QRA64 decoder is now basically functional with qra64_decode_fastfading(). Currently only submode A. More to come...

git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@7299 ab8295b8-cf94-4d9e-aec4-7959e3be5d79

lib/qra/qra64/qra64_subs.c

@@ -43,6 +43,9 @@ void qra64_dec_(float r[], int* nc1, int* nc2, int* ng2, int* APtype,
   static int nc1z=-1;
   float EbNodBEstimated;
   int err=0;
+  int nSubmode=0;
+  int nFadingModel=1;
+  float b90=1.0;
 
 #ifdef NICO_WANTS_SNR_DUMP  
   FILE *fout;
@@ -53,7 +56,9 @@ void qra64_dec_(float r[], int* nc1, int* nc2, int* ng2, int* APtype,
   if(err<0) printf("ERROR: qra64_apset returned %d\n",err);
 
   if(*iset==0) {
-    *rc = qra64_decode(pqra64codec,&EbNodBEstimated,xdec,r);
+    //    *rc = qra64_decode(pqra64codec,&EbNodBEstimated,xdec,r);
+    *rc = qra64_decode_fastfading(pqra64codec,&EbNodBEstimated,xdec,r,
+				  nSubmode,b90,nFadingModel);
     *snr = EbNodBEstimated - 31.0;
 
 #ifdef NICO_WANTS_SNR_DUMP  

lib/qra64a.f90

@@ -2,7 +2,7 @@ subroutine qra64a(dd,nutc,nf1,nf2,nfqso,ntol,mode64,mycall_12,hiscall_12,   &
      hisgrid_6,sync,nsnr,dtx,nfreq,decoded,nft)
 
   use packjt
-  parameter (NFFT=2*6912,NZ=5760,NMAX=60*12000)
+  parameter (NFFT=2*6912,NZ=5760,NMAX=60*12000,LN=1152*63)
   character decoded*22
   character*12 mycall_12,hiscall_12
   character*6 mycall,hiscall,hisgrid_6
@@ -13,7 +13,7 @@ subroutine qra64a(dd,nutc,nf1,nf2,nfqso,ntol,mode64,mycall_12,hiscall_12,   &
 !  integer*8 count0,count1,clkfreq
   real a(3)
   real dd(NMAX)                              !Raw data sampled at 12000 Hz
-  real s3(0:63,1:63)                         !Symbol spectra
+  real s3(LN)                                !Symbol spectra
   integer dat4(12)                           !Decoded message (as 12 integers)
   data nc1z/-1/,nc2z/-1/,ng2z/-1/
   save
@@ -41,6 +41,8 @@ subroutine qra64a(dd,nutc,nf1,nf2,nfqso,ntol,mode64,mycall_12,hiscall_12,   &
   
   npts2=216000
   naptype=4
+  LL=64*(mode64+2)
+  NN=63
   do itry0=1,3
      idf0=itry0/2
      if(mod(itry0,2).eq.0) idf0=-idf0
@@ -52,7 +54,7 @@ subroutine qra64a(dd,nutc,nf1,nf2,nfqso,ntol,mode64,mycall_12,hiscall_12,   &
         if(mod(itry1,2).eq.0) idf1=-idf1
         a(2)=-0.67*(idf1 + 0.67*kpk)
         call twkfreq(c00,c0,npts2,4000.0,a)
-        call spec64(c0,npts2,mode64,jpk,s3)
+        call spec64(c0,npts2,mode64,jpk,s3,LL,NN)
         call qra64_dec(s3,nc1,nc2,ng2,naptype,0,dat4,snr2,irc)
         decoded='                      '
         if(irc.ge.0) then

lib/spec64.f90

@@ -1,42 +1,24 @@
-subroutine spec64(c0,npts2,mode64,jpk,s3a)
+subroutine spec64(c0,npts2,mode64,jpk,s3,LL,NN)
 
   parameter (NSPS=2304)                      !Samples per symbol at 4000 Hz
   complex c0(0:360000)                       !Complex spectrum of dd()
   complex cs(0:NSPS-1)                       !Complex symbol spectrum
-  real s3a(0:63,1:63)                        !Synchronized symbol spectra
+  real s3(LL,NN)                             !Synchronized symbol spectra
 
-  nfft4=221184
+  nfft6=nsps
-  c0(npts2:)=0.
+  fsample=4000.0
-  call four2a(c0,nfft4,1,-1,1)             !Forward c2c
-  ndown=16/mode64
-  nfft5=nfft4/ndown
-  npts3=npts2/ndown
-  call four2a(c0,nfft5,1,1,1)              !Inverse c2c, downsampled
-
-  nfft6=nsps/ndown
-  fsample=4000.0/ndown
   df=fsample/nfft6
-  jpkd=nint(float(jpk)/ndown)
   do j=1,63
-     jj=j+7                                !Skip first Costas array
+     jj=j+7                                  !Skip first Costas array
-     if(j.ge.32) jj=j+14                   !Skip middle Costas array
+     if(j.ge.32) jj=j+14                     !Skip middle Costas array
-     ja=jpkd + (jj-1)*nfft6
+     ja=jpk + (jj-1)*nfft6
      jb=ja+nfft6-1
      cs(0:nfft6-1)=1.3e-8*c0(ja:jb)
      call four2a(cs,nfft6,1,-1,1)
-     ia=-mode64/2 - mode64
+     do ii=1,LL
-     do ii=0,63
+        i=ii-65
-        ia=ia+mode64
+        if(i.lt.0) i=i+nfft6
-        ib=ia+mode64-1
+        s3(ii,j)=real(cs(i))**2 + aimag(cs(i))**2
-        s=0.
-        do i=ia,ib
-           if(i.ge.0) then
-              s=s + real(cs(i))**2 + aimag(cs(i))**2
-           else
-              s=s + real(cs(nfft6+i))**2 + aimag(cs(nfft6+i))**2
-           endif
-        enddo
-        s3a(ii,j)=s/mode64
      enddo
   enddo