mirror of
https://github.com/saitohirga/WSJT-X.git
synced 2024-11-23 04:38:37 -05:00
7134dbb435
Simplified and (I think) corrected recvpkt.F90. git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/map65@991 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
116 lines
3.2 KiB
Fortran
116 lines
3.2 KiB
Fortran
subroutine symspec(id,kbuf,kk,kkdone,nutc,newdat)
|
|
|
|
! Compute spectra at four polarizations, using half-symbol steps.
|
|
|
|
parameter (NSMAX=60*96000)
|
|
integer*2 id(4,NSMAX,2)
|
|
complex z
|
|
real*8 ts,hsym
|
|
include 'spcom.f90'
|
|
include 'gcom2.f90'
|
|
complex cx(NFFT),cy(NFFT) ! pad to 32k with zeros
|
|
data kbuf0/-999/,n/0/
|
|
save
|
|
|
|
kkk=kk
|
|
if(kbuf.eq.2) kkk=kk-5760000
|
|
fac=0.0002
|
|
hsym=2048.d0*96000.d0/11025.d0 !Samples per half symbol
|
|
npts=hsym !Integral samples per half symbol
|
|
ntot=322 !Half symbols per transmission
|
|
! ntot=279 !Half symbols in 51.8 sec
|
|
|
|
if(kbuf.ne.kbuf0 .or. ndiskdat.eq.1) then
|
|
kkdone=0
|
|
kbuf0=kbuf
|
|
ts=1.d0 - hsym
|
|
n=0
|
|
do ip=1,4
|
|
do i=1,NFFT
|
|
szavg(ip,i)=0.
|
|
enddo
|
|
enddo
|
|
endif
|
|
|
|
do nn=1,ntot
|
|
i0=ts+hsym !Starting sample pointer
|
|
if((i0+npts-1).gt.kkk) go to 998 !See if we have enough points
|
|
i1=ts+2*hsym !Next starting sample pointer
|
|
ts=ts+hsym !OK, update the exact sample pointer
|
|
do i=1,npts !Copy data to FFT arrays
|
|
xr=fac*id(1,i0+i,kbuf)
|
|
xi=fac*id(2,i0+i,kbuf)
|
|
cx(i)=cmplx(xr,xi)
|
|
yr=fac*id(3,i0+i,kbuf)
|
|
yi=fac*id(4,i0+i,kbuf)
|
|
cy(i)=cmplx(yr,yi)
|
|
enddo
|
|
|
|
do i=npts+1,NFFT !Pad to 32k with zeros
|
|
cx(i)=0.
|
|
cy(i)=0.
|
|
enddo
|
|
|
|
call four2a(cx,NFFT,1,1,1) !Do the FFTs
|
|
call four2a(cy,NFFT,1,1,1)
|
|
|
|
n=n+1
|
|
do i=1,NFFT !Save and accumulate power spectra
|
|
sx=real(cx(i))**2 + aimag(cx(i))**2
|
|
ssz(1,n,i)=sx ! Pol = 0
|
|
szavg(1,i)=szavg(1,i) + sx
|
|
|
|
z=cx(i) + cy(i)
|
|
s45=0.5*(real(z)**2 + aimag(z)**2)
|
|
ssz(2,n,i)=s45 ! Pol = 45
|
|
szavg(2,i)=szavg(2,i) + s45
|
|
|
|
sy=real(cy(i))**2 + aimag(cy(i))**2
|
|
ssz(3,n,i)=sy ! Pol = 90
|
|
szavg(3,i)=szavg(3,i) + sy
|
|
|
|
z=cx(i) - cy(i)
|
|
s135=0.5*(real(z)**2 + aimag(z)**2)
|
|
ssz(4,n,i)=s135 ! Pol = 135
|
|
szavg(4,i)=szavg(4,i) + s135
|
|
|
|
z=cx(i)*conjg(cy(i))
|
|
|
|
! Leif's formula:
|
|
! ss5(n,i)=0.5*(sx+sy) + (real(z)**2 + aimag(z)**2 -
|
|
! + sx*sy)/(sx+sy)
|
|
|
|
! Leif's suggestion:
|
|
! ss5(n,i)=max(sx,s45,sy,s135)
|
|
|
|
! Linearly polarized component, from the Stokes parameters:
|
|
q=sx - sy
|
|
u=2.0*real(z)
|
|
! v=2.0*aimag(z)
|
|
ssz5(n,i)=0.707*sqrt(q*q + u*u)
|
|
|
|
enddo
|
|
! if(n.eq.ntot) then
|
|
if(n.ge.279) then
|
|
call move(ssz5,ss5,322*NFFT)
|
|
write(utcdata,1002) nutc
|
|
1002 format(i4.4)
|
|
utcdata=utcdata(1:2)//':'//utcdata(3:4)
|
|
newspec=1
|
|
call move(ssz,ss,4*322*NFFT)
|
|
call move(szavg,savg,4*NFFT)
|
|
newdat=1
|
|
ndecoding=1
|
|
go to 999
|
|
endif
|
|
kkdone=i1-1
|
|
nhsym=n
|
|
call sleep_msec(0)
|
|
enddo
|
|
|
|
998 kkdone=i1-1
|
|
999 continue
|
|
|
|
return
|
|
end subroutine symspec
|