mirror of
https://github.com/saitohirga/WSJT-X.git
synced 2024-09-07 22:06:38 -04:00
git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@6936 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
117 lines
2.4 KiB
Fortran
117 lines
2.4 KiB
Fortran
program qratest
|
|
|
|
parameter (NMAX=60*12000)
|
|
real dd(NMAX)
|
|
|
|
do n=1,999
|
|
read(60,end=999) dd
|
|
call sync64(dd,dtx,f0,snr)
|
|
write(*,1000) dtx,f0,snr
|
|
1000 format('DT:',f6.2,' f0:',f7.1,' Sync S/N:',f10.1)
|
|
enddo
|
|
|
|
999 end program qratest
|
|
|
|
subroutine sync64(dd,dtx,f0,snr)
|
|
parameter (NMAX=60*12000)
|
|
real dd(NMAX)
|
|
real x(672000)
|
|
|
|
real s0(0:16127)
|
|
real s1(0:16127)
|
|
real s2(0:16127)
|
|
real s3(0:16127)
|
|
|
|
real s0a(0:16127)
|
|
real s1a(0:16127)
|
|
real s2a(0:16127)
|
|
real s3a(0:16127)
|
|
|
|
integer icos7(0:6)
|
|
integer ipk(1)
|
|
|
|
complex cc(0:16127)
|
|
complex c0(0:336000)
|
|
complex c1(0:16127)
|
|
complex c2(0:16127)
|
|
complex c3(0:16127)
|
|
equivalence (x,c0)
|
|
data icos7/2,5,6,0,4,1,3/ !Costas 7x7 pattern
|
|
|
|
twopi=8.0*atan(1.0)
|
|
dfgen=12000.0/6912.0
|
|
k=-1
|
|
phi=0.
|
|
do j=0,6
|
|
dphi=twopi*icos7(j)*dfgen/4000.0
|
|
do i=1,2304
|
|
phi=phi + dphi
|
|
if(phi.gt.twopi) phi=phi-twopi
|
|
k=k+1
|
|
cc(k)=cmplx(cos(phi),sin(phi))
|
|
enddo
|
|
enddo
|
|
|
|
npts0=54*12000
|
|
nfft1=672000
|
|
nfft2=nfft1/3
|
|
df1=12000.0/nfft1
|
|
fac=2.0/nfft1
|
|
x=fac*dd(1:nfft1)
|
|
call four2a(c0,nfft1,1,-1,0) !Forward r2c FFT
|
|
|
|
call four2a(c0,nfft2,1,1,1) !Inverse c2c FFT
|
|
npts2=npts0/3 !Downsampled complex data length
|
|
nfft3=16128
|
|
nh3=nfft3/2
|
|
df3=4000.0/nfft3
|
|
iz=750.0/df3
|
|
smax=0.
|
|
jpk=0
|
|
do j1=0,24000,20
|
|
j2=j1 + 39*2304
|
|
j3=j1 + 77*2304
|
|
c1=1.e-4*c0(j1:j1+16127) * conjg(cc)
|
|
call four2a(c1,nfft3,1,-1,1)
|
|
c2=1.e-4*c0(j2:j2+16127) * conjg(cc)
|
|
call four2a(c2,nfft3,1,-1,1)
|
|
c3=1.e-4*c0(j3:j3+16127) * conjg(cc)
|
|
call four2a(c3,nfft3,1,-1,1)
|
|
do i=0,nfft3-1
|
|
freq=i*df3
|
|
s1(i)=real(c1(i))**2 + aimag(c1(i))**2
|
|
s2(i)=real(c2(i))**2 + aimag(c2(i))**2
|
|
s3(i)=real(c3(i))**2 + aimag(c3(i))**2
|
|
enddo
|
|
call smo121(s1,nfft3)
|
|
call smo121(s2,nfft3)
|
|
call smo121(s3,nfft3)
|
|
s0=s1+s2+s3
|
|
s=maxval(s0)
|
|
if(s.gt.smax) then
|
|
jpk=j1
|
|
s0a=s0
|
|
s1a=s1
|
|
s2a=s2
|
|
s3a=s3
|
|
smax=s
|
|
ipk=maxloc(s0)
|
|
dtx=jpk/4000.0 - 1.0
|
|
f0=(ipk(1)-1)*df3
|
|
endif
|
|
enddo
|
|
|
|
sq=dot_product(s0a,s0a)
|
|
ave=sum(s0a)/nfft3
|
|
rms=sqrt(sq/nfft3 - ave*ave)
|
|
snr=(smax-ave)/rms
|
|
|
|
do i=0,nfft3-1
|
|
freq=i*df3
|
|
if(freq.gt.2500.0) exit
|
|
write(14,1020) freq,s0a(i),s1a(i),s2a(i),s3a(i)
|
|
1020 format(f10.3,4f12.1)
|
|
enddo
|
|
|
|
end subroutine sync64
|