Move the sweep generator into a separate routine.

lib/superfox/sfox_clo.f90

@@ -3,24 +3,35 @@ subroutine sfox_clo(fsample,syncwidth,clo)
 ! Generate complex LO for the SuperFox sync signal
   
   use sfox_mod
-  complex clo(NMAX)                      !Complex Local Oscillator
+  complex clo(NSYNC)                      !Complex Local Oscillator
+  complex w
+
+  w=1.0
+  call sweep(1500.0,syncwidth,fsample,w,clo,nsync)
+  clo=conjg(clo)
+
+  return
+end subroutine sfox_clo
+
+subroutine sweep(f0,syncwidth,fsample,w,c,iz)
+
+  complex c(iz)
   complex w,wstep
 
   twopi=8.0*atan(1.0)
-  tsync=NS*NSPS/fsample
-  w=1.0
-  a0=1500.0+ syncwidth/2.0          !Frequency at midpoint of LO waveform
-  a2=2.0*syncwidth/tsync            !Frequency drift rate
-  x0=0.5*(nsync+1)
-  s=2.0/nsync
-  do i=1,nsync
-     if(i.eq.nsync/2+1) a2=-a2       !Reverse sign of drift at midpoint
+  ttot=iz/fsample
+  a0=f0 + syncwidth/2.0             !Frequency at midpoint of LO waveform
+  a2=2.0*syncwidth/ttot             !Frequency drift rate
+  x0=0.5*(iz+1)
+  s=2.0/iz
+  do i=1,iz
+     if(i.eq.iz/2+1) a2=-a2         !Reverse sign of drift at midpoint
      x=s*(i-x0)
      dphi=(a0 + x*a2)*(twopi/fsample)
      wstep=cmplx(cos(dphi),sin(dphi))
      w=w*wstep
-     clo(i)=conjg(w)
+     c(i)=w
   enddo
 
   return
-end subroutine sfox_clo
+end subroutine sweep

lib/superfox/sfoxtest.f90

@@ -215,7 +215,6 @@ program sfoxtest
         ntot=ntot+nharderr
         nworst=max(nworst,nharderr)
 
-!        call rs_decode_sf(rxdat,iera,nera,nfixed)    !Call the BM decoder
         ntrials=1000
         call timer('ftrsd3  ',0)
         call ftrsd3(s3,chansym0,rxdat,rxprob,rxdat2,rxprob2,ntrials,  &