From bb08150e4bb61f4bfa14cbd80c56d6ab10476a9c Mon Sep 17 00:00:00 2001
From: Nico Palermo/IV3NWV <nicopal@microtelecom.it>
Date: Fri, 4 Dec 2020 09:43:41 +0100
Subject: [PATCH] Threshold in q65_sync.f90 increased to -250 only for reports.
 Assumes that the list is in the order defined in q65_set_list.f90 (reports
 are at indexes 5..56). Beware if q65_set_list is changed!!!

---
 lib/q65_decode.f90 |   5 +++
 lib/q65_sync.f90   | 103 +++++++++++++++++++++++++++++++++++++++++++--
 2 files changed, 104 insertions(+), 4 deletions(-)

diff --git a/lib/q65_decode.f90 b/lib/q65_decode.f90
index 0473b7119..e52870b61 100644
--- a/lib/q65_decode.f90
+++ b/lib/q65_decode.f90
@@ -102,6 +102,11 @@ contains
        go to 100
     endif
     
+	! Nico's trick to speed up data analysis
+	! with fullaplist decoding
+	! Uncomment to check only fullaplist synch and decode
+	! snr1 = 1 ! skip non fullaplist decoding attempts
+	
     if(snr1.lt.2.8) go to 100
     jpk0=(xdt+1.0)*6000                      !### Is this OK?
     if(ntrperiod.le.30) jpk0=(xdt+0.5)*6000  !###
diff --git a/lib/q65_sync.f90 b/lib/q65_sync.f90
index aa238d69d..710a35c5b 100644
--- a/lib/q65_sync.f90
+++ b/lib/q65_sync.f90
@@ -27,6 +27,12 @@ subroutine q65_sync(nutc,iwave,nmax,mode_q65,codewords,ncw,nsps,nfqso,ntol,    &
   real, allocatable :: s1(:,:)           !Symbol spectra, 1/8-symbol steps
   real, allocatable :: s3(:,:)           !Data-symbol energies s3(LL,63)
   real, allocatable :: ccf(:,:)          !CCF(freq,lag)
+  
+  ! real, allocatable :: ccfcw(:)        ! Method 2
+  ! real, allocatable :: ccfpk(:)        ! Method 2
+  ! integer cwpk(1)                      ! Method 2
+  ! integer, allocatable :: cwtone(:,:)  ! Method 2
+  
   real, allocatable :: ccf1(:)           !CCF(freq) at best lag
   real s3prob(0:63,63)                   !Symbol-value probabilities
   real sync(85)                          !sync vector
@@ -52,6 +58,10 @@ subroutine q65_sync(nutc,iwave,nmax,mode_q65,codewords,ncw,nsps,nfqso,ntol,    &
   allocate(c0(0:nfft-1))
   allocate(ccf(-ia:ia,-53:214))
   allocate(ccf1(-ia:ia))
+  
+  ! allocate(ccfcw(1:ncw))               ! Method 2
+  ! allocate(ccfpk(1:ncw))               ! Method 2
+  ! allocate(cwtone(ncw,85))             ! Method 2
 
   if(sync(1).eq.99.0) then               !Generate the sync vector
      sync=-22.0/63.0                     !Sync tone OFF  
@@ -106,6 +116,7 @@ subroutine q65_sync(nutc,iwave,nmax,mode_q65,codewords,ncw,nsps,nfqso,ntol,    &
 !######################################################################
 ! Try list decoding via "Deep Likelihood".
 
+! Joe's method
   ipk=0
   jpk=0
   ccf_best=0.
@@ -147,6 +158,66 @@ subroutine q65_sync(nutc,iwave,nmax,mode_q65,codewords,ncw,nsps,nfqso,ntol,    &
      endif
   enddo  ! imsg
 
+! Nico's Method 2
+! Computes the ccf in a different order so that
+! we can see what the ccfs of the list looked like
+! on ccfmax
+
+! Compute codeword tones
+! cwtone = 0
+! do imsg=1,ncw
+!     i=1
+!     k=0
+!     do j=1,85
+!        if(j.eq.isync(i)) then
+!           i=i+1
+!           cwtone(imsg,j)=-1
+!        else
+!           k=k+1
+!           cwtone(imsg,j)=codewords(k,imsg)
+!        endif
+!     enddo
+! enddo
+
+! ipk=0
+! jpk=0
+! ccf_best=0.
+! imsg_best=-1
+! ccf=0.
+! do lag=lag1,lag2
+!    do i=-ia,ia
+!		ccfcw = 0.
+!        do k=1,85
+!            j=j0 + NSTEP*(k-1) + 1 + lag
+!            if(j.ge.1 .and. j.le.jz) then
+!				do imsg=1,ncw
+!				    ! if we would like to check only non systematic symbols
+!					! uncomment the following if
+!					!if (k.gt.18 .or. cwtone(imsg,k).eq.-1) then
+!						ii=i0+mode_q65*cwtone(imsg,k)+i
+!						ccfcw(imsg)=ccfcw(imsg) + s1(ii,j)
+!					!endif
+!			    enddo
+!			endif
+!		enddo
+!		ccfmax=maxval(ccfcw)
+!		ccf(i,lag) = ccfmax
+!       if(ccfmax.gt.ccf_best) then
+!		    ccfpk = ccfcw
+!			cwpk = maxloc(ccfpk)
+!			imsg_best = cwpk(1)
+!			ccf_best = ccfmax
+!		endif
+!	enddo
+! enddo
+! ccfmax=maxval(ccf)
+! ccf_best=ccfmax
+! ijpk=maxloc(ccf)
+! ipk=ijpk(1)-ia-1
+! jpk=ijpk(2)-53-1     
+! f0=nfqso + ipk*df
+! xdt=jpk*dtstep
+  
   ia=i0+ipk-64
   ib=ia+LL-1
   j=j0+jpk-7
@@ -167,22 +238,46 @@ subroutine q65_sync(nutc,iwave,nmax,mode_q65,codewords,ncw,nsps,nfqso,ntol,    &
   if(mode_q65.eq.16) nsubmode=4
   nFadingModel=1
   baud=12000.0/nsps
+  isreport = 0;
   do ibw=2,4
      b90=1.72**ibw
      call q65_intrinsics_ff(s3,nsubmode,b90/baud,nFadingModel,s3prob)
      call q65_dec_fullaplist(s3,s3prob,codewords,ncw,esnodb,dat4,plog,irc)
-     if(irc.ge.0 .and. plog.ge.-255.0) then
+!    Joe's threshold	 
+!     if(irc.ge.0 .and. plog.ge.-255.0) then
+!    Nico's threshold
+	 if (irc.ge.0) then
+	   ! if it is an RRR type or a CQ Mycall grid
+	   ! we accept the fullaplist threshold
+	   ! other cases in the list are reports which
+	   ! are more frequent in the list and then 
+	   ! must be filtered with a higher threshold
+	   if((irc.le.3.0 .or. irc.eq.56.0) .or. plog.ge.-250.0) then
         snr2=esnodb - db(2500.0/baud)
         id1=1
         write(c77,1000) dat4(1:12),dat4(13)/2
 1000    format(12b6.6,b5.5)
         call unpack77(c77,0,decoded,unpk77_success) !Unpack to get msgsent
         open(55,file='fort.55',status='unknown',position='append')
-        write(55,3055) nutc,ibw,xdt,f0,85.0*base,ccfmax,snr2,plog,   &
-             irc,trim(decoded)
-3055    format(i6,i3,6f8.2,i5,2x,a)
+		
+! Joe's dump		
+!        write(55,3055) nutc,ibw,xdt,f0,85.0*base,ccfmax,snr2,plog,   &
+!             irc,trim(decoded)
+!3055    format(i6,i3,6f8.2,i5,2x,a)
+
+! Nico's dump for Method 2
+!       This are the ccfs of the codeword in the list at the
+!       ccf peak
+!       write(55,3083) ccfpk
+!3083	format(10f6.1)
+!       Show also the imsg_best in order to compare it with
+!       irc. (Interestingly they are always equal!)
+!       write(55,3055) nutc,ibw,xdt,f0,85.0*base,ccfmax,snr2,plog,   &
+!             irc,(imsg_best-1),trim(decoded)
+!3055    format(i6,i3,6f8.2,2i5,2x,a)
         close(55)
         go to 900
+	   endif
      endif
   enddo