10 16:30:07 -05:00

197 lines
5.3 KiB
Fortran

module q65
parameter (MAXAVE=64)
parameter (PLOG_MIN=-240.0) !List decoding threshold
integer nsave,nlist,LL0
integer iutc(MAXAVE)
integer iseq(MAXAVE)
integer listutc(10)
integer apsym0(58),aph10(10)
integer apmask(13),apsymbols(13)
integer navg,ibwa,ibwb
real f0save(MAXAVE)
real xdtsave(MAXAVE)
real snr1save(MAXAVE)
real,allocatable :: s3save(:,:,:)
real,allocatable :: s3avg(:,:)
contains
subroutine q65_avg(nutc,ntrperiod,LL,nfqso,ntol,lclearave,xdt,f0,snr1,s3)
! Accumulate Q65 spectra s3(LL,63) and associated parameters for
! message averaging.
character*6 cutc
real s3(-64:LL-65,63) !Symbol spectra
logical first,lclearave
data first/.true./
save
if(LL.ne.LL0) then
LL0=LL
if(allocated(s3save)) deallocate(s3save)
if(allocated(s3avg)) deallocate(s3avg)
allocate(s3save(-64:LL-65,63,MAXAVE))
allocate(s3avg(-64:LL-65,63))
s3save=0.
s3avg=0.
endif
if(first .or. lclearave) then
iutc=-1
iseq=-1
f0save=0.0
nsave=0
first=.false.
s3save=0.
s3avg=0.
endif
do i=1,MAXAVE !Don't save info more than once for same UTC and freq
if(nutc.eq.iutc(i) .and. abs(nfqso-f0save(i)).le.ntol) go to 900
enddo
! Save data for message averaging
nsave=nsave+1
if(nsave.gt.MAXAVE) nsave=nsave-MAXAVE
n=nutc
if(ntrperiod.ge.60) n=100*n
write(cutc,'(i6.6)') n
read(cutc,'(3i2)') ih,im,is
nsec=3600*ih + 60*im + is
iseq(nsave)=mod(nsec/ntrperiod,2) !T/R sequence: 0 (even) or 1 (odd)
iutc(nsave)=nutc !UTC, hhmm or hhmmss
snr1save(nsave)=snr1 !SNR from sync
xdtsave(nsave)=xdt !DT
f0save(nsave)=f0 !f0
s3save(:,:,nsave)=s3(:,:) !Symbol spectra
900 return
end subroutine q65_avg
subroutine q65_avg2(ntrperiod,baud,nsubmode,nQSOprogress,lapcqonly, &
codewords,ncw,xdt,f0,snr2,dat4,idec)
use packjt77
use timer_module, only: timer
character*78 c78
character*1 cused(MAXAVE)
character*37 avemsg
integer dat4(13)
integer codewords(63,206)
integer apmask1(78),apsymbols1(78)
logical lapcqonly
mode_q65=2**nsubmode
dtdiff=0.038
if(ntrperiod.eq.30) then
dtdiff=0.08
else if(ntrperiod.eq.60) then
dtdiff=0.16
else if(ntrperiod.eq.120) then
dtdiff=0.4
else if(ntrperiod.eq.300) then
dtdiff=0.9
endif
dtdiff=3.5*dtdiff
f0diff=2.5*baud*mode_q65
navg=0
s3avg=0.
! Find previously saved spectra that should be averaged with this one
do i=1,MAXAVE
cused(i)='.' !Flag for "not used"
if(iutc(i).lt.0) cycle
if(iseq(i).ne.iseq(nsave)) cycle !Sequence must match
if(abs(xdt-xdtsave(i)).gt.dtdiff) cycle !DT must be close
if(abs(f0-f0save(i)).gt.f0diff) cycle !Freq must match
cused(i)='$' !Flag for "use this one"
s3avg=s3avg + s3save(:,:,i) !Add this spectrum
navg=navg+1
enddo
! Write parameters for display to User in the Message Averaging (F7) window.
do i=1,MAXAVE
if(iutc(i).lt.0) cycle
if(ntrperiod.le.30) write(14,1000) cused(i),iutc(i),snr1save(i), &
xdtsave(i),f0save(i)
1000 format(a1,i7.6,f6.1,f6.2,f7.1)
if(ntrperiod.ge.60) write(14,1001) cused(i),iutc(i),snr1save(i), &
xdtsave(i),f0save(i)
1001 format(a1,i5.4,f6.1,f6.2,f7.1)
enddo
if(navg.lt.2) go to 100
s3avg=s3avg/navg
do ibw=ibwa,ibwb
b90=1.72**ibw
b90ts=b90/baud
call timer('dec1avg ',0)
call q65_dec1(s3avg,nsubmode,b90ts,codewords,ncw,esnodb,irc,dat4,avemsg)
call timer('dec1avg ',1)
if(irc.ge.0) then
snr2=esnodb - 0.5*db(2500.0/baud) + 3.0 !Empirical adjustment
snr2=snr2 - db(float(navg)) !Is this right?
idec=100+navg
go to 100
endif
enddo
! Loop over full range of available AP
! APmask=0
! APsymbols=0
npasses=2
if(nQSOprogress.eq.5) npasses=3
if(lapcqonly) npasses=1
iaptype=0
ncontest=0 !### ??? ###
do ipass=0,npasses
apmask=0 !Try first with no AP information
apsymbols=0
if(ipass.ge.1) then
! Subsequent passes use AP information appropiate for nQSOprogress
call q65_ap(nQSOprogress,ipass,ncontest,lapcqonly,iaptype, &
apsym0,apmask1,apsymbols1)
write(c78,1050) apmask1
1050 format(78i1)
read(c78,1060) apmask
1060 format(13b6.6)
write(c78,1050) apsymbols1
read(c78,1060) apsymbols
endif
do ibw=ibwa,ibwb
b90=1.72**ibw
b90ts=b90/baud
call timer('dec2avg ',0)
call q65_dec2(s3avg,nsubmode,b90ts,esnodb,irc,dat4,avemsg)
call timer('dec2avg ',1)
if(irc.ge.0) then
snr2=esnodb - db(2500.0/baud) + 3.0 !Empirical adjustment
snr2=snr2 - 0.5*db(float(navg)) !Is this right?
idec=100*(iaptype+2) + navg
go to 100
endif
enddo ! ibw
enddo ! ipass
100 return
end subroutine q65_avg2
subroutine q65_clravg
iutc=-1
iseq=-1
snr1save=0.
xdtsave=0.
f0save=0.0
nsave=0
if(allocated(s3save)) s3save=0.
if(allocated(s3avg)) s3avg=0.
return
end subroutine q65_clravg
end module q65