mirror of
https://github.com/saitohirga/WSJT-X.git
synced 2024-11-15 08:31:57 -05:00
454 lines
12 KiB
Fortran
454 lines
12 KiB
Fortran
module q65
|
|
|
|
parameter (NSTEP=8) !Time bins per symbol, in s1() and s1a()
|
|
parameter (PLOG_MIN=-240.0) !List decoding threshold
|
|
integer nsave,nlist,LL0
|
|
integer listutc(10)
|
|
integer apsym0(58),aph10(10)
|
|
integer apmask(13),apsymbols(13)
|
|
integer,dimension(22) :: isync = (/1,9,12,13,15,22,23,26,27,33,35, &
|
|
38,46,50,55,60,62,66,69,74,76,85/)
|
|
integer codewords(63,206)
|
|
integer navg,ibwa,ibwb,ncw,nsps,mode_q65,istep,nsmo,lag1,lag2
|
|
integer i0,j0
|
|
real,allocatable,save :: s1a(:,:) !Cumulative symbol spectra
|
|
real sync(85) !sync vector
|
|
real df,dtstep
|
|
|
|
contains
|
|
|
|
subroutine q65_dec0(iavg,nutc,iwave,ntrperiod,nfqso,ntol,ndepth,lclearave, &
|
|
emedelay,xdt,f0,snr1,width,dat4,snr2,idec)
|
|
|
|
! Top-level routine in q65 module
|
|
|
|
! Input: iavg 0 for single-period decode, 1 for average
|
|
! iwave(0:nmax-1) Raw data
|
|
! ntrperiod T/R sequence length (s)
|
|
! nfqso Target frequency (Hz)
|
|
! ntol Search range around nfqso (Hz)
|
|
! ndepth Requested decoding depth
|
|
! lclearave Flag to clear the accumulating array
|
|
! emedelay Extra delay for EME signals
|
|
! Output: xdt Time offset from nominal (s)
|
|
! f0 Frequency of sync tone
|
|
! snr1 Relative SNR of sync signal
|
|
! width Estimated Doppler spread
|
|
! dat4(13) Decoded message as 13 six-bit integers
|
|
! snr2 Estimated SNR of decoded signal
|
|
! idec Flag for decing results
|
|
! -1 No decode
|
|
! 0 No AP
|
|
! 1 "CQ ? ?"
|
|
! 2 "Mycall ? ?"
|
|
! 3 "MyCall HisCall ?"
|
|
|
|
use packjt77
|
|
use timer_module, only: timer
|
|
|
|
parameter (LN=2176*63) !LN=LL*NN; LL=64*(mode_q65+2), NN=63
|
|
integer*2 iwave(0:12000*ntrperiod-1) !Raw data
|
|
integer dat4(13)
|
|
character*37 decoded
|
|
logical first,lclearave
|
|
real, allocatable :: s1(:,:) !Symbol spectra, 1/8-symbol steps
|
|
real, allocatable :: s3(:,:) !Data-symbol energies s3(LL,63)
|
|
real, allocatable :: ccf(:,:) !CCF(freq,lag)
|
|
real, allocatable :: ccf1(:) !CCF(freq) at best lag
|
|
real, allocatable :: ccf2(:) !CCF(freq) at any lag
|
|
data first/.true./
|
|
save first
|
|
|
|
if(nutc+ndepth.eq.-999) stop !Silence compiler warnings
|
|
|
|
! Set some parameters and allocate storage for large arrays
|
|
irc=-2
|
|
idec=-1
|
|
snr1=0.
|
|
dat4=0
|
|
LL=64*(2+mode_q65)
|
|
nfft=nsps
|
|
df=12000.0/nfft !Freq resolution = baud
|
|
istep=nsps/NSTEP
|
|
iz=5000.0/df !Uppermost frequency bin, at 5000 Hz
|
|
txt=85.0*nsps/12000.0
|
|
jz=(txt+1.0)*12000.0/istep !Number of symbol/NSTEP bins
|
|
if(nsps.ge.6912) jz=(txt+2.0)*12000.0/istep !For TR 60 s and higher
|
|
ia=ntol/df
|
|
ia2=max(ia,10*mode_q65,nint(100.0/df))
|
|
nsmo=int(0.7*mode_q65*mode_q65)
|
|
if(nsmo.lt.1) nsmo=1
|
|
if(first) then !Generate the sync vector
|
|
sync=-22.0/63.0 !Sync tone OFF
|
|
do k=1,22
|
|
sync(isync(k))=1.0 !Sync tone ON
|
|
enddo
|
|
endif
|
|
|
|
allocate(s1(iz,jz))
|
|
allocate(s3(-64:LL-65,63))
|
|
allocate(ccf(-ia2:ia2,-53:214))
|
|
allocate(ccf1(-ia2:ia2))
|
|
allocate(ccf2(-ia2:ia2))
|
|
if(LL.ne.LL0 .or. lclearave) then
|
|
if(allocated(s1a)) deallocate(s1a)
|
|
allocate(s1a(iz,jz))
|
|
s1a=0.
|
|
navg=0
|
|
LL0=LL
|
|
endif
|
|
dtstep=nsps/(NSTEP*12000.0) !Step size in seconds
|
|
lag1=-1.0/dtstep
|
|
lag2=1.0/dtstep + 0.9999
|
|
if(nsps.ge.3600 .and. emedelay.gt.0) lag2=4.0/dtstep + 0.9999 !Include EME
|
|
j0=0.5/dtstep
|
|
if(nsps.ge.7200) j0=1.0/dtstep !Nominal start-signal index
|
|
|
|
s3=0.
|
|
if(iavg.eq.0) then
|
|
call timer('q65_syms',0)
|
|
! Compute symbol spectra with NSTEP time bins per symbol
|
|
call q65_symspec(iwave,ntrperiod*12000,iz,jz,s1)
|
|
call timer('q65_syms',1)
|
|
else
|
|
s1=s1a
|
|
endif
|
|
|
|
i0=nint(nfqso/df) !Target QSO frequency
|
|
if(i0-64.lt.1 .or. i0-65+LL.gt.iz) go to 900 !Frequency out of range
|
|
call pctile(s1(i0-64:i0-65+LL,1:jz),LL*jz,40,base)
|
|
s1=s1/base
|
|
|
|
! Apply fast AGC to the symbol spectra
|
|
s1max=20.0 !Empirical choice
|
|
do j=1,jz !### Maybe wrong way? ###
|
|
smax=maxval(s1(i0-64:i0-65+LL,j))
|
|
if(smax.gt.s1max) s1(i0-64:i0-65+LL,j)=s1(i0-64:i0-65+LL,j)*s1max/smax
|
|
enddo
|
|
|
|
dat4=0
|
|
if(ncw.gt.0) then
|
|
! Try list decoding via "Deep Likelihood".
|
|
call timer('ccf_85 ',0)
|
|
! Try to synchronize using all 85 symbols
|
|
call q65_ccf_85(s1,iz,jz,nfqso,ia,ia2,ipk,jpk,f0,xdt,imsg_best,ccf,ccf1)
|
|
call timer('ccf_85 ',1)
|
|
|
|
call timer('list_dec',0)
|
|
call q65_dec_q3(s1,iz,jz,s3,LL,ipk,jpk,snr2,dat4,idec,decoded)
|
|
call timer('list_dec',1)
|
|
if(idec.ne.0) then
|
|
ic=ia2/4;
|
|
base=(sum(ccf1(-ia2:-ia2+ic)) + sum(ccf1(ia2-ic:ia2)))/(2.0+2.0*ic);
|
|
ccf1=ccf1-base
|
|
smax=maxval(ccf1)
|
|
if(smax.gt.10.0) ccf1=10.0*ccf1/smax
|
|
base=(sum(ccf2(-ia2:-ia2+ic)) + sum(ccf2(ia2-ic:ia2)))/(2.0+2.0*ic);
|
|
ccf2=ccf2-base
|
|
smax=maxval(ccf2)
|
|
if(smax.gt.10.0) ccf2=10.0*ccf2/smax
|
|
endif
|
|
endif
|
|
|
|
! Get 2d CCF and ccf2 using sync symbols only
|
|
call q65_ccf_22(s1,iz,jz,nfqso,ia,ia2,ipk,jpk,f0,xdt,ccf,ccf2)
|
|
|
|
! Estimate rms on ccf baseline
|
|
sq=0.
|
|
nsq=0
|
|
jd=(lag2-lag1)/4
|
|
do i=-ia2,ia2
|
|
do j=lag1,lag2
|
|
if(abs(j-jpk).gt.jd .and. abs(i-ipk).gt.ia/2) then
|
|
sq=sq + ccf(i,j)**2
|
|
nsq=nsq+1
|
|
endif
|
|
enddo
|
|
enddo
|
|
rms=sqrt(sq/nsq)
|
|
smax=ccf(ipk,jpk)
|
|
snr1=smax/rms
|
|
ccf2=ccf2/rms
|
|
if(snr1.gt.10.0) ccf2=(10.0/snr1)*ccf2
|
|
|
|
if(idec.le.0) then
|
|
! The q3 decode attempt failed. Copy synchronied symbol spectra from s1
|
|
! into s3 and prepare to try a more general decode.
|
|
ccf1=ccf(:,jpk)/rms
|
|
if(snr1.gt.10.0) ccf1=(10.0/snr1)*ccf1
|
|
call q65_s1_to_s3(s1,iz,jz,ipk,jpk,LL,mode_q65,sync,s3)
|
|
endif
|
|
|
|
smax=maxval(ccf1)
|
|
i1=-9999
|
|
i2=-9999
|
|
do i=-ia,ia
|
|
if(i1.eq.-9999 .and. ccf1(i).ge.0.5*smax) i1=i
|
|
if(i2.eq.-9999 .and. ccf1(-i).ge.0.5*smax) i2=-i
|
|
enddo
|
|
width=df*(i2-i1)
|
|
|
|
! Write data for the red and orange sync curves.
|
|
do i=-ia2,ia2
|
|
freq=nfqso + i*df
|
|
write(17,1100) freq,ccf1(i),xdt,ccf2(i)
|
|
1100 format(4f10.3)
|
|
enddo
|
|
close(17)
|
|
|
|
900 return
|
|
end subroutine q65_dec0
|
|
|
|
subroutine q65_clravg
|
|
|
|
if(allocated(s1a)) s1a=0.
|
|
navg=0
|
|
|
|
return
|
|
end subroutine q65_clravg
|
|
|
|
subroutine q65_symspec(iwave,nmax,iz,jz,s1)
|
|
|
|
integer*2 iwave(0:nmax-1) !Raw data
|
|
real s1(iz,jz)
|
|
complex, allocatable :: c0(:) !Complex spectrum of symbol
|
|
|
|
allocate(c0(0:nsps-1))
|
|
nfft=nsps
|
|
fac=1/32767.0
|
|
do j=1,jz !Compute symbol spectra at step size
|
|
i1=(j-1)*istep
|
|
i2=i1+nsps-1
|
|
k=-1
|
|
do i=i1,i2,2 !Load iwave data into complex array c0, for r2c FFT
|
|
xx=iwave(i)
|
|
yy=iwave(i+1)
|
|
k=k+1
|
|
c0(k)=fac*cmplx(xx,yy)
|
|
enddo
|
|
c0(k+1:)=0.
|
|
call four2a(c0,nfft,1,-1,0) !r2c FFT
|
|
do i=1,iz
|
|
s1(i,j)=real(c0(i))**2 + aimag(c0(i))**2
|
|
enddo
|
|
! For large Doppler spreads, should we smooth the spectra here?
|
|
do i=1,nsmo
|
|
call smo121(s1(1:iz,j),iz)
|
|
enddo
|
|
enddo
|
|
s1a=s1a+s1
|
|
navg=navg+1
|
|
|
|
return
|
|
end subroutine q65_symspec
|
|
|
|
subroutine q65_dec_q3(s1,iz,jz,s3,LL,ipk,jpk,snr2,dat4,idec,decoded)
|
|
|
|
character*37 decoded
|
|
integer dat4(13)
|
|
real s1(iz,jz)
|
|
real s3(-64:LL-65,63)
|
|
|
|
i1=i0+ipk-64
|
|
i2=i1+LL-1
|
|
j=j0+jpk-7
|
|
n=0
|
|
do k=1,85
|
|
j=j+8
|
|
if(sync(k).gt.0.0) then
|
|
cycle
|
|
endif
|
|
n=n+1
|
|
if(j.ge.1 .and. j.le.jz) then
|
|
do i=0,LL-1
|
|
s3(i-64,n)=s1(i+i1,j) !Copy from s1 into s3
|
|
enddo
|
|
endif
|
|
enddo
|
|
|
|
nsubmode=0
|
|
if(mode_q65.eq.2) nsubmode=1
|
|
if(mode_q65.eq.4) nsubmode=2
|
|
if(mode_q65.eq.8) nsubmode=3
|
|
if(mode_q65.eq.16) nsubmode=4
|
|
baud=12000.0/nsps
|
|
|
|
do ibw=ibwa,ibwb
|
|
b90=1.72**ibw
|
|
b90ts=b90/baud
|
|
call q65_dec1(s3,nsubmode,b90ts,esnodb,irc,dat4,decoded)
|
|
if(irc.ge.0) then
|
|
snr2=esnodb - db(2500.0/baud) + 3.0 !Empirical adjustment
|
|
idec=3
|
|
exit
|
|
endif
|
|
enddo
|
|
|
|
return
|
|
end subroutine q65_dec_q3
|
|
|
|
subroutine q65_ccf_85(s1,iz,jz,nfqso,ia,ia2, &
|
|
ipk,jpk,f0,xdt,imsg_best,ccf,ccf1)
|
|
|
|
real s1(iz,jz)
|
|
real ccf(-ia2:ia2,-53:214)
|
|
real ccf1(-ia2:ia2)
|
|
integer ijpk(2)
|
|
integer itone(85)
|
|
|
|
ipk=0
|
|
jpk=0
|
|
ccf_best=0.
|
|
imsg_best=-1
|
|
do imsg=1,ncw
|
|
i=1
|
|
k=0
|
|
do j=1,85
|
|
if(j.eq.isync(i)) then
|
|
i=i+1
|
|
itone(j)=-1
|
|
else
|
|
k=k+1
|
|
itone(j)=codewords(k,imsg)
|
|
endif
|
|
enddo
|
|
! Compute 2D ccf using all 85 symbols in the list message
|
|
ccf=0.
|
|
iia=200.0/df
|
|
|
|
do lag=lag1,lag2
|
|
do k=1,85
|
|
j=j0 + NSTEP*(k-1) + 1 + lag
|
|
if(j.ge.1 .and. j.le.jz) then
|
|
do i=-ia2,ia2
|
|
ii=i0+mode_q65*itone(k)+i
|
|
if(ii.ge.iia .and. ii.le.iz) ccf(i,lag)=ccf(i,lag) + s1(ii,j)
|
|
enddo
|
|
endif
|
|
enddo
|
|
enddo
|
|
|
|
ccfmax=maxval(ccf(-ia:ia,:))
|
|
if(ccfmax.gt.ccf_best) then
|
|
ccf_best=ccfmax
|
|
ijpk=maxloc(ccf(-ia:ia,:))
|
|
ipk=ijpk(1)-ia-1
|
|
jpk=ijpk(2)-53-1
|
|
f0=nfqso + (ipk-mode_q65)*df
|
|
xdt=jpk*dtstep
|
|
imsg_best=imsg
|
|
ccf1=ccf(:,jpk)
|
|
endif
|
|
enddo ! imsg
|
|
|
|
return
|
|
end subroutine q65_ccf_85
|
|
|
|
subroutine q65_ccf_22(s1,iz,jz,nfqso,ia,ia2,ipk,jpk,f0,xdt,ccf,ccf2)
|
|
|
|
real s1(iz,jz)
|
|
real ccf(-ia2:ia2,-53:214)
|
|
real ccf2(-ia2:ia2)
|
|
integer ijpk(2)
|
|
|
|
ccf=0.
|
|
do lag=lag1,lag2
|
|
do k=1,85
|
|
n=NSTEP*(k-1) + 1
|
|
j=n+lag+j0
|
|
if(j.ge.1 .and. j.le.jz) then
|
|
do i=-ia2,ia2
|
|
if(i0+i.lt.1 .or. i0+i.gt.iz) cycle
|
|
ccf(i,lag)=ccf(i,lag) + sync(k)*s1(i0+i,j)
|
|
enddo
|
|
endif
|
|
enddo
|
|
enddo
|
|
do i=-ia2,ia2
|
|
ccf2(i)=maxval(ccf(i,:))
|
|
enddo
|
|
ijpk=maxloc(ccf(-ia:ia,:))
|
|
ipk=ijpk(1)-ia-1
|
|
jpk=ijpk(2)-53-1
|
|
f0=nfqso + ipk*df
|
|
xdt=jpk*dtstep
|
|
|
|
return
|
|
end subroutine q65_ccf_22
|
|
|
|
subroutine q65_dec1(s3,nsubmode,b90ts,esnodb,irc,dat4,decoded)
|
|
|
|
use packjt77
|
|
real s3(1,1) !Silence compiler warning that wants to see a 2D array
|
|
real s3prob(0:63,63) !Symbol-value probabilities
|
|
integer dat4(13)
|
|
character c77*77,decoded*37
|
|
logical unpk77_success
|
|
|
|
nFadingModel=1
|
|
decoded=' '
|
|
call q65_intrinsics_ff(s3,nsubmode,b90ts,nFadingModel,s3prob)
|
|
call q65_dec_fullaplist(s3,s3prob,codewords,ncw,esnodb,dat4,plog,irc)
|
|
if(sum(dat4).le.0) irc=-2
|
|
if(irc.ge.0 .and. plog.gt.PLOG_MIN) then
|
|
write(c77,1000) dat4(1:12),dat4(13)/2
|
|
1000 format(12b6.6,b5.5)
|
|
call unpack77(c77,0,decoded,unpk77_success) !Unpack to get msgsent
|
|
else
|
|
irc=-1
|
|
endif
|
|
|
|
return
|
|
end subroutine q65_dec1
|
|
|
|
subroutine q65_dec2(s3,nsubmode,b90ts,esnodb,irc,dat4,decoded)
|
|
|
|
use packjt77
|
|
real s3(1,1) !Silence compiler warning that wants to see a 2D array
|
|
real s3prob(0:63,63) !Symbol-value probabilities
|
|
integer dat4(13)
|
|
character c77*77,decoded*37
|
|
logical unpk77_success
|
|
|
|
nFadingModel=1
|
|
decoded=' '
|
|
call q65_intrinsics_ff(s3,nsubmode,b90ts,nFadingModel,s3prob)
|
|
call q65_dec(s3,s3prob,APmask,APsymbols,esnodb,dat4,irc)
|
|
if(sum(dat4).le.0) irc=-2
|
|
if(irc.ge.0) then
|
|
write(c77,1000) dat4(1:12),dat4(13)/2
|
|
1000 format(12b6.6,b5.5)
|
|
call unpack77(c77,0,decoded,unpk77_success) !Unpack to get msgsent
|
|
endif
|
|
|
|
return
|
|
end subroutine q65_dec2
|
|
|
|
subroutine q65_s1_to_s3(s1,iz,jz,ipk,jpk,LL,mode_q65,sync,s3)
|
|
|
|
! Copy from s1 or s1a into s3
|
|
|
|
real s1(iz,jz)
|
|
real s3(-64:LL-65,63)
|
|
real sync(85) !sync vector
|
|
|
|
i1=i0+ipk-64 + mode_q65
|
|
i2=i1+LL-1
|
|
if(i1.ge.1 .and. i2.le.iz) then
|
|
j=j0+jpk-7
|
|
n=0
|
|
do k=1,85
|
|
j=j+8
|
|
if(sync(k).gt.0.0) then
|
|
cycle
|
|
endif
|
|
n=n+1
|
|
if(j.ge.1 .and. j.le.jz) s3(-64:LL-65,n)=s1(i1:i2,j)
|
|
enddo
|
|
endif
|
|
|
|
return
|
|
end subroutine q65_s1_to_s3
|
|
|
|
end module q65
|