subroutine q65_loops(c00,npts2,nsps2,nsubmode,ndepth,jpk0, & xdt0,f0,iaptype,xdt1,f1,snr2,dat4,idec) use packjt77 use timer_module, only: timer use q65 parameter (NN=63) parameter (LN=2176*63) !LN=LL*NN; LL=64*(mode_q65+2), NN=63 complex c00(0:npts2-1) !Analytic representation of dd(), 6000 Hz complex ,allocatable :: c0(:) !Ditto, with freq shift character decoded*37 real a(3) !twkfreq params f,f1,f2 real,allocatable :: s3(:) !Symbol spectra integer dat4(13) !Decoded message (as 13 six-bit integers) integer nap(0:11) !AP return codes data nap/0,2,3,2,3,4,2,3,6,4,6,6/ LL=64*(mode_q65+2) allocate(s3(LL*NN)) allocate(c0(0:npts2-1)) idec=-1 ircbest=9999 irc=-99 s3lim=20. baud=6000.0/nsps2 idfmax=3 idtmax=3 ibw0=(ibwa+ibwb)/2 maxdist=5 if(iand(ndepth,3).ge.2) then idfmax=5 idtmax=5 maxdist=10 endif if(iand(ndepth,3).eq.3) maxdist=15 napmin=99 xdt1=xdt0 f1=f0 idfbest=0 idtbest=0 ndistbest=0 do idf=1,idfmax ndf=idf/2 if(mod(idf,2).eq.0) ndf=-ndf a=0. a(1)=-(f0+0.5*baud*ndf) call twkfreq(c00,c0,npts2,6000.0,a) do idt=1,idtmax ndt=idt/2 if(mod(idt,2).eq.0) ndt=-ndt jpk=jpk0 + nsps2*ndt/16 !tsym/16 if(jpk.lt.0) jpk=0 call timer('spec64 ',0) call spec64(c0,nsps2,mode_q65,jpk,s3,LL,NN) call timer('spec64 ',1) call pctile(s3,LL*NN,40,base) s3=s3/base where(s3(1:LL*NN)>s3lim) s3(1:LL*NN)=s3lim call q65_bzap(s3,LL) !Zap birdies do ibw=ibwa,ibwb ndist=ndf**2 + ndt**2 + (ibw-ibw0)**2 if(ndist.gt.maxdist) cycle b90=1.72**ibw if(b90.gt.345.0) cycle b90ts = b90/baud call timer('dec2 ',0) call q65_dec2(s3,nsubmode,b90ts,esnodb,irc,dat4,decoded) call timer('dec2 ',1) ! irc > 0 ==> number of iterations required to decode ! -1 = invalid params ! -2 = decode failed ! -3 = CRC mismatch if(irc.ge.0) then idfbest=idf idtbest=idt ndistbest=ndist nrc=irc go to 100 endif enddo ! ibw (b90 loop) enddo ! idt (DT loop) enddo ! idf (f0 loop) 100 if(irc.ge.0) then idec=iaptype snr2=esnodb - db(2500.0/baud) xdt1=xdt0 + nsps2*ndt/(16.0*6000.0) f1=f0 + 0.5*baud*ndf endif return end subroutine q65_loops