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https://github.com/saitohirga/WSJT-X.git
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44d2f446a2
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
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parameter (NMAX=60*12000)
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real dd(NMAX)
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do n=1,999
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read(60,end=999) dd
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call sync64(dd,dtx,f0,snr)
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write(*,1000) dtx,f0,snr
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1000 format('DT:',f6.2,' f0:',f7.1,' Sync S/N:',f10.1)
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enddo
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999 end program qratest
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subroutine sync64(dd,dtx,f0,snr)
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parameter (NMAX=60*12000)
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real dd(NMAX)
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real x(672000)
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real s0(0:16127)
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real s1(0:16127)
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real s2(0:16127)
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real s3(0:16127)
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real s0a(0:16127)
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real s1a(0:16127)
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real s2a(0:16127)
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real s3a(0:16127)
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integer icos7(0:6)
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integer ipk(1)
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complex cc(0:16127)
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complex c0(0:336000)
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complex c1(0:16127)
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complex c2(0:16127)
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complex c3(0:16127)
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equivalence (x,c0)
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data icos7/2,5,6,0,4,1,3/ !Costas 7x7 pattern
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twopi=8.0*atan(1.0)
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dfgen=12000.0/6912.0
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k=-1
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phi=0.
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do j=0,6
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dphi=twopi*icos7(j)*dfgen/4000.0
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do i=1,2304
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phi=phi + dphi
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if(phi.gt.twopi) phi=phi-twopi
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k=k+1
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cc(k)=cmplx(cos(phi),sin(phi))
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enddo
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enddo
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npts0=54*12000
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nfft1=672000
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nfft2=nfft1/3
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df1=12000.0/nfft1
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fac=2.0/nfft1
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x=fac*dd(1:nfft1)
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call four2a(c0,nfft1,1,-1,0) !Forward r2c FFT
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call four2a(c0,nfft2,1,1,1) !Inverse c2c FFT
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npts2=npts0/3 !Downsampled complex data length
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nfft3=16128
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nh3=nfft3/2
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df3=4000.0/nfft3
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iz=750.0/df3
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smax=0.
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jpk=0
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do j1=0,24000,20
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j2=j1 + 39*2304
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j3=j1 + 77*2304
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c1=1.e-4*c0(j1:j1+16127) * conjg(cc)
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call four2a(c1,nfft3,1,-1,1)
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c2=1.e-4*c0(j2:j2+16127) * conjg(cc)
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call four2a(c2,nfft3,1,-1,1)
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c3=1.e-4*c0(j3:j3+16127) * conjg(cc)
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call four2a(c3,nfft3,1,-1,1)
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do i=0,nfft3-1
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freq=i*df3
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s1(i)=real(c1(i))**2 + aimag(c1(i))**2
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s2(i)=real(c2(i))**2 + aimag(c2(i))**2
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s3(i)=real(c3(i))**2 + aimag(c3(i))**2
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enddo
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call smo121(s1,nfft3)
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call smo121(s2,nfft3)
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call smo121(s3,nfft3)
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s0=s1+s2+s3
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s=maxval(s0)
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if(s.gt.smax) then
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jpk=j1
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s0a=s0
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s1a=s1
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s2a=s2
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s3a=s3
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smax=s
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ipk=maxloc(s0)
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dtx=jpk/4000.0 - 1.0
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f0=(ipk(1)-1)*df3
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endif
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enddo
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sq=dot_product(s0a,s0a)
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ave=sum(s0a)/nfft3
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rms=sqrt(sq/nfft3 - ave*ave)
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snr=(smax-ave)/rms
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do i=0,nfft3-1
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freq=i*df3
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if(freq.gt.2500.0) exit
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write(14,1020) freq,s0a(i),s1a(i),s2a(i),s3a(i)
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1020 format(f10.3,4f12.1)
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enddo
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end subroutine sync64
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