WSJT-X/lib/detectmsk32.f90
Steven Franke 6b6700321a detectmsk32 now decodes syncless (32,16) messages. No SNR or t0 yet.
git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@6963 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
2016-07-29 15:30:26 +00:00

197 lines
4.4 KiB
Fortran

subroutine detectmsk32(cbig,n,mycall,hiscall,lines,nmessages,nutc,ntol,t00)
use timer_module, only: timer
parameter (NSPM=192, NPTS=3*NSPM, MAXSTEPS=7500, NFFT=3*NSPM, MAXCAND=5,NWIN=15*NSPM)
character*4 rpt(0:63)
character*6 mycall,hiscall
character*6 mycall0,hiscall0
character*22 msg,msgsent,msgreceived,allmessages(32)
character*80 lines(100)
complex cbig(n)
! complex cdat(0:NWIN-1)
complex cdat(0:n-1)
complex ctmp(NPTS)
! complex c(0:NWIN-1)
complex c(0:n-1)
complex cmsg(0:NSPM-1,0:63)
complex z
integer iloc(1)
integer ipk0(1)
integer indices(MAXSTEPS)
integer itone(144)
logical ismask(NFFT)
real a(3)
real detmet(-2:MAXSTEPS+3)
real detfer(MAXSTEPS)
real ferrs(MAXCAND)
real f2(64)
real peak(64)
real pp(12)
real p0(0:NSPM-1)
real p(0:NSPM-1)
real rcw(12)
real snrs(MAXCAND)
real s0(0:63)
real times(MAXCAND)
real tonespec(NFFT)
real*8 dt, df, fs, pi, twopi
logical first
equivalence (ipk0,ipk)
data first/.true./
save df,first,cb,cbr,fs,nhashes,pi,twopi,dt,rcw,pp,nmatchedfilter,cmsg,rpt,mycall0,hiscall0
if(first) then
nmatchedfilter=1
! define half-sine pulse and raised-cosine edge window
pi=4d0*datan(1d0)
twopi=8d0*datan(1d0)
fs=12000.0
dt=1.0/fs
df=fs/NFFT
do i=1,12
angle=(i-1)*pi/12.0
pp(i)=sin(angle)
rcw(i)=(1-cos(angle))/2
enddo
do i=0,30
if( i.lt.5 ) then
write(rpt(i),'(a1,i2.2,a1)') '-',abs(i-5)
write(rpt(i+31),'(a2,i2.2,a1)') 'R-',abs(i-5)
else
write(rpt(i),'(a1,i2.2,a1)') '+',i-5
write(rpt(i+31),'(a2,i2.2,a1)') 'R+',i-5
endif
enddo
rpt(62)='RRR '
rpt(63)='73 '
mycall0=' '
hiscall0=' '
first=.false.
endif
if(mycall .ne. mycall0 .or. hiscall .ne. hiscall0 ) then
freq=1500.0
nsym=32
dphi0=twopi*(freq-500)/12000.0
dphi1=twopi*(freq+500)/12000.0
do i=0,63
msg='<'//trim(mycall)//' '//trim(hiscall)//'> '//rpt(i)
call genmsk32(msg,msgsent,0,itone,itype)
phi=0.0
indx=0
nreps=1
do jrep=1,nreps
do isym=1,nsym
if( itone(isym) .eq. 0 ) then
dphi=dphi0
else
dphi=dphi1
endif
do j=1,6
cmsg(indx,i)=cmplx(cos(phi),sin(phi));
indx=indx+1
phi=mod(phi+dphi,twopi)
enddo
enddo
enddo
enddo
mycall0=mycall
hiscall0=hiscall
endif
cdat(0:n-1)=cbig
sbest=0.0
ibest=-1
do imsg=0,63
do idf=0,0
if( idf.eq.0 ) then
delf=0.0
else if( mod(idf,2).eq.1 ) then
delf=10*(idf+1)/2
else
delf=-10*idf/2
endif
a(1)=-delf
a(2:3)=0.
call twkfreq(cdat,c,n,12000.0,a)
smax=0.
p=0.
fac=1.0/192
do j=0,n-NSPM-1,2
z=fac*dot_product(c(j:j+NSPM-1),cmsg(0:NSPM-1,imsg))
s=real(z)**2 + aimag(z)**2
k=mod(j,NSPM)
p(k)=p(k)+s
if( s.gt.smax) then
smax=s
jpk=j
if( smax.gt.sbest) then
sbest=smax
p0=p
ibest=imsg
f0=1500+delf
endif
endif
enddo ! time loop
s0(imsg)=smax
enddo ! frequency loop
enddo ! message loop
ipk0=maxloc(p0)
ps=0.
sq=0.
ns=0
pmax=0.
do i=0,NSPM-1,2
j=ipk-i
if(j.gt.96) j=j-192
if(j.lt.-96) j=j+192
if(abs(j).gt.4) then
ps=ps+p0(i)
sq=sq+p0(i)**2
ns=ns+1
endif
enddo
avep=ps/ns
rmsp=sqrt(sq/ns-avep*avep)
p0=(p0-avep)/rmsp
p1=maxval(p0)
! do i=0,NSPM-1,2
! write(14,1030) i,i/12000.0,p0(i)
!1030 format(i5,f10.6,f10.3)
! enddo
ave=(sum(s0)-sbest)/63
s0=s0-ave
s1=sbest-ave
s2=0.
do i=0,63
if(i.ne.ibest .and. s0(i).gt.s2) s2=s0(i)
! write(15,1020) i,idf,jpk/12000.0,s0(i)
!1020 format(2i6,2f10.2)
enddo
r1=s1/s2
r2=r1+p1
msg=" "
! write(*,'(i6.6,3f7.1,i5,2x,a22)') nutc,r1,p1,r2,ibest
nmessages=0
lines=char(0)
if(r2.gt.7.0) then
t0=0.0
nsnr=0.0
msgreceived=' '
nrxrpt=iand(ibest,63)
nmessages=1
write(msgreceived,'(a1,a,1x,a,a1,1x,a4)') "<",trim(mycall), &
trim(hiscall),">",rpt(nrxrpt)
write(lines(nmessages),1021) nutc,nsnr,t0,nint(f0),msgreceived
1021 format(i6.6,i4,f5.1,i5,' & ',a22)
endif
return
end subroutine detectmsk32