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688 lines
18 KiB
Fortran
688 lines
18 KiB
Fortran
module q65
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parameter (NSTEP=8) !Number of time bins per symbol in s1, s1a, s1b
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parameter (PLOG_MIN=-242.0) !List decoding threshold
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integer nsave,nlist,LL0,iz0,jz0
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integer listutc(10)
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integer apsym0(58),aph10(10)
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integer apmask1(78),apsymbols1(78)
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integer apmask(13),apsymbols(13)
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integer,dimension(22) :: isync = (/1,9,12,13,15,22,23,26,27,33,35, &
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38,46,50,55,60,62,66,69,74,76,85/)
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integer codewords(63,206)
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integer ibwa,ibwb,ncw,nsps,mode_q65,nfa,nfb
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integer idf,idt,ibw,ndist,maxiters
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integer istep,nsmo,lag1,lag2,npasses,nused,iseq,ncand,nrc
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integer i0,j0
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integer navg(0:1)
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logical lnewdat
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real candidates(20,3) !snr, xdt, and f0 of top candidates
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real, allocatable :: s1raw(:,:) !Symbol spectra, 1/8-symbol steps
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real, allocatable :: s1(:,:) !Symbol spectra w/suppressed peaks
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real, allocatable,save :: s1a(:,:,:) !Cumulative symbol spectra
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real sync(85) !sync vector
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real df,dtstep,dtdec,f0dec,ftol
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contains
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subroutine q65_dec0(iavg,nutc,iwave,ntrperiod,nfqso,ntol,ndepth,lclearave, &
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emedelay,xdt,f0,snr1,width,dat4,snr2,idec)
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! Top-level routine in q65 module
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! - Compute symbol spectra
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! - Attempt sync and q3 decode using all 85 symbols
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! - If that fails, try sync with 22 symbols and standard q[0124] decode
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! Input: iavg 0 for single-period decode, 1 for average
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! iwave(0:nmax-1) Raw data
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! ntrperiod T/R sequence length (s)
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! nfqso Target frequency (Hz)
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! ntol Search range around nfqso (Hz)
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! ndepth Requested decoding depth
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! lclearave Flag to clear the accumulating array
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! emedelay Extra delay for EME signals
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! Output: xdt Time offset from nominal (s)
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! f0 Frequency of sync tone
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! snr1 Relative SNR of sync signal
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! width Estimated Doppler spread
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! dat4(13) Decoded message as 13 six-bit integers
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! snr2 Estimated SNR of decoded signal
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! idec Flag for decoding results
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! -1 No decode
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! 0 No AP
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! 1 "CQ ? ?"
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! 2 "Mycall ? ?"
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! 3 "MyCall HisCall ?"
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use packjt77
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use timer_module, only: timer
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parameter (LN=2176*63) !LN=LL*NN; LL=64*(mode_q65+2), NN=63
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integer*2 iwave(0:12000*ntrperiod-1) !Raw data
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integer dat4(13)
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character*37 decoded
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logical first,lclearave
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real, allocatable :: s3(:,:) !Data-symbol energies s3(LL,63)
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real, allocatable :: ccf1(:) !CCF(freq) at fixed lag (red)
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real, allocatable :: ccf2(:) !Max CCF(freq) at any lag (orange)
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data first/.true./
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save first
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if(nutc+ndepth.eq.-999) stop !Silence compiler warnings
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! Set some parameters and allocate storage for large arrays
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irc=-2
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nrc=-2
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idec=-1
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snr1=0.
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dat4=0
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LL=64*(2+mode_q65)
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nfft=nsps
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df=12000.0/nfft !Freq resolution = baud
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istep=nsps/NSTEP
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iz=5000.0/df !Uppermost frequency bin, at 5000 Hz
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txt=85.0*nsps/12000.0
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jz=(txt+1.0)*12000.0/istep !Number of symbol/NSTEP bins
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if(nsps.ge.6912) jz=(txt+2.0)*12000.0/istep !For TR 60 s and higher
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ftol=ntol
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ia=ntol/df
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ia2=max(ia,10*mode_q65,nint(100.0/df))
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nsmo=int(0.7*mode_q65*mode_q65)
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if(nsmo.lt.1) nsmo=1
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if(first) then !Generate the sync vector
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sync=-22.0/63.0 !Sync tone OFF
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do k=1,22
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sync(isync(k))=1.0 !Sync tone ON
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enddo
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endif
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allocate(s3(-64:LL-65,63))
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allocate(ccf1(-ia2:ia2))
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allocate(ccf2(iz))
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if(LL.ne.LL0 .or. iz.ne.iz0 .or. jz.ne.jz0 .or. lclearave) then
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if(allocated(s1raw)) deallocate(s1raw)
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allocate(s1raw(iz,jz))
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if(allocated(s1)) deallocate(s1)
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allocate(s1(iz,jz))
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if(allocated(s1a)) deallocate(s1a)
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allocate(s1a(iz,jz,0:1))
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s1=0.
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s1a=0.
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navg=0
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LL0=LL
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iz0=iz
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jz0=jz
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lclearave=.false.
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endif
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dtstep=nsps/(NSTEP*12000.0) !Step size in seconds
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lag1=-1.0/dtstep
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lag2=1.0/dtstep + 0.9999
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if(nsps.ge.3600 .and. emedelay.gt.0) lag2=4.0/dtstep + 0.9999 !Include EME
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j0=0.5/dtstep
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if(nsps.ge.7200) j0=1.0/dtstep !Nominal start-signal index
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s3=0.
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if(iavg.eq.0) then
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call timer('q65_syms',0)
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! Compute symbol spectra with NSTEP time bins per symbol
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call q65_symspec(iwave,ntrperiod*12000,iz,jz,s1)
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call timer('q65_syms',1)
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else
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s1=s1a(:,:,iseq)
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endif
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i0=nint(nfqso/df) !Target QSO frequency
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if(i0-64.lt.1 .or. i0-65+LL.gt.iz) go to 900 !Frequency out of range
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call pctile(s1(i0-64:i0-65+LL,1:jz),LL*jz,45,base)
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s1=s1/base
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s1raw=s1
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! Apply fast AGC to the symbol spectra
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s1max=20.0 !Empirical choice
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do j=1,jz !### Maybe wrong way? ###
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smax=maxval(s1(i0-64:i0-65+LL,j))
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if(smax.gt.s1max) s1(i0-64:i0-65+LL,j)=s1(i0-64:i0-65+LL,j)*s1max/smax
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enddo
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dat4=0
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if(ncw.gt.0 .and. iavg.lt.2) then
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! Try list decoding via "Deep Likelihood".
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call timer('ccf_85 ',0)
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! Try to synchronize using all 85 symbols
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call q65_ccf_85(s1,iz,jz,nfqso,ia,ia2,ipk,jpk,f0,xdt,imsg_best,ccf1)
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call timer('ccf_85 ',1)
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call timer('list_dec',0)
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call q65_dec_q3(s1,iz,jz,s3,LL,ipk,jpk,snr2,dat4,idec,decoded)
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call timer('list_dec',1)
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endif
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! Get 2d CCF and ccf2 using sync symbols only
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call q65_ccf_22(s1,iz,jz,nfqso,ipk,jpk,f0a,xdta,ccf2)
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if(idec.lt.0) then
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f0=f0a
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xdt=xdta
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endif
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! Estimate rms on ccf2 baseline
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call q65_sync_curve(ccf2,1,iz,rms2)
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smax=maxval(ccf2)
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snr1=0.
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if(rms2.gt.0) snr1=smax/rms2
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if(idec.le.0) then
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! The q3 decode attempt failed. Copy synchronized symbol energies from s1
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! into s3 and prepare to try a more general decode.
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call q65_s1_to_s3(s1,iz,jz,ipk,jpk,LL,mode_q65,sync,s3)
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endif
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smax=maxval(ccf1)
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! Estimate frequenct spread
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i1=-9999
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i2=-9999
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do i=-ia,ia
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if(i1.eq.-9999 .and. ccf1(i).ge.0.5*smax) i1=i
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if(i2.eq.-9999 .and. ccf1(-i).ge.0.5*smax) i2=-i
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enddo
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width=df*(i2-i1)
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if(ncw.eq.0) ccf1=0.
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call q65_write_red(iz,ia2,xdt,ccf1,ccf2)
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if(iavg.eq.2) then
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call q65_dec_q012(s3,LL,snr2,dat4,idec,decoded)
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endif
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900 return
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end subroutine q65_dec0
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subroutine q65_clravg
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! Clear the averaging array to start a new average.
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if(allocated(s1a)) s1a(:,:,iseq)=0.
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navg(iseq)=0
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return
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end subroutine q65_clravg
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subroutine q65_symspec(iwave,nmax,iz,jz,s1)
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! Compute symbol spectra with NSTEP time-steps per symbol.
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integer*2 iwave(0:nmax-1) !Raw data
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real s1(iz,jz)
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complex, allocatable :: c0(:) !Complex spectrum of symbol
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allocate(c0(0:nsps-1))
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nfft=nsps
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fac=1/32767.0
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do j=1,jz !Compute symbol spectra at step size
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i1=(j-1)*istep
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i2=i1+nsps-1
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k=-1
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do i=i1,i2,2 !Load iwave data into complex array c0, for r2c FFT
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xx=iwave(i)
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yy=iwave(i+1)
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k=k+1
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c0(k)=fac*cmplx(xx,yy)
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enddo
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c0(k+1:)=0.
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call four2a(c0,nfft,1,-1,0) !r2c FFT
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do i=1,iz
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s1(i,j)=real(c0(i))**2 + aimag(c0(i))**2
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enddo
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! For large Doppler spreads, should we smooth the spectra here?
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if(nsmo.le.1) nsmo=0
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do i=1,nsmo
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call smo121(s1(1:iz,j),iz)
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enddo
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enddo
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if(lnewdat) then
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navg(iseq)=navg(iseq) + 1
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ntc=min(navg(iseq),4) !Averaging time constant in sequences
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u=1.0/ntc
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s1a(:,:,iseq)=u*s1 + (1.0-u)*s1a(:,:,iseq)
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endif
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return
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end subroutine q65_symspec
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subroutine q65_dec_q3(s1,iz,jz,s3,LL,ipk,jpk,snr2,dat4,idec,decoded)
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! Copy synchronized symbol energies from s1 into s3, then attempt a q3 decode.
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character*37 decoded
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integer dat4(13)
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real s1(iz,jz)
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real s3(-64:LL-65,63)
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call q65_s1_to_s3(s1,iz,jz,ipk,jpk,LL,mode_q65,sync,s3)
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nsubmode=0
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if(mode_q65.eq.2) nsubmode=1
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if(mode_q65.eq.4) nsubmode=2
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if(mode_q65.eq.8) nsubmode=3
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if(mode_q65.eq.16) nsubmode=4
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if(mode_q65.eq.32) nsubmode=5
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baud=12000.0/nsps
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do ibw=ibwa,ibwb
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b90=1.72**ibw
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b90ts=b90/baud
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call q65_dec1(s3,nsubmode,b90ts,esnodb,irc,dat4,decoded)
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nrc=irc
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if(irc.ge.0) then
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snr2=esnodb - db(2500.0/baud) + 3.0 !Empirical adjustment
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idec=3
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exit
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endif
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enddo
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return
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end subroutine q65_dec_q3
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subroutine q65_dec_q012(s3,LL,snr2,dat4,idec,decoded)
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! Do separate passes attempting q0, q1, q2 decodes.
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character*37 decoded
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character*78 c78
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integer dat4(13)
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real s3(-64:LL-65,63)
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logical lapcqonly
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nsubmode=0
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if(mode_q65.eq.2) nsubmode=1
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if(mode_q65.eq.4) nsubmode=2
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if(mode_q65.eq.8) nsubmode=3
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if(mode_q65.eq.16) nsubmode=4
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baud=12000.0/nsps
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iaptype=0
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nQSOprogress=0 !### TEMPORARY ? ###
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ncontest=0
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lapcqonly=.false.
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do ipass=0,npasses !Loop over AP passes
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apmask=0 !Try first with no AP information
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apsymbols=0
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if(ipass.ge.1) then
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! Subsequent passes use AP information appropiate for nQSOprogress
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call q65_ap(nQSOprogress,ipass,ncontest,lapcqonly,iaptype, &
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apsym0,apmask1,apsymbols1)
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write(c78,1050) apmask1
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1050 format(78i1)
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read(c78,1060) apmask
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1060 format(13b6.6)
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write(c78,1050) apsymbols1
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read(c78,1060) apsymbols
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endif
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do ibw=ibwa,ibwb
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b90=1.72**ibw
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b90ts=b90/baud
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call q65_dec2(s3,nsubmode,b90ts,esnodb,irc,dat4,decoded)
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nrc=irc
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if(irc.ge.0) then
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snr2=esnodb - db(2500.0/baud) + 3.0 !Empirical adjustment
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idec=iaptype
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go to 100
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endif
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enddo
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enddo
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100 return
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end subroutine q65_dec_q012
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subroutine q65_ccf_85(s1,iz,jz,nfqso,ia,ia2,ipk,jpk,f0,xdt,imsg_best,ccf1)
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! Attempt synchronization using all 85 symbols, in advance of an
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! attempt at q3 decoding. Return ccf1 for the "red sync curve".
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real s1(iz,jz)
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real, allocatable :: ccf(:,:) !CCF(freq,lag)
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real ccf1(-ia2:ia2)
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integer ijpk(2)
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integer itone(85)
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allocate(ccf(-ia2:ia2,-53:214))
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ipk=0
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jpk=0
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ccf_best=0.
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imsg_best=-1
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do imsg=1,ncw
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i=1
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k=0
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do j=1,85
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if(j.eq.isync(i)) then
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i=i+1
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itone(j)=0
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else
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k=k+1
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itone(j)=codewords(k,imsg) + 1
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endif
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enddo
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! Compute 2D ccf using all 85 symbols in the list message
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ccf=0.
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iia=200.0/df
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do lag=lag1,lag2
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do k=1,85
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j=j0 + NSTEP*(k-1) + 1 + lag
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if(j.ge.1 .and. j.le.jz) then
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do i=-ia2,ia2
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ii=i0+mode_q65*itone(k)+i
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if(ii.ge.iia .and. ii.le.iz) ccf(i,lag)=ccf(i,lag) + s1(ii,j)
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enddo
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endif
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enddo
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enddo
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ccfmax=maxval(ccf(-ia:ia,:))
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if(ccfmax.gt.ccf_best) then
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ccf_best=ccfmax
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ijpk=maxloc(ccf(-ia:ia,:))
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ipk=ijpk(1)-ia-1
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jpk=ijpk(2)-53-1
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f0=nfqso + ipk*df
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xdt=jpk*dtstep
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imsg_best=imsg
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ccf1=ccf(:,jpk)
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endif
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enddo ! imsg
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deallocate(ccf)
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return
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end subroutine q65_ccf_85
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subroutine q65_ccf_22(s1,iz,jz,nfqso,ipk,jpk,f0,xdt,ccf2)
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! Attempt synchronization using only the 22 sync symbols. Return ccf2
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! for the "orange sync curve".
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real s1(iz,jz)
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real ccf2(iz) !Orange sync curve
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real, allocatable :: xdt2(:)
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integer, allocatable :: indx(:)
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allocate(xdt2(iz))
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allocate(indx(iz))
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ccfbest=0.
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ibest=0
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lagpk=0
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lagbest=0
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do i=1,iz
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ccfmax=0.
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do lag=lag1,lag2
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ccft=0.
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do k=1,85
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n=NSTEP*(k-1) + 1
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j=n+lag+j0
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if(j.ge.1 .and. j.le.jz) then
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ccft=ccft + sync(k)*s1(i,j)
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endif
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enddo
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if(ccft.gt.ccfmax) then
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ccfmax=ccft
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lagpk=lag
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endif
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enddo
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ccf2(i)=ccfmax
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xdt2(i)=lagpk*dtstep
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if(ccfmax.gt.ccfbest .and. abs(i*df-nfqso).le.ftol) then
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ccfbest=ccfmax
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ibest=i
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lagbest=lagpk
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endif
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enddo
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! Parameters for the top candidate:
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ipk=ibest - i0
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jpk=lagbest
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f0=nfqso + ipk*df
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xdt=jpk*dtstep
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! Save parameters for best candidates
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i1=max(nfa,100)/df
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i2=min(nfb,4900)/df
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jzz=i2-i1+1
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call pctile(ccf2(i1:i2),jzz,40,base)
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ccf2=ccf2/base
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call indexx(ccf2(i1:i2),jzz,indx)
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ncand=0
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maxcand=20
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do j=1,20
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i=indx(jzz-j+1)+i1-1
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if(ccf2(i).lt.3.4) exit !Candidate limit
|
|
f=i*df
|
|
if(f.ge.(nfqso-ftol) .and. f.le.(nfqso+ftol)) cycle
|
|
i3=max(1,i-67*mode_q65)
|
|
i4=min(iz,i+3*mode_q65)
|
|
biggest=maxval(ccf2(i3:i4))
|
|
if(ccf2(i).ne.biggest) cycle
|
|
ncand=ncand+1
|
|
candidates(ncand,1)=ccf2(i)
|
|
candidates(ncand,2)=xdt2(i)
|
|
candidates(ncand,3)=f
|
|
if(ncand.ge.maxcand) exit
|
|
enddo
|
|
|
|
return
|
|
end subroutine q65_ccf_22
|
|
|
|
subroutine q65_dec1(s3,nsubmode,b90ts,esnodb,irc,dat4,decoded)
|
|
|
|
! Attmpt a full-AP list decode.
|
|
|
|
use packjt77
|
|
real s3(1,1) !Silence compiler warning that wants to see a 2D array
|
|
real s3prob(0:63,63) !Symbol-value probabilities
|
|
integer dat4(13)
|
|
character c77*77,decoded*37
|
|
logical unpk77_success
|
|
|
|
nFadingModel=1
|
|
decoded=' '
|
|
call q65_intrinsics_ff(s3,nsubmode,b90ts,nFadingModel,s3prob)
|
|
call q65_dec_fullaplist(s3,s3prob,codewords,ncw,esnodb,dat4,plog,irc)
|
|
if(sum(dat4).le.0) irc=-2
|
|
if(irc.ge.0 .and. plog.gt.PLOG_MIN) then
|
|
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
|
|
else
|
|
irc=-1
|
|
endif
|
|
nrc=irc
|
|
|
|
return
|
|
end subroutine q65_dec1
|
|
|
|
subroutine q65_dec2(s3,nsubmode,b90ts,esnodb,irc,dat4,decoded)
|
|
|
|
! Attempt a q0, q1, or q2 decode using spcified AP information.
|
|
|
|
use packjt77
|
|
real s3(iz0,jz0) !Silence compiler warning that wants to see a 2D array
|
|
real s3prob(0:63,63) !Symbol-value probabilities
|
|
integer dat4(13)
|
|
character c77*77,decoded*37
|
|
logical unpk77_success
|
|
|
|
nFadingModel=1
|
|
decoded=' '
|
|
call q65_intrinsics_ff(s3,nsubmode,b90ts,nFadingModel,s3prob)
|
|
call q65_dec(s3,s3prob,APmask,APsymbols,maxiters,esnodb,dat4,irc)
|
|
if(sum(dat4).le.0) irc=-2
|
|
nrc=irc
|
|
if(irc.ge.0) then
|
|
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
|
|
endif
|
|
|
|
return
|
|
end subroutine q65_dec2
|
|
|
|
subroutine q65_s1_to_s3(s1,iz,jz,ipk,jpk,LL,mode_q65,sync,s3)
|
|
|
|
! Copy synchronized symbol energies from s1 (or s1a) into s3.
|
|
|
|
real s1(iz,jz)
|
|
real s3(-64:LL-65,63)
|
|
real sync(85) !sync vector
|
|
|
|
i1=i0+ipk-64 + mode_q65
|
|
i2=i1+LL-1
|
|
if(i1.ge.1 .and. i2.le.iz) then
|
|
j=j0+jpk-7
|
|
n=0
|
|
do k=1,85
|
|
j=j+8
|
|
if(sync(k).gt.0.0) then
|
|
cycle
|
|
endif
|
|
n=n+1
|
|
if(j.ge.1 .and. j.le.jz) s3(-64:LL-65,n)=s1(i1:i2,j)
|
|
enddo
|
|
endif
|
|
call q65_bzap(s3,LL) !Zap birdies
|
|
|
|
return
|
|
end subroutine q65_s1_to_s3
|
|
|
|
subroutine q65_write_red(iz,ia2,xdt,ccf1,ccf2)
|
|
|
|
! Write data for the red and orange sync curves to LU 17.
|
|
|
|
real ccf1(-ia2:ia2)
|
|
real ccf2(iz)
|
|
|
|
call q65_sync_curve(ccf1,-ia2,ia2,rms1)
|
|
call q65_sync_curve(ccf2,1,iz,rms2)
|
|
|
|
rewind 17
|
|
write(17,1000) xdt
|
|
do i=1,iz
|
|
freq=i*df
|
|
ii=i-i0
|
|
if(freq.ge.float(nfa) .and. freq.le.float(nfb)) then
|
|
ccf1a=-99.0
|
|
if(ii.ge.-ia2 .and. ii.le.ia2) ccf1a=ccf1(ii)
|
|
write(17,1000) freq,ccf1a,ccf2(i)
|
|
1000 format(3f10.3)
|
|
endif
|
|
enddo
|
|
|
|
return
|
|
end subroutine q65_write_red
|
|
|
|
subroutine q65_sync_curve(ccf1,ia,ib,rms1)
|
|
|
|
! Condition the red or orange sync curve for plotting.
|
|
|
|
real ccf1(ia:ib)
|
|
|
|
ic=(ib-ia)/8;
|
|
nsum=2*(ic+1)
|
|
|
|
base1=(sum(ccf1(ia:ia+ic)) + sum(ccf1(ib-ic:ib)))/nsum
|
|
ccf1=ccf1-base1
|
|
sq=dot_product(ccf1(ia:ia+ic),ccf1(ia:ia+ic)) + &
|
|
dot_product(ccf1(ib-ic:ib),ccf1(ib-ic:ib))
|
|
rms1=0.
|
|
if(nsum.gt.0) rms1=sqrt(sq/nsum)
|
|
if(rms1.gt.0.0) ccf1=2.0*ccf1/rms1
|
|
smax1=maxval(ccf1)
|
|
if(smax1.gt.10.0) ccf1=10.0*ccf1/smax1
|
|
|
|
return
|
|
end subroutine q65_sync_curve
|
|
|
|
subroutine q65_bzap(s3,LL)
|
|
|
|
parameter (NBZAP=15)
|
|
real s3(-64:LL-65,63)
|
|
integer ipk1(1)
|
|
integer, allocatable :: hist(:)
|
|
|
|
allocate(hist(-64:LL-65))
|
|
hist=0
|
|
do j=1,63
|
|
ipk1=maxloc(s3(:,j))
|
|
i=ipk1(1) - 65
|
|
hist(i)=hist(i)+1
|
|
enddo
|
|
if(maxval(hist).gt.NBZAP) then
|
|
do i=-64,LL-65
|
|
if(hist(i).gt.NBZAP) s3(i,1:63)=1.0
|
|
enddo
|
|
endif
|
|
|
|
return
|
|
end subroutine q65_bzap
|
|
|
|
subroutine q65_snr(dat4,dtdec,f0dec,mode_q65,snr2)
|
|
|
|
! Estimate SNR of a decoded transmission by aligning the spectra of
|
|
! all 85 symbols.
|
|
|
|
integer dat4(13)
|
|
integer codeword(63)
|
|
integer itone(85)
|
|
real, allocatable :: spec(:)
|
|
|
|
allocate(spec(iz0))
|
|
call q65_enc(dat4,codeword)
|
|
i=1
|
|
k=0
|
|
do j=1,85
|
|
if(j.eq.isync(i)) then
|
|
i=i+1
|
|
itone(j)=0
|
|
else
|
|
k=k+1
|
|
itone(j)=codeword(k) + 1
|
|
endif
|
|
enddo
|
|
|
|
spec=0.
|
|
lagpk=nint(dtdec/dtstep)
|
|
do k=1,85
|
|
j=j0 + NSTEP*(k-1) + 1 + lagpk
|
|
if(j.ge.1 .and. j.le.jz0) then
|
|
do i=1,iz0
|
|
ii=i+mode_q65*itone(k)
|
|
if(ii.ge.1 .and. ii.le.iz0) spec(i)=spec(i) + s1raw(ii,j)
|
|
enddo
|
|
endif
|
|
enddo
|
|
|
|
i0=nint(f0dec/df)
|
|
nsum=max(10*mode_q65,nint(50.0/df))
|
|
ia=i0 - 2*nsum
|
|
ib=i0 + 2*nsum
|
|
sum1=sum(spec(ia:ia+nsum-1))
|
|
sum2=sum(spec(ib-nsum+1:ib))
|
|
avg=(sum1+sum2)/(2.0*nsum)
|
|
spec=spec/avg !Baseline level is now 1.0
|
|
smax=maxval(spec(ia:ib))
|
|
sig_area=sum(spec(ia+nsum:ib-nsum)-1.0)
|
|
w_equiv=sig_area/(smax-1.0)
|
|
snr2=db(max(1.0,sig_area)) - db(2500.0/df)
|
|
|
|
! do i=ia,ib
|
|
! write(71,3071) i*df,spec(i),db(spec(i))
|
|
!3071 format(3f10.3)
|
|
! enddo
|
|
! flush(71)
|
|
|
|
return
|
|
end subroutine q65_snr
|
|
|
|
end module q65
|