mirror of
https://github.com/saitohirga/WSJT-X.git
synced 2024-11-20 02:52:00 -05:00
bbbcae9233
git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@7933 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
283 lines
9.3 KiB
Fortran
283 lines
9.3 KiB
Fortran
subroutine ft8b(dd0,newdat,nfqso,ndepth,lapon,napwid,lsubtract,iaptype,icand, &
|
|
sync0,f1,xdt,apsym,nharderrors,dmin,nbadcrc,iap,ipass,iera,message,xsnr)
|
|
|
|
use timer_module, only: timer
|
|
include 'ft8_params.f90'
|
|
parameter(NRECENT=10,NP2=2812)
|
|
character message*22,msgsent*22
|
|
character*12 recent_calls(NRECENT)
|
|
real a(5)
|
|
real s1(0:7,ND),s2(0:7,NN)
|
|
real ps(0:7)
|
|
real rxdata(3*ND),rxdatap(3*ND)
|
|
real llr(3*ND),llra(3*ND),llr0(3*ND),llrap(3*ND) !Soft symbols
|
|
real dd0(15*12000)
|
|
integer*1 decoded(KK),apmask(3*ND),cw(3*ND)
|
|
integer*1 msgbits(KK)
|
|
integer apsym(KK),rr73(11),cq(28)
|
|
integer itone(NN)
|
|
complex cd0(3200)
|
|
complex ctwk(32)
|
|
complex csymb(32)
|
|
logical newdat,lsubtract,lapon
|
|
data rr73/-1,1,1,1,1,1,1,-1,1,1,-1/
|
|
data cq/1,1,1,1,1,-1,1,-1,-1,-1,-1,-1,1,-1,-1,-1,-1,-1,1,1,-1,-1,-1,1,1,-1,-1,1/
|
|
|
|
max_iterations=30
|
|
nharderrors=-1
|
|
fs2=12000.0/NDOWN
|
|
dt2=1.0/fs2
|
|
twopi=8.0*atan(1.0)
|
|
delfbest=0.
|
|
ibest=0
|
|
|
|
call timer('ft8_down',0)
|
|
call ft8_downsample(dd0,newdat,f1,cd0) !Mix f1 to baseband and downsample
|
|
call timer('ft8_down',1)
|
|
|
|
i0=nint((xdt+0.5)*fs2) !Initial guess for start of signal
|
|
smax=0.0
|
|
do idt=i0-8,i0+8 !Search over +/- one quarter symbol
|
|
call sync8d(cd0,idt,ctwk,0,sync)
|
|
if(sync.gt.smax) then
|
|
smax=sync
|
|
ibest=idt
|
|
endif
|
|
enddo
|
|
xdt2=ibest*dt2 !Improved estimate for DT
|
|
|
|
! Now peak up in frequency
|
|
i0=nint(xdt2*fs2)
|
|
smax=0.0
|
|
do ifr=-5,5 !Search over +/- 2.5 Hz
|
|
delf=ifr*0.5
|
|
dphi=twopi*delf*dt2
|
|
phi=0.0
|
|
do i=1,32
|
|
ctwk(i)=cmplx(cos(phi),sin(phi))
|
|
phi=mod(phi+dphi,twopi)
|
|
enddo
|
|
call sync8d(cd0,i0,ctwk,1,sync)
|
|
if( sync .gt. smax ) then
|
|
smax=sync
|
|
delfbest=delf
|
|
endif
|
|
enddo
|
|
a=0.0
|
|
a(1)=-delfbest
|
|
call twkfreq1(cd0,NP2,fs2,a,cd0)
|
|
xdt=xdt2
|
|
f1=f1+delfbest !Improved estimate of DF
|
|
|
|
call sync8d(cd0,i0,ctwk,2,sync)
|
|
|
|
j=0
|
|
do k=1,NN
|
|
i1=ibest+(k-1)*32
|
|
csymb=cmplx(0.0,0.0)
|
|
if( i1.ge.1 .and. i1+31 .le. NP2 ) csymb=cd0(i1:i1+31)
|
|
call four2a(csymb,32,1,-1,1)
|
|
s2(0:7,k)=abs(csymb(1:8))
|
|
enddo
|
|
j=0
|
|
do k=1,NN
|
|
if(k.le.7) cycle
|
|
if(k.ge.37 .and. k.le.43) cycle
|
|
if(k.gt.72) cycle
|
|
j=j+1
|
|
s1(0:7,j)=s2(0:7,k)
|
|
enddo
|
|
|
|
do j=1,ND
|
|
ps=s1(0:7,j)
|
|
where (ps.gt.0.0) ps=log(ps)
|
|
r1=max(ps(1),ps(3),ps(5),ps(7))-max(ps(0),ps(2),ps(4),ps(6))
|
|
r2=max(ps(2),ps(3),ps(6),ps(7))-max(ps(0),ps(1),ps(4),ps(5))
|
|
r4=max(ps(4),ps(5),ps(6),ps(7))-max(ps(0),ps(1),ps(2),ps(3))
|
|
i4=3*j-2
|
|
i2=3*j-1
|
|
i1=3*j
|
|
rxdata(i4)=r4
|
|
rxdata(i2)=r2
|
|
rxdata(i1)=r1
|
|
rxdatap(i4)=r4
|
|
rxdatap(i2)=r2
|
|
rxdatap(i1)=r1
|
|
! When bits 88:115 are set as ap bits, bit 115 lives in symbol 39 along
|
|
! with no-ap bits 116 and 117. Take care of metrics for bits 116 and 117.
|
|
! if(j.eq.39) then ! take care of bits that live in symbol 39
|
|
! if(apsym(28).lt.0) then
|
|
! rxdatap(i2)=max(ps(2),ps(3))-max(ps(0),ps(1))
|
|
! rxdatap(i1)=max(ps(1),ps(3))-max(ps(0),ps(2))
|
|
! else
|
|
! rxdatap(i2)=max(ps(6),ps(7))-max(ps(4),ps(5))
|
|
! rxdatap(i1)=max(ps(5),ps(7))-max(ps(4),ps(6))
|
|
! endif
|
|
! endif
|
|
! When bits 116:143 are set as ap bits, bit 115 lives in symbol 39 along
|
|
! with ap bits 116 and 117. Take care of metric for bit 115.
|
|
if(j.eq.39) then ! take care of bit 115
|
|
iii=2*(apsym(29)+1)/2 + (apsym(30)+1)/2 ! known values of bits 116 & 117
|
|
if(iii.eq.0) rxdatap(i4)=ps(4)-ps(0)
|
|
if(iii.eq.1) rxdatap(i4)=ps(5)-ps(1)
|
|
if(iii.eq.2) rxdatap(i4)=ps(6)-ps(2)
|
|
if(iii.eq.3) rxdatap(i4)=ps(7)-ps(3)
|
|
endif
|
|
! bit 144 lives in symbol 48 and will be 1 if it is set as an ap bit.
|
|
! take care of metrics for bits 142 and 143
|
|
if(j.eq.48) then ! bit 144 is always 1
|
|
rxdatap(i4)=max(ps(5),ps(7))-max(ps(1),ps(3))
|
|
rxdatap(i2)=max(ps(3),ps(7))-max(ps(1),ps(5))
|
|
endif
|
|
! bit 154 lives in symbol 52 and will be 0 if it is set as an ap bit
|
|
! take care of metrics for bits 155 and 156
|
|
if(j.eq.52) then ! bit 154 will be 0 if it is set as an ap bit.
|
|
rxdatap(i2)=max(ps(2),ps(3))-max(ps(0),ps(1))
|
|
rxdatap(i1)=max(ps(1),ps(3))-max(ps(0),ps(2))
|
|
endif
|
|
enddo
|
|
|
|
rxav=sum(rxdata)/(3.0*ND)
|
|
rx2av=sum(rxdata*rxdata)/(3.0*ND)
|
|
var=rx2av-rxav*rxav
|
|
if( var .gt. 0.0 ) then
|
|
rxsig=sqrt(var)
|
|
else
|
|
rxsig=sqrt(rx2av)
|
|
endif
|
|
rxdata=rxdata/rxsig
|
|
! Let's just assume that rxsig is OK for rxdatap too...
|
|
rxdatap=rxdatap/rxsig
|
|
|
|
ss=0.84
|
|
llr0=2.0*rxdata/(ss*ss)
|
|
llra=2.0*rxdatap/(ss*ss) ! llr's for use with ap
|
|
apmag=4.0
|
|
! If DxCall exists, only do "MyCall DxCall ???" for candidates within nfqso +/- napwid
|
|
nap=0
|
|
if(lapon.and.(ndepth.eq.3).and.(iaptype.eq.1 .or. (iaptype.eq.2.and.abs(nfqso-f1).le.napwid))) nap=2
|
|
if(lapon.and.(ndepth.eq.3).and.iaptype.eq.2.and.abs(nfqso-f1).gt.napwid) nap=1
|
|
|
|
do iap=0,nap !### Temporary ###
|
|
nera=1
|
|
if(iap.eq.0) nera=3
|
|
do iera=1,nera
|
|
llr=llr0
|
|
nblank=0
|
|
if(nera.eq.3 .and. iera.eq.1) nblank=0
|
|
if(nera.eq.3 .and. iera.eq.2) nblank=24
|
|
if(nera.eq.3 .and. iera.eq.3) nblank=48
|
|
if(nblank.gt.0) llr(1:nblank)=0.
|
|
if(iap.eq.0) then
|
|
apmask=0
|
|
! apmask(160:162)=1
|
|
llrap=llr
|
|
! llrap(160:162)=apmag*apsym(73:75)/ss
|
|
endif
|
|
if(iaptype.eq.1) then
|
|
if(iap.eq.1) then ! look for plain CQ
|
|
apmask=0
|
|
apmask(88:115)=1 ! plain CQ
|
|
apmask(144)=1 ! not free text
|
|
! apmask(160:162)=1 ! 3 extra bits
|
|
llrap=llr
|
|
llrap(88:115)=apmag*cq/ss
|
|
llrap(116:117)=llra(116:117)
|
|
llrap(142:143)=llra(142:143)
|
|
llrap(144)=-apmag/ss
|
|
! llrap(160:162)=apmag*apsym(73:75)/ss
|
|
endif
|
|
if(iap.eq.2) then ! look for mycall
|
|
apmask=0
|
|
apmask(88:115)=1 ! mycall
|
|
apmask(144)=1 ! not free text
|
|
! apmask(160:162)=1 ! 3 extra bits
|
|
llrap=llr
|
|
llrap(88:115)=apmag*apsym(1:28)/ss
|
|
llrap(116:117)=llra(116:117)
|
|
llrap(142:143)=llra(142:143)
|
|
llrap(144)=-apmag/ss
|
|
! llrap(160:162)=apmag*apsym(73:75)/ss
|
|
endif
|
|
endif
|
|
if(iaptype.eq.2) then
|
|
if(iap.eq.1) then ! look for dxcall
|
|
apmask=0
|
|
! apmask(88:115)=1 ! mycall
|
|
apmask(116:143)=1 ! hiscall
|
|
apmask(144)=1 ! not free text
|
|
! apmask(160:162)=1 ! 3 extra bits
|
|
llrap=llr
|
|
! llrap(88:143)=apmag*apsym(1:56)/ss
|
|
llrap(115)=llra(115)
|
|
llrap(116:143)=apmag*apsym(29:56)/ss
|
|
llrap(144)=-apmag/ss
|
|
! llrap(160:162)=apmag*apsym(73:75)/ss
|
|
endif
|
|
if(iap.eq.2) then ! look mycall, dxcall
|
|
apmask=0
|
|
apmask(88:115)=1 ! mycall
|
|
apmask(116:143)=1 ! hiscall
|
|
apmask(144)=1 ! not free text
|
|
! apmask(144:154)=1 ! RRR or 73
|
|
! apmask(160:162)=1 ! 3 extra bits
|
|
llrap=llr
|
|
llrap(88:143)=apmag*apsym(1:56)/ss
|
|
llrap(144)=-apmag/ss
|
|
! llrap(144:154)=apmag*rr73/ss
|
|
! llrap(155:156)=llra(155:156)
|
|
! llrap(160:162)=apmag*apsym(73:75)/ss
|
|
endif
|
|
endif
|
|
|
|
cw=0
|
|
call timer('bpd174 ',0)
|
|
call bpdecode174(llrap,apmask,max_iterations,decoded,cw,nharderrors, &
|
|
niterations)
|
|
call timer('bpd174 ',1)
|
|
dmin=0.0
|
|
if(ndepth.eq.3 .and. nharderrors.lt.0) then
|
|
norder=1
|
|
if(abs(nfqso-f1).le.napwid) norder=2 !Decode using norder=2 within napwid of nfqso.
|
|
call timer('osd174 ',0)
|
|
call osd174(llrap,apmask,norder,decoded,cw,nharderrors,dmin)
|
|
call timer('osd174 ',1)
|
|
endif
|
|
nbadcrc=1
|
|
message=' '
|
|
xsnr=-99.0
|
|
if(count(cw.eq.0).eq.174) cycle !Reject the all-zero codeword
|
|
if(any(decoded(75:75).ne.0)) cycle !Reject if any of the 3 extra bits are nonzero
|
|
if(nharderrors.ge.0 .and. nharderrors+dmin.lt.60.0 .and. &
|
|
.not.(sync.lt.2.0 .and. nharderrors.gt.35) .and. &
|
|
.not.(iap.gt.0 .and. nharderrors.gt.39) .and. &
|
|
.not.(iera.ge.2 .and. nharderrors.gt.30) &
|
|
) then
|
|
call chkcrc12a(decoded,nbadcrc)
|
|
else
|
|
nharderrors=-1
|
|
cycle
|
|
endif
|
|
if(nbadcrc.eq.0) then
|
|
call extractmessage174(decoded,message,ncrcflag,recent_calls,nrecent)
|
|
call genft8(message,msgsent,msgbits,itone)
|
|
if(lsubtract) call subtractft8(dd0,itone,f1,xdt2)
|
|
xsig=0.0
|
|
xnoi=0.0
|
|
do i=1,79
|
|
xsig=xsig+s2(itone(i),i)**2
|
|
ios=mod(itone(i)+4,7)
|
|
xnoi=xnoi+s2(ios,i)**2
|
|
enddo
|
|
xsnr=0.001
|
|
if(xnoi.gt.0 .and. xnoi.lt.xsig) xsnr=xsig/xnoi-1.0
|
|
xsnr=10.0*log10(xsnr)-27.0
|
|
if(xsnr .lt. -24.0) xsnr=-24.0
|
|
return
|
|
endif
|
|
enddo
|
|
enddo
|
|
|
|
return
|
|
end subroutine ft8b
|