WSJT-X/libm65/symspec.f90

196 lines
5.8 KiB
Fortran
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subroutine symspec(k,nxpol,ndiskdat,nb,nbslider,idphi,nfsample,fgreen, &
iqadjust,iqapply,gainx,gainy,phasex,phasey,rejectx,rejecty, &
pxdb,pydb,ssz5a,nkhz,ihsym,nzap,slimit,lstrong)
! k pointer to the most recent new data
! nxpol 0/1 to indicate single- or dual-polarization
! ndiskdat 0/1 to indicate if data from disk
! nb 0/1 status of noise blanker
! idphi Phase correction for Y channel, degrees
! nfsample sample rate (Hz)
! fgreen Frequency of green marker in I/Q calibrate mode (-48.0 to +48.0 kHz)
! iqadjust 0/1 to indicate whether IQ adjustment is active
! iqapply 0/1 to indicate whether to apply I/Q calibration
! pxdb power in x channel (0-60 dB)
! pydb power in y channel (0-60 dB)
! ssz5a polarized spectrum, for waterfall display
! nkhz integer kHz portion of center frequency, e.g., 125 for 144.125
! ihsym index number of this half-symbol (1-322)
! nzap number of samples zero'ed by noise blanker
parameter (NSMAX=60*96000) !Total sample intervals per minute
parameter (NFFT=32768) !Length of FFTs
real*8 ts,hsym
real*8 fcenter
common/datcom/dd(4,5760000),ss(4,322,NFFT),savg(4,NFFT),fcenter,nutc,junk(34)
real*4 ssz5a(NFFT),w(NFFT)
complex z,zfac
complex zsumx,zsumy
complex cx(NFFT),cy(NFFT)
complex cx0(0:1023),cx1(0:1023)
complex cy0(0:1023),cy1(0:1023)
logical*1 lstrong(0:1023)
data rms/999.0/,k0/99999999/,nadjx/0/,nadjy/0/
save
if(k.gt.5751000) go to 999
if(k.lt.NFFT) then
ihsym=0
go to 999 !Wait for enough samples to start
endif
if(k0.eq.99999999) then
pi=4.0*atan(1.0)
do i=1,NFFT
w(i)=(sin(i*pi/NFFT))**2
enddo
endif
if(k.lt.k0) then
ts=1.d0 - hsym
savg=0.
ihsym=0
k1=0
dd(1:4,k+1:5760000)=0. !### Should not be needed ??? ###
endif
k0=k
nzap=0
sigmas=1.5*(10.0**(0.01*nbslider)) + 0.7
peaklimit=sigmas*max(10.0,rms)
faclim=3.0
px=0.
py=0.
iqapply0=0
iqadjust0=0
if(iqadjust.ne.0) iqapply0=0
nwindow=2
! nwindow=0 !### No wondowing ###
nfft2=1024
kstep=nfft2
if(nwindow.ne.0) kstep=nfft2/2
nblks=(k-k1)/kstep
do nblk=1,nblks
j=k1+1
do i=0,nfft2-1
cx0(i)=cmplx(dd(1,j+i),dd(2,j+i))
if(nxpol.ne.0) cy0(i)=cmplx(dd(3,j+i),dd(4,j+i))
enddo
call timf2(k,nxpol,nfft2,nwindow,nb,peaklimit,iqadjust0,iqapply0,faclim, &
cx0,cy0,gainx,gainy,phasex,phasey,cx1,cy1,slimit,lstrong, &
px,py,nzap)
do i=0,kstep-1
dd(1,j+i)=real(cx1(i))
dd(2,j+i)=aimag(cx1(i))
if(nxpol.ne.0) then
dd(3,j+i)=real(cy1(i))
dd(4,j+i)=aimag(cy1(i))
endif
enddo
k1=k1+kstep
enddo
hsym=2048.d0*96000.d0/11025.d0 !Samples per JT65 half-symbol
if(nfsample.eq.95238) hsym=2048.d0*95238.1d0/11025.d0
npts=NFFT !Samples used in each half-symbol FFT
ihsym=ihsym+1
ja=ts+hsym !Index of first sample
jb=ja+npts-1 !Last sample
ts=ts+hsym
i=0
fac=0.0002
dphi=idphi/57.2957795
zfac=fac*cmplx(cos(dphi),sin(dphi))
do j=ja,jb !Copy data into cx, cy
x1=dd(1,j)
x2=dd(2,j)
if(nxpol.ne.0) then
x3=dd(3,j)
x4=dd(4,j)
else
x3=0.
x4=0.
endif
i=i+1
cx(i)=fac*cmplx(x1,x2)
cy(i)=zfac*cmplx(x3,x4) !NB: cy includes dphi correction
enddo
if(nzap/178.lt.50 .and. (ndiskdat.eq.0 .or. ihsym.lt.280)) then
nsum=nblks*kstep - nzap
if(nsum.le.0) nsum=1
rmsx=sqrt(0.5*px/nsum)
rmsy=sqrt(0.5*py/nsum)
rms=rmsx
if(nxpol.ne.0) rms=sqrt((px+py)/(4.0*nsum))
endif
pxdb=0.
pydb=0.
if(rmsx.gt.1.0) pxdb=20.0*log10(rmsx)
if(rmsy.gt.1.0) pydb=20.0*log10(rmsy)
if(pxdb.gt.60.0) pxdb=60.0
if(pydb.gt.60.0) pydb=60.0
cx=w*cx !Apply window for 2nd forward FFT
if(nxpol.ne.0) cy=w*cy
call four2a(cx,NFFT,1,1,1) !Second forward FFT
if(iqadjust.eq.0) nadjx=0
if(iqadjust.ne.0 .and. nadjx.lt.50) call iqcal(nadjx,cx,NFFT,gainx,phasex, &
zsumx,ipkx,rejectx0)
if(iqapply.ne.0) call iqfix(cx,NFFT,gainx,phasex)
if(nxpol.ne.0) then
call four2a(cy,NFFT,1,1,1)
if(iqadjust.eq.0) nadjy=0
if(iqadjust.ne.0 .and. nadjy.lt.50) call iqcal(nadjy,cy,NFFT,gainy,phasey,&
zsumy,ipky,rejecty)
if(iqapply.ne.0) call iqfix(cy,NFFT,gainy,phasey)
endif
n=ihsym
do i=1,NFFT
sx=real(cx(i))**2 + aimag(cx(i))**2
ss(1,n,i)=sx ! Pol = 0
savg(1,i)=savg(1,i) + sx
if(nxpol.ne.0) then
z=cx(i) + cy(i)
s45=0.5*(real(z)**2 + aimag(z)**2)
ss(2,n,i)=s45 ! Pol = 45
savg(2,i)=savg(2,i) + s45
sy=real(cy(i))**2 + aimag(cy(i))**2
ss(3,n,i)=sy ! Pol = 90
savg(3,i)=savg(3,i) + sy
z=cx(i) - cy(i)
s135=0.5*(real(z)**2 + aimag(z)**2)
ss(4,n,i)=s135 ! Pol = 135
savg(4,i)=savg(4,i) + s135
z=cx(i)*conjg(cy(i))
q=sx - sy
u=2.0*real(z)
ssz5a(i)=0.707*sqrt(q*q + u*u) !Spectrum of linear polarization
! Leif's formula:
! ssz5a(i)=0.5*(sx+sy) + (real(z)**2 + aimag(z)**2 - sx*sy)/(sx+sy)
else
ssz5a(i)=sx
endif
enddo
if(ihsym.eq.278) then
if(iqadjust.ne.0 .and. ipkx.ne.0 .and. ipky.ne.0) then
rejectx=10.0*log10(savg(1,1+nfft-ipkx)/savg(1,1+ipkx))
rejecty=10.0*log10(savg(3,1+nfft-ipky)/savg(3,1+ipky))
endif
endif
nkhz=nint(1000.d0*(fcenter-int(fcenter)))
if(fcenter.eq.0.d0) nkhz=125
999 return
end subroutine symspec