Initial Commit

2018-02-08 21:28:33 -05:00
commit 678c1d3966
14352 changed files with 3176737 additions and 0 deletions
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+subroutine getfc2w(c,csync,npeaks,fs,fc1,fpks)
+
+  include 'wsprlf_params.f90'
+
+  complex c(0:NZ-1)                     !Complex waveform
+  complex cs(0:NZ-1)                    !For computing spectrum
+  complex csync(0:NZ-1)                 !Sync symbols only, from cbb
+  real a(5)
+  real freqs(413),sp2(413),fpks(npeaks)
+  integer pkloc(1)
+
+  df=fs/NZ
+  baud=fs/NSPS
+  a(1)=-fc1
+  a(2:5)=0.
+  call twkfreq1(c,NZ,fs,a,cs)         !Mix down by fc1
+
+! Filter, square, then FFT to get refined carrier frequency fc2.
+  call four2a(cs,NZ,1,-1,1)          !To freq domain
+
+  ia=nint(0.75*baud/df) 
+  cs(ia:NZ-1-ia)=0.                  !Save only freqs around fc1
+  call four2a(cs,NZ,1,1,1)           !Back to time domain
+  cs=cs/NZ
+  cs=cs*cs                           !Square the data
+  call four2a(cs,NZ,1,-1,1)          !Compute squared spectrum
+
+! Find two peaks separated by baud
+  pmax=0.
+  fc2=0.
+  ja=nint(0.3*baud/df)
+  k=1
+  do j=-ja,ja
+     f2=j*df
+     ia=nint((f2-0.5*baud)/df)
+     if(ia.lt.0) ia=ia+NZ
+     ib=nint((f2+0.5*baud)/df)
+     p=real(cs(ia))**2 + aimag(cs(ia))**2 +                        &
+          real(cs(ib))**2 + aimag(cs(ib))**2           
+     if(p.gt.pmax) then
+        pmax=p
+        fc2=0.5*f2
+     endif
+     freqs(k)=0.5*f2
+     sp2(k)=p
+     k=k+1
+!           write(52,1200) f2,p,db(p)
+!1200       format(f10.3,2f15.3)
+  enddo
+
+  do i=1,npeaks
+    pkloc=maxloc(sp2)
+    ipk=pkloc(1)
+    fpks(i)=freqs(ipk)
+    ipk0=max(1,ipk-1)
+    ipk1=min(413,ipk+1)
+!    ipk0=ipk
+!    ipk1=ipk
+    sp2(ipk0:ipk1)=0.0
+!write(*,*) i,fpks(i),fc2
+  enddo
+ 
+  a(1)=-fc1
+  a(2:5)=0.
+  call twkfreq1(c,NZ,fs,a,cs)         !Mix down by fc1
+  cs=cs*conjg(csync)
+  call four2a(cs,NZ,1,-1,1)          !To freq domain
+  pmax=0.
+  do i=0,NZ-1
+     f=i*df
+     if(i.gt.NZ/2) f=(i-NZ)*df
+     p=real(cs(i))**2 + aimag(cs(i))**2
+!     write(51,3001) f,p,db(p)
+!3001 format(f10.3,e12.3,f10.3)
+     if(p.gt.pmax) then
+        pmax=p
+        fc3=f
+     endif
+  enddo
+  
+  return
+end subroutine getfc2w