15bf364e5e
commit dbca224ee15f598ba86b860c19e902b594f6b888
Author: Jordan Sherer <jordan@widefido.com>
Date: Wed Aug 14 21:10:17 2019 -0400
Cleanup decoder with easy parameters
commit 427a6ac6bf02a7de80e76b921bbd48ec23dab0c4
Author: Jordan Sherer <jordan@widefido.com>
Date: Tue Aug 13 22:56:32 2019 -0400
Working on downsampling
commit ef5e1fb9cdafb6069b6f67377c3bc9e073d2785e
Author: Jordan Sherer <jordan@widefido.com>
Date: Tue Aug 13 22:01:34 2019 -0400
Fixed NN parameters
commit 216dbc83a931127540fb028d3365a205b4ef1d28
Author: Jordan Sherer <jordan@widefido.com>
Date: Tue Aug 13 21:40:20 2019 -0400
Fixed dupe during sync
commit 9505d50ba6c42b05e5fff1a059864a643d9e7558
Author: Jordan Sherer <jordan@widefido.com>
Date: Tue Aug 13 16:54:37 2019 -0400
Tweaking downsampling
commit 86cd07e1ac8ce8d64cdd2d4321cf295cd867f80e
Author: Jordan Sherer <jordan@widefido.com>
Date: Tue Aug 13 10:11:07 2019 -0400
Working with logging
commit 0de3849a442d20081f545c6fef5fadf2def6e0d2
Author: Jordan Sherer <jordan@widefido.com>
Date: Tue Aug 13 03:46:51 2019 -0400
250 millisecond startup delay
commit a35cc5302b6f8532a424d504a4e2feaacf74ef99
Author: Jordan Sherer <jordan@widefido.com>
Date: Tue Aug 13 03:39:20 2019 -0400
1200 sps, 10 seconds, 80Hz
commit 6f36db20f90c510336b497605d9d7667d6f0f44f
Author: Jordan Sherer <jordan@widefido.com>
Date: Tue Aug 13 03:27:12 2019 -0400
Working word count
commit 741c55ac0840512d68e1fbdb2f1fff6adfcd4612
Author: Jordan Sherer <jordan@widefido.com>
Date: Tue Aug 13 02:40:40 2019 -0400
Updated LDPC simulator
commit ce0992644315402503f44bdae4131bacf2cc3e21
Author: Jordan Sherer <jordan@widefido.com>
Date: Tue Aug 13 02:34:01 2019 -0400
Weird. Apparently symbol stop is the only way to get decodes to work in app...need to figure out why
commit 8b330fbff6574f2ee6d7a471dd93a2cb57b492dd
Author: Jordan Sherer <jordan@widefido.com>
Date: Tue Aug 13 01:50:37 2019 -0400
More parameter fixups (downsampling) and first decode
commit 37c780b45e6579294b5a4692b8e8d0602d9bd8b1
Author: Jordan Sherer <jordan@widefido.com>
Date: Mon Aug 12 23:20:58 2019 -0400
More params fixing
commit bc8547e1e8f55bfb4bce5f95890f3cf6798e36d7
Author: Jordan Sherer <jordan@widefido.com>
Date: Mon Aug 12 22:48:00 2019 -0400
Fixed params in fortran code
commit 10fbf9f4a78c6244e0082a31819ee26aeae39325
Author: Jordan Sherer <jordan@widefido.com>
Date: Mon Aug 12 16:08:32 2019 -0400
Using constants in place of literals in a few places to make it easier to change
64 lines
1.5 KiB
Fortran
64 lines
1.5 KiB
Fortran
subroutine subtractft8(dd,itone,f0,dt)
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! Subtract an ft8 signal
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!
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! Measured signal : dd(t) = a(t)cos(2*pi*f0*t+theta(t))
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! Reference signal : cref(t) = exp( j*(2*pi*f0*t+phi(t)) )
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! Complex amp : cfilt(t) = LPF[ dd(t)*CONJG(cref(t)) ]
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! Subtract : dd(t) = dd(t) - 2*REAL{cref*cfilt}
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use timer_module, only: timer
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include 'ft8_params.f90'
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parameter (NFRAME=NSPS*NN)
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parameter (NFFT=NMAX, NFILT=1400)
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real*4 dd(NMAX), window(-NFILT/2:NFILT/2)
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complex cref,camp,cfilt,cw
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integer itone(NN)
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logical first
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data first/.true./
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common/heap8/cref(NFRAME),camp(NMAX),cfilt(NMAX),cw(NMAX)
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save first
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nstart=dt*12000+1
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call genft8refsig(itone,cref,f0)
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camp=0.
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do i=1,nframe
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id=nstart-1+i
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if(id.ge.1.and.id.le.NMAX) camp(i)=dd(id)*conjg(cref(i))
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enddo
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if(first) then
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! Create and normalize the filter
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pi=4.0*atan(1.0)
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fac=1.0/float(nfft)
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sum=0.0
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do j=-NFILT/2,NFILT/2
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window(j)=cos(pi*j/NFILT)**2
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sum=sum+window(j)
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enddo
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cw=0.
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cw(1:NFILT+1)=window/sum
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cw=cshift(cw,NFILT/2+1)
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call four2a(cw,nfft,1,-1,1)
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cw=cw*fac
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first=.false.
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endif
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cfilt=0.0
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cfilt(1:nframe)=camp(1:nframe)
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call four2a(cfilt,nfft,1,-1,1)
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cfilt(1:nfft)=cfilt(1:nfft)*cw(1:nfft)
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call four2a(cfilt,nfft,1,1,1)
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! Subtract the reconstructed signal
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do i=1,nframe
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j=nstart+i-1
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if(j.ge.1 .and. j.le.NMAX) dd(j)=dd(j)-2*REAL(cfilt(i)*cref(i))
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enddo
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return
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end subroutine subtractft8
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