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Remove residual dt error caused by decimation filter and coherent integrator. Also, typos and minor edits on ftrsd paper.

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git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@6387 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
This commit is contained in:
Steven Franke 2016-01-12 03:28:30 +00:00
parent 6c925494ec
commit f78c11010c
2 changed files with 12 additions and 12 deletions
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4
lib/decode65a.f90
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@ -39,7 +39,8 @@ subroutine decode65a(dd,npts,newdat,nqd,f0,nflip,mode65,ntrials, &
dtbest=dt
call afc65b(c5x,n6,fsample,nflip,a,ccfbest,dtbest)
call timer('afc65b ',1)
dtbest=dtbest+0.003628 ! remove decimation filter and coh. integrator delay
dt=dtbest !return new, improved estimate of dt
sync2=3.7e-4*ccfbest/sq0 !Constant is empirical
! Apply AFC corrections to the time-domain signal
@ -79,7 +80,6 @@ subroutine decode65a(dd,npts,newdat,nqd,f0,nflip,mode65,ntrials, &
call timer('dec65b ',0)
call decode65b(s2,nflip,mode65,ntrials,naggressive,ndepth, &
mycall,hiscall,hisgrid,nexp_decode,nqd,nft,qual,nhist,decoded)
dt=dtbest !return new, improved estimate of dt
call timer('dec65b ',1)
return

20
lib/ftrsd/ftrsd_paper/ftrsd.lyx
View File

@ -851,7 +851,7 @@ The FT algorithm uses quality indices made available by a noncoherent 64-FSK
\end_inset
of the symbol's fractional power
\begin_inset Formula $p_{1,\,j}$
\begin_inset Formula $p_{1,\, j}$
\end_inset
in a sorted list of
@ -921,7 +921,7 @@ t educated guesses to select symbols for erasure.
, the soft distance between the received word and the codeword:
\begin_inset Formula
\begin{equation}
d_{s}=\sum_{j=1}^{n}\alpha_{j}\,(1+p_{1,\,j}).\label{eq:soft_distance}
d_{s}=\sum_{j=1}^{n}\alpha_{j}\,(1+p_{1,\, j}).\label{eq:soft_distance}
\end{equation}
\end_inset
@ -939,7 +939,7 @@ Here
\end_inset
if the received symbol and codeword symbol are different, and
\begin_inset Formula $p_{1,\,j}$
\begin_inset Formula $p_{1,\, j}$
\end_inset
is the fractional power associated with received symbol
@ -983,7 +983,7 @@ In practice we find that
\begin_layout Standard
\begin_inset Formula
\begin{equation}
u=\frac{1}{n}\sum_{j=1}^{n}S(c_{j},\,j).\label{eq:u-metric}
u=\frac{1}{n}\sum_{j=1}^{n}S(c_{j},\, j).\label{eq:u-metric}
\end{equation}
\end_inset
@ -1016,7 +1016,7 @@ The correct JT65 codeword produces a value for
bins containing noise only.
Thus, if the spectral array
\begin_inset Formula $S(i,\,j)$
\begin_inset Formula $S(i,\, j)$
\end_inset
has been normalized so that the average value of the noise-only bins is
@ -1265,7 +1265,7 @@ For each received symbol, define the erasure probability as 1.3 times the
a priori
\emph default
symbol-error probability determined from soft-symbol information
\begin_inset Formula $\{p_{1}\textrm{-rank},\,p_{2}/p_{1}\}$
\begin_inset Formula $\{p_{1}\textrm{-rank},\, p_{2}/p_{1}\}$
\end_inset
.
@ -2265,8 +2265,8 @@ ing tones of signals from DL7UAE and SP6GWB.
\begin_inset Formula $-24$
\end_inset
dB, respectrively, just one or two dB above the decoding threshold for
the FT decoder.
dB, respectively, just one or two dB above the decoding threshold for the
FT decoder.
Note that the two signals overlap throughout 94% of their occupied bandwidths,
yet both are decoded cleanly and without errors.
Such behavior is typical of the JT65 protocol.
@ -2301,8 +2301,8 @@ name "fig:JT65B_EME"
Examples of JT65B EME signals recorded at K1JT.
Numbers above the spectrogram are audio frequencies in Hz, and the spectrogram'
s vertical direction is one minute of time.
The horizintal green bar indicates full band occupied by the second decoded
signal, a reply from SP6GWB.
The horizontal green bar on the frequency axis indicates the bandwidth
occupied by the second decoded signal, a reply from SP6GWB.
See text for additional details.
\end_layout