2012-07-17 15:31:01 -04:00
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subroutine decodemsk(cdat,npts,cw,i1,nchar,s2,msg)
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! DF snd sync have been established, now decode the message
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complex cdat(npts)
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complex cw(168,0:63) !Complex waveforms for codewords
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real s2(0:63,400)
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character msg*400
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complex z,zmax
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character cc*64
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! 1 2 3 4 5 6
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! 0123456789012345678901234567890123456789012345678901234567890123
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data cc/'0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ./?- _ @'/
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msg=' '
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do j=1,nchar !Find best match for each character
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ia=i1 + (j-1)*168
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smax=0.
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do k=0,40
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kk=k
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2012-07-18 16:13:58 -04:00
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if(k.eq.40) kk=44
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2012-07-17 15:31:01 -04:00
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z=0.
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do i=1,168
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z=z + cdat(ia+i)*conjg(cw(i,kk))
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enddo
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ss=abs(z)
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s2(k,j)=ss
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if(ss.gt.smax) then
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smax=ss
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zmax=z
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kpk=kk
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endif
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enddo
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msg(j:j)=cc(kpk+1:kpk+1)
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2012-07-18 16:13:58 -04:00
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if(kpk.eq.44) msg(j:j)=' '
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2012-07-17 15:31:01 -04:00
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enddo
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return
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end subroutine decodemsk
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