Moved all citations to the respective slides

This commit is contained in:
Andreas Tsouchlos 2023-04-19 22:53:45 +02:00
parent 894d80ca90
commit a9bbbd4978
7 changed files with 344 additions and 204 deletions

View File

@ -300,12 +300,13 @@
\input{sections/proximal_decoding.tex}
\input{sections/lp_dec_using_admm.tex}
\input{sections/comparison.tex}
\input{sections/conclusion.tex}
\input{sections/question_slide.tex}
\begin{frame}[allowframebreaks]
\frametitle{Bibliography}
\printbibliography[heading=none]
\end{frame}
% \begin{frame}[allowframebreaks]
% \frametitle{Bibliography}
% \printbibliography[heading=none]
% \end{frame}
\input{sections/appendix.tex}

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@ -27,7 +27,7 @@
ylabel={$\gamma$},
zlabel={BER},
width=1.2\textwidth,
height=0.85\textwidth,
height=0.825\textwidth,
legend pos=outer north east,]
\addplot3[surf,
@ -50,10 +50,10 @@
\end{axis}
\end{tikzpicture}
\vspace*{-1mm}
\vspace*{-2mm}
\caption{$\left( 3, 6 \right)$-regular LDPC code with $n=96, k=48$
\cite[\text{96.3.965}]{mackay_enc}}
\citereference{Mac23, 96.3.965}}
\end{subfigure}%
\begin{subfigure}[t]{0.33\textwidth}
\centering
@ -65,7 +65,7 @@
ylabel={$\gamma$},
zlabel={BER},
width=1.2\textwidth,
height=0.85\textwidth,
height=0.825\textwidth,
legend pos=outer north east,]
\addplot3[surf,
@ -88,10 +88,10 @@
\end{axis}
\end{tikzpicture}
\vspace*{-1mm}
\vspace*{-2mm}
\caption{$\left( 3, 6 \right)$-regular LDPC code with $n=204, k=102$
\cite[\text{204.33.484}]{mackay_enc}}
\citereference{Mac23, 204.33.484}}
\end{subfigure}%
\begin{subfigure}[t]{0.33\textwidth}
\centering
@ -103,7 +103,7 @@
ylabel={$\gamma$},
zlabel={BER},
width=1.2\textwidth,
height=0.85\textwidth,
height=0.825\textwidth,
legend pos=outer north east,]
\addplot3[surf,
@ -126,12 +126,14 @@
\end{axis}
\end{tikzpicture}
\vspace*{-1mm}
\vspace*{-2mm}
\caption{$\left( 3, 6 \right)$-regular LDPC code with $n=408, k=204$
\cite[\text{408.33.844}]{mackay_enc}}
\citereference{Mac23, 408.33.844}}
\end{subfigure}%
\vspace*{-2mm}
\begin{subfigure}[t]{0.33\textwidth}
\centering
@ -142,7 +144,7 @@
ylabel={$\gamma$},
zlabel={BER},
width=1.2\textwidth,
height=0.85\textwidth,
height=0.825\textwidth,
legend pos=outer north east,]
\addplot3[surf,
@ -165,7 +167,7 @@
\end{axis}
\end{tikzpicture}
\vspace*{-1mm}
\vspace*{-2mm}
\caption{BCH code with $n=31, k=26$}
\end{subfigure}%
@ -179,7 +181,7 @@
ylabel={$\gamma$},
zlabel={BER},
width=1.2\textwidth,
height=0.85\textwidth,
height=0.825\textwidth,
legend pos=outer north east,]
\addplot3[surf,
@ -202,10 +204,10 @@
\end{axis}
\end{tikzpicture}
\vspace*{-1mm}
\vspace*{-2mm}
\caption{$\left( 5, 10 \right)$-regular LDPC code with $n=204, k=102$
\cite[\text{204.55.187}]{mackay_enc}}
\citereference{Mac23, 204.55.187}}
\end{subfigure}%
\begin{subfigure}[t]{0.33\textwidth}
\centering
@ -217,7 +219,7 @@
ylabel={$\gamma$},
zlabel={BER},
width=1.2\textwidth,
height=0.85\textwidth,
height=0.825\textwidth,
legend pos=outer north east,]
\addplot3[surf,
@ -240,10 +242,10 @@
\end{axis}
\end{tikzpicture}
\vspace*{-1mm}
\vspace*{-2mm}
\caption{LDPC code (progressive edge growth construction) with $n=504, k=252$
\cite[\text{PEGReg252x504}]{mackay_enc}}
\citereference{Mac23, PEGReg252x504}}
\end{subfigure}%
\end{figure}
\end{minipage}%
@ -271,6 +273,11 @@
\end{tikzpicture}
\end{figure}
\end{minipage}
\vspace*{-1mm}
\addreference{Mac23}{David J.C. MacKay: \emph{Encyclopedia of Sparse Graph Codes}.
Jan. 2023. URL: \url{http://www.inference.org.uk/mackay/codes/data.html}.}
\end{frame}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@ -296,7 +303,7 @@
xlabel={$\rho$}, ylabel={Avg. \# iter.},
ymode=log,
width=1.2\textwidth,
height=0.85\textwidth,
height=0.825\textwidth,
]
\addplot[ForestGreen, line width=1pt]
table [col sep=comma, x=rho, y=k_avg,
@ -313,10 +320,10 @@
\end{axis}
\end{tikzpicture}
\vspace*{-1mm}
\vspace*{-2mm}
\caption{$\left( 3, 6 \right)$-regular LDPC code with $n=96, k=48$
\cite[\text{96.3.965}]{mackay_enc}}
\citereference{Mac23, 96.3.965}}
\end{subfigure}%
\begin{subfigure}[t]{0.33\textwidth}
\centering
@ -327,7 +334,7 @@
xlabel={$\rho$}, ylabel={Avg. \# iter.},
ymode=log,
width=1.2\textwidth,
height=0.85\textwidth,
height=0.825\textwidth,
]
\addplot[ForestGreen, line width=1pt]
table [col sep=comma, x=rho, y=k_avg,
@ -344,10 +351,10 @@
\end{axis}
\end{tikzpicture}
\vspace*{-1mm}
\vspace*{-2mm}
\caption{$\left( 3, 6 \right)$-regular LDPC code with $n=204, k=102$
\cite[\text{204.33.484}]{mackay_enc}}
\citereference{Mac23, 204.33.484}}
\end{subfigure}%
\begin{subfigure}[t]{0.33\textwidth}
\centering
@ -358,7 +365,7 @@
xlabel={$\rho$}, ylabel={Avg. \# iter.},
ymode=log,
width=1.2\textwidth,
height=0.85\textwidth,
height=0.825\textwidth,
]
\addplot[ForestGreen, line width=1pt]
table [col sep=comma, x=rho, y=k_avg,
@ -375,12 +382,14 @@
\end{axis}
\end{tikzpicture}
\vspace*{-1mm}
\vspace*{-2mm}
\caption{$\left( 3, 6 \right)$-regular LDPC code with $n=408, k=204$
\cite[\text{408.33.844}]{mackay_enc}}
\citereference{Mac23, 408.33.844}}
\end{subfigure}%
\vspace*{-2mm}
\begin{subfigure}[t]{0.33\textwidth}
\centering
@ -390,7 +399,7 @@
xlabel={$\rho$}, ylabel={Avg. \# iter.},
ymode=log,
width=1.2\textwidth,
height=0.85\textwidth,
height=0.825\textwidth,
]
\addplot[ForestGreen, line width=1pt]
table [col sep=comma, x=rho, y=k_avg,
@ -407,7 +416,7 @@
\end{axis}
\end{tikzpicture}
\vspace*{-1mm}
\vspace*{-2mm}
\caption{BCH code with $n=31, k=26$}
\end{subfigure}%
@ -420,7 +429,7 @@
xlabel={$\rho$}, ylabel={Avg. \# iter.},
ymode=log,
width=1.2\textwidth,
height=0.85\textwidth,
height=0.825\textwidth,
]
\addplot[ForestGreen, line width=1pt]
table [col sep=comma, x=rho, y=k_avg,
@ -437,10 +446,10 @@
\end{axis}
\end{tikzpicture}
\vspace*{-1mm}
\vspace*{-2mm}
\caption{$\left( 5, 10 \right)$-regular LDPC code with $n=204, k=102$
\cite[\text{204.55.187}]{mackay_enc}}
\citereference{Mac23, 204.55.187}}
\end{subfigure}%
\begin{subfigure}[t]{0.33\textwidth}
\centering
@ -451,7 +460,7 @@
xlabel={$\rho$}, ylabel={Avg. \# iter.},
ymode=log,
width=1.2\textwidth,
height=0.85\textwidth,
height=0.825\textwidth,
]
\addplot[ForestGreen, line width=1pt]
table [col sep=comma, x=rho, y=k_avg,
@ -468,10 +477,10 @@
\end{axis}
\end{tikzpicture}
\vspace*{-1mm}
\vspace*{-2mm}
\caption{LDPC code (progressive edge growth construction) with $n=504, k=252$
\cite[\text{PEGReg252x504}]{mackay_enc}}
\citereference{Mac23, PEGReg252x504}}
\end{subfigure}%
\end{figure}
\end{minipage}%
@ -500,5 +509,10 @@
\end{tikzpicture}
\end{figure}
\end{minipage}
\vspace*{-1mm}
\addreference{Mac23}{David J.C. MacKay: \emph{Encyclopedia of Sparse Graph Codes}.
Jan. 2023. URL: \url{http://www.inference.org.uk/mackay/codes/data.html}.}
\end{frame}

View File

@ -11,8 +11,10 @@
\begin{frame}[t]
\frametitle{Comparison: Convergence Behavior}
\vspace*{-3mm}
\begin{itemize}
\item (3,6) regular LDPC code with $n=204, k=102$ \cite[\text{204.33.484}]{mackay_enc}
\item (3,6) regular LDPC code with $n=204, k=102$ \citereference{Mac23, 204.33.484}
\end{itemize}
\begin{figure}[H]
@ -105,6 +107,14 @@
\begin{itemize}
\item Minimum number of iterations independant of SNR
\end{itemize}
\bigskip
\smallskip
\smallskip
\smallskip
\addreference{Mac23}{David J.C. MacKay: \emph{Encyclopedia of Sparse Graph Codes}.
Jan. 2023. URL: \url{http://www.inference.org.uk/mackay/codes/data.html}.}
\end{frame}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@ -114,11 +124,11 @@
\vspace*{-6.5mm}
\begin{itemize}
\item The points shown are from the following codes: BCH $\left( 31, 11 \right)$;
BCH $\left( 31, 26 \right)$; \\
\cite[\text{96.3.965; 204.33.484; 204.55.187; 408.33.844; PEGReg252x504}]{mackay_enc}
\item Codes: BCH $\left( 31, 11 \right)$; BCH $\left( 31, 26 \right)$;
\citereference{Mac23, 96.3.965; 204.33.484; 204.55.187; 408.33.844; PEGReg252x504}
\item Measured performance: $\sim\SI{10000}{}$ frames/s
on Intel Core i7-7700HQ @ 2.80GHz; $n=204$
\item Both algorithms are $\mathcal{O}\left( n \right)$ on average
\end{itemize}
\begin{figure}[H]
@ -130,8 +140,8 @@
xlabel={$n$}, ylabel={time per frame (s)},
legend style={at={(0.05,0.6)},anchor=south west},
legend cell align={left},
width=0.45\textwidth,
height=0.3375\textwidth,
width=0.43\textwidth,
height=0.32\textwidth,
]
\addplot[RedOrange, only marks, mark=square*]
table [col sep=comma, x=n, y=spf]
@ -151,10 +161,12 @@
\end{tikzpicture}
\end{figure}
\begin{itemize}
\item Both algorithms are $\mathcal{O}\left( n \right)$ on average
\item LP decoding implementation significantly faster
\end{itemize}
\bigskip
\smallskip
\smallskip
\addreference{Mac23}{David J.C. MacKay: \emph{Encyclopedia of Sparse Graph Codes}.
Jan. 2023. URL: \url{http://www.inference.org.uk/mackay/codes/data.html}.}
\end{frame}
@ -165,7 +177,7 @@
\vspace{-0.5cm}
\begin{itemize}
\item (3,6) regular LDPC code with $n=204, k=102$ \cite[\text{204.33.484}]{mackay_enc}
\item (3,6) regular LDPC code with $n=204, k=102$ \citereference{Mac23, 204.33.484}
\end{itemize}
\begin{figure}[H]
@ -179,8 +191,8 @@
legend columns=2,
legend style={at={(0.5,-0.45)},anchor=south},
ymax=1.5, ymin=3e-8,
width=0.48\textwidth,
height=0.35\textwidth,
width=0.45\textwidth,
height=0.33\textwidth,
]
\addplot[RedOrange, mark=*, line width=1pt]
table [x=SNR, y=BER, col sep=comma, discard if not={gamma}{0.05}]
@ -208,8 +220,8 @@
legend columns=2,
legend style={at={(0.5,-0.45)},anchor=south},
ymax=1.5, ymin=3e-8,
width=0.48\textwidth,
height=0.35\textwidth,
width=0.45\textwidth,
height=0.33\textwidth,
]
\addplot[RedOrange, mark=*, solid, line width=1pt]
@ -256,6 +268,13 @@
\end{axis}
\end{tikzpicture}
\end{figure}
\smallskip
\smallskip
\smallskip
\addreference{Mac23}{David J.C. MacKay: \emph{Encyclopedia of Sparse Graph Codes}.
Jan. 2023. URL: \url{http://www.inference.org.uk/mackay/codes/data.html}.}
\end{frame}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@ -318,7 +337,7 @@
\centering
\begin{figure}[H]
\vspace*{-0.7cm}
\vspace*{-0.8cm}
\centering
\begin{subfigure}[t]{0.33\textwidth}
@ -331,7 +350,7 @@
ymode=log,
ymax=1.5, ymin=8e-5,
width=1.2\textwidth,
height=0.85\textwidth,
height=0.825\textwidth,
]
\addplot[RedOrange, line width=1pt, mark=*, solid]
@ -351,10 +370,10 @@
\end{axis}
\end{tikzpicture}
\vspace*{-1mm}
\vspace*{-2mm}
\caption{$\left( 3, 6 \right)$-regular LDPC code with $n=96, k=48$
\cite[\text{96.3.965}]{mackay_enc}}
\citereference{Mac23, 96.33.965}}
\end{subfigure}%
\begin{subfigure}[t]{0.33\textwidth}
\centering
@ -366,7 +385,7 @@
ymode=log,
ymax=1.5, ymin=8e-5,
width=1.2\textwidth,
height=0.85\textwidth,
height=0.825\textwidth,
]
\addplot[RedOrange, line width=1pt, mark=*]
@ -390,10 +409,10 @@
\end{axis}
\end{tikzpicture}
\vspace*{-1mm}
\vspace*{-2mm}
\caption{$\left( 3, 6 \right)$-regular LDPC code with $n=204, k=102$
\cite[\text{204.33.484}]{mackay_enc}}
\citereference{Mac23, 204.33.484}}
\end{subfigure}%
\begin{subfigure}[t]{0.33\textwidth}
\centering
@ -405,7 +424,7 @@
ymode=log,
ymax=1.5, ymin=8e-5,
width=1.2\textwidth,
height=0.85\textwidth,
height=0.825\textwidth,
]
\addplot[RedOrange, line width=1pt, mark=*]
@ -421,12 +440,14 @@
\end{axis}
\end{tikzpicture}
\vspace*{-1mm}
\vspace*{-2mm}
\caption{$\left( 3, 6 \right)$-regular LDPC code with $n=408, k=204$
\cite[\text{408.33.844}]{mackay_enc}}
\citereference{Mac23, 408.33.844}}
\end{subfigure}%
\vspace*{-2mm}
\begin{subfigure}[t]{0.33\textwidth}
\centering
@ -437,7 +458,7 @@
ymode=log,
ymax=1.5, ymin=8e-5,
width=1.2\textwidth,
height=0.85\textwidth,
height=0.825\textwidth,
]
\addplot[RedOrange, line width=1pt, mark=*]
@ -459,7 +480,7 @@
\end{axis}
\end{tikzpicture}
\vspace*{-1mm}
\vspace*{-2mm}
\caption{BCH code with $n=31, k=26$}
\end{subfigure}%
@ -473,7 +494,7 @@
ymode=log,
ymax=1.5, ymin=8e-5,
width=1.2\textwidth,
height=0.85\textwidth,
height=0.825\textwidth,
]
\addplot[RedOrange, line width=1pt, mark=*]
@ -488,10 +509,10 @@
\end{axis}
\end{tikzpicture}
\vspace*{-1mm}
\vspace*{-2mm}
\caption{$\left( 5, 10 \right)$-regular LDPC code with $n=204, k=102$
\cite[\text{204.55.187}]{mackay_enc}}
\citereference{Mac23, 204.55.187}}
\end{subfigure}%
\begin{subfigure}[t]{0.33\textwidth}
\centering
@ -503,7 +524,7 @@
ymode=log,
ymax=1.5, ymin=8e-5,
width=1.2\textwidth,
height=0.85\textwidth,
height=0.825\textwidth,
]
\addplot[RedOrange, line width=1pt, mark=*]
@ -519,10 +540,10 @@
\end{axis}
\end{tikzpicture}
\vspace*{-1mm}
\vspace*{-2mm}
\caption{LDPC code (progressive edge growth construction) with $n=504, k=252$
\cite[\text{PEGReg252x504}]{mackay_enc}}
\citereference{Mac23, PEGReg252x504}}
\end{subfigure}%
\end{figure}
\end{minipage}%
@ -548,19 +569,17 @@
\addlegendimage{NavyBlue, line width=1pt, mark=*}
\addlegendentry{ADMM}
% \addlegendimage{RoyalPurple, line width=1pt, mark=*}
% \addlegendentry{BP}
\addlegendimage{Black, line width=1pt, mark=*}
\addlegendentry{ML}
% \addlegendimage{PineGreen, line width=1pt, mark=triangle*, solid}
% \addlegendentry{ML}
\end{axis}
\end{tikzpicture}
\end{figure}
\end{minipage}
\vspace*{-1mm}
\addreference{Mac23}{David J.C. MacKay: \emph{Encyclopedia of Sparse Graph Codes}.
Jan. 2023. URL: \url{http://www.inference.org.uk/mackay/codes/data.html}.}
\end{frame}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@ -700,24 +719,3 @@ return $\tilde{\boldsymbol{c}}$
\end{figure}%
\end{frame}
\begin{frame}[t]
\frametitle{Conclusion}
\begin{itemize}
\item Analysis of the general behavior of the two decoding algorithms
\begin{itemize}
\item Parameter choice based on decoding performance and time complexity
\item Verification of theoretical considerations with simulation results
\end{itemize}
\item Suggestion for improvement of proximal decoding
\begin{itemize}
\item Addition of "ML-in-the-List" step
\item Up to $\sim \SI{1}{dB}$ gain under certain conditions
\end{itemize}
\item Comparison
\begin{itemize}
\item based on simulation results
\item based on their theoretical structure
\end{itemize}
\end{itemize}
\end{frame}

View File

@ -0,0 +1,26 @@
\section{Conclusion and Outlook}%
\label{sec:Comparison}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\begin{frame}[t]
\frametitle{Conclusion}
\begin{itemize}
\item Analysis of the general behavior of the two decoding algorithms
\begin{itemize}
\item Parameter choice based on decoding performance and time complexity
\item Verification of theoretical considerations with simulation results
\end{itemize}
\item Suggestion for improvement of proximal decoding
\begin{itemize}
\item Addition of "ML-in-the-List" step
\item Up to $\sim \SI{1}{dB}$ gain under certain conditions
\end{itemize}
\item Comparison
\begin{itemize}
\item based on simulation results
\item based on their theoretical structure
\end{itemize}
\end{itemize}
\end{frame}

View File

@ -7,7 +7,9 @@
\label{sub:LP Decoding using ADMM}
\begin{frame}[t]
\frametitle{LP Decoding \cite{feldman_paper}}
\frametitle{LP Decoding \citereference{FWK05}}
\vspace*{-3mm}
\begin{itemize}
\item General reformulation of ML decoding as a linear program (LP)
@ -36,6 +38,13 @@
\end{align*}
\item Goal: relaxation of constraints to make a practical solution to the problem feasible
\end{itemize}
\bigskip
\bigskip
\addreference{FWK05}{J. Feldman; M.J. Wainwright; D.R. Karger: \emph{Using linear programming
to Decode Binary linear codes}.
IEEE Transactions on Information Theory 51.3 (2005), pp. 954972.}
\end{frame}
@ -656,12 +665,16 @@
\begin{frame}[t]
\frametitle{LP Decoding using ADMM}
\vspace*{-4mm}
\begin{itemize}
\item Solution using the \textit{alternating direction method of multipliers} (ADMM)
\citereference{$\text{Bar}^+\text{13}$}
\item Slight reformulation of the LCLP:
\begin{align*}
\begin{aligned}
\text{minimize}\hspace{2mm} &\boldsymbol{\gamma}^\text{T}\tilde{\boldsymbol{c}}
\text{minimize}\hspace{2mm} &\boldsymbol{\gamma}^\text{T}
\tilde{\boldsymbol{c}}
+ \sum_{j\in\mathcal{J}} g_j\left( \boldsymbol{z}_j \right) \\
\text{subject to}\hspace{2mm} &
\boldsymbol{T}_j\tilde{\boldsymbol{c}} = \boldsymbol{z}_j, \hspace{2mm}
@ -692,6 +705,12 @@
% - \boldsymbol{z}_j + \boldsymbol{u}_j\right\Vert \right)
\end{alignat*}
\end{itemize}
\bigskip
\addreference{$\text{Bar}^+\text{13}$}{Siddharth Barman et al.:
\emph{Decomposition Methods for Large Scale LP Decoding}.
IEEE Transactions on Information Theory 59.12 (2013), pp. 78707886.}
\end{frame}
@ -703,12 +722,14 @@
\begin{itemize}
\item Convergence properties enhanced by over-relaxation with parameter $\rho$
\item Simplified rules%
\footnote{$\left( \boldsymbol{z}_j \right)_i $ is a slight abuse of notation.
What is actually meant is the component of $\boldsymbol{z}_j$ that is associated
with the VN $i$, i.e., $\left( \boldsymbol{T}_j^\text{T}
\boldsymbol{z}_j \right)_i$.\\
The same is true for $\left( \boldsymbol{u}_j \right)_i$}:
\item Simplified rules:
% \footnote{$\left( \boldsymbol{z}_j \right)_i $ is a slight abuse of notation.
% What is actually meant is the component of $\boldsymbol{z}_j$ that is associated
% with the VN $i$, i.e., $\left( \boldsymbol{T}_j^\text{T}
% \boldsymbol{z}_j \right)_i$.\\
% The same is true for $\left( \boldsymbol{u}_j \right)_i$}:
\vspace*{-3mm}
\begin{alignat*}{3}
\tilde{c}_i &\leftarrow \frac{1}{\left| N_v\left( i \right) \right|} \left(
@ -726,12 +747,31 @@
- \boldsymbol{z}_j
\hspace{5mm} && \forall j\in\mathcal{J}
\end{alignat*}
\vspace*{2mm}
\item The projections $\Pi_{\mathcal{P}_{d_j}}, \hspace{1mm} j\in\mathcal{J}$
are the main computational effort
\item Many approaches exist \cite{original_admm}, \cite{efficient_lp_dec_admm},
\cite{lautern}
\item The approach chosen here is the one described in \cite{original_admm}
\item Many approaches exist \citereference{$\text{Bar}^+\text{13}$},
\citereference{ZS13}, \citereference{$\text{Gen}^+\text{20}$}
\item The approach chosen here is the one described in
\citereference{$\text{Bar}^+\text{13}$}
\end{itemize}
\bigskip
\smallskip
\addreferences
{$\text{Bar}^+\text{13}$}{Siddharth Barman et al.:
\emph{Decomposition Methods for Large Scale LP Decoding}.
IEEE Transactions on Information Theory 59.12 (2013), pp. 78707886.}
{ZS13}{Xiaojie Zhang; Paul H. Siegel: \emph{Efficient iterative LP decoding
of LDPC codes with alternating direction method of multipliers}.
2013 IEEE International Symposium on Information Theory. 2013, pp. 15011505.}
{$\text{Gen}^+\text{20}$}{Florian Gensheimer et al.:
\emph{A Reduced-Complexity Projection Algorithm for ADMM-Based LP Decoding}.
IEEE Transactions on Information Theory 66.8 (2020), pp. 48194833.}
\stopreferences
\end{frame}
@ -827,9 +867,11 @@
\begin{frame}[t]
\frametitle{LP Decoding using ADMM: Frame Error Rate}
\vspace*{-6mm}
\begin{itemize}
\item ``Margulis'' LDPC code with $n = 2640$, $k = 1320$
\cite[\text{Margulis2640.1320.3}]{mackay_enc}
\citereference{Mac23, Margulis2640.1320.3}
% ; $K=200, \mu = 3.3, \rho=1.9,
% \epsilon_{\text{pri}} = 10^{-5}, \epsilon_{\text{dual}} = 10^{-5}$
\end{itemize}
@ -852,50 +894,7 @@
discard if gt={SNR}{2.2},
]
{res/admm/fer_paper_margulis.csv};
\addlegendentry{ADMM (Barman et al.)}
\addplot[RoyalPurple, line width=1pt, mark=*]
table [col sep=comma, x=SNR, y=FER, discard if gt={SNR}{2.2},]
{res/generic/fer_bp_mackay_margulis.csv};
\addlegendentry{BP (Barman et al.)}
\end{axis}
\end{tikzpicture}
\end{figure}
\begin{itemize}
\item Comparison of simulation with results from Barman et al. \cite{original_admm}
\end{itemize}
\end{frame}
\begin{frame}[t]
\frametitle{LP Decoding using ADMM: Frame Error Rate}
\begin{itemize}
\item ``Margulis'' LDPC code with $n = 2640$, $k = 1320$
\cite[\text{Margulis2640.1320.3}]{mackay_enc}
% ; $K=200, \mu = 3.3, \rho=1.9,
% \epsilon_{\text{pri}} = 10^{-5}, \epsilon_{\text{dual}} = 10^{-5}$
\end{itemize}
\begin{figure}[H]
\centering
\begin{tikzpicture}
\begin{axis}[
grid=both,
xlabel={$E_b / N_0 \left( \text{dB} \right) $}, ylabel={FER},
ymode=log,
width=0.45\textwidth,
height=0.325\textwidth,
%legend style={at={(0.03,0.04)},anchor=south west},
legend pos=outer north east,
]
\addplot[Emerald, line width=1pt, mark=*]
table [col sep=comma, x=SNR, y=FER,
discard if gt={SNR}{2.2},
]
{res/admm/fer_paper_margulis.csv};
\addlegendentry{ADMM (Barman et al.)}
\addlegendentry{ADMM \citereference{$\text{Bar}^+\text{13}$}}
\addplot[NavyBlue, mark=*, line width=1pt, densely dashed]
table [col sep=comma, x=SNR, y=FER,]
{res/admm/ber_margulis264013203.csv};
@ -903,14 +902,25 @@
\addplot[RoyalPurple, line width=1pt, mark=*]
table [col sep=comma, x=SNR, y=FER, discard if gt={SNR}{2.2},]
{res/generic/fer_bp_mackay_margulis.csv};
\addlegendentry{BP (Barman et al.)}
\addlegendentry{BP \citereference{$\text{Bar}^+\text{13}$}}
\end{axis}
\end{tikzpicture}
\end{figure}%
\begin{itemize}
\item Comparison of simulation with results from Barman et al. \cite{original_admm}
\item Comparison of simulation with results from Barman et al.
\citereference{$\text{Bar}^+\text{13}$}
\end{itemize}
\bigskip
\addreferences
{Mac23}{David J.C. MacKay: \emph{Encyclopedia of Sparse Graph Codes}.
Jan. 2023. URL: \url{http://www.inference.org.uk/mackay/codes/data.html}.}
{$\text{Bar}^+\text{13}$}{Siddharth Barman et al.:
\emph{Decomposition Methods for Large Scale LP Decoding}.
IEEE Transactions on Information Theory 59.12 (2013), pp. 78707886.}
\stopreferences
\end{frame}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@ -918,8 +928,10 @@
\frametitle{LP Decoding using ADMM: Choice of Penalty\\
Parameters}
\vspace*{-5mm}
\begin{itemize}
\item (3,6) regular LDPC code with $n=204, k=102$ \cite[\text{204.33.484}]{mackay_enc}
\item (3,6) regular LDPC code with $n=204, k=102$ \citereference{Mac23, 204.33.484}
\end{itemize}
\begin{figure}[H]
@ -933,8 +945,8 @@
grid=both,
xlabel={$\mu$}, ylabel={FER},
ymode=log,
width=0.9\textwidth,
height=0.675\textwidth,
width=0.8\textwidth,
height=0.6\textwidth,
]
\addplot[ForestGreen, line width=1pt, densely dashed, mark=*]
table [col sep=comma, x=mu, y=FER,
@ -959,8 +971,8 @@
grid=both,
xlabel={$\rho$}, ylabel={FER},
ymode=log,
width=0.9\textwidth,
height=0.675\textwidth,
width=0.8\textwidth,
height=0.6\textwidth,
]
\addplot[ForestGreen, line width=1pt, densely dashed, mark=*]
table [col sep=comma, x=rho, y=FER,
@ -1003,6 +1015,11 @@
\item Similar to $\gamma$ with proximal decoding: no clear optimum
\end{itemize}
\bigskip
\bigskip
\addreference{Mac23}{David J.C. MacKay: \emph{Encyclopedia of Sparse Graph Codes}.
Jan. 2023. URL: \url{http://www.inference.org.uk/mackay/codes/data.html}.}
\end{frame}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@ -1010,8 +1027,10 @@
\frametitle{LP Decoding using ADMM: Choice of Penalty\\
Parameters}
\vspace*{-5mm}
\begin{itemize}
\item (3,6) regular LDPC code with $n=204, k=102$ \cite[\text{204.33.484}]{mackay_enc}
\item (3,6) regular LDPC code with $n=204, k=102$ \citereference{Mac23, 204.33.484}
\end{itemize}
\begin{figure}[H]
@ -1024,8 +1043,8 @@
\begin{axis}[
grid=both,
xlabel={$\mu$}, ylabel={Average \# of iterations},
width=0.9\textwidth,
height=0.675\textwidth,
width=0.8\textwidth,
height=0.6\textwidth,
]
\addplot[ForestGreen, line width=1pt, densely dashed, mark=*]
table [col sep=comma, x=mu, y=k_avg,
@ -1049,8 +1068,8 @@
\begin{axis}[
grid=both,
xlabel={$\rho$}, ylabel={Average \# of iterations},
width=0.9\textwidth,
height=0.675\textwidth,
width=0.8\textwidth,
height=0.6\textwidth,
]
\addplot[ForestGreen, line width=1pt, densely dashed, mark=*]
table [col sep=comma, x=rho, y=k_avg,
@ -1092,5 +1111,13 @@
\begin{itemize}
\item For lower decoding time, choose low $\mu$ and high $\rho$
\end{itemize}
\bigskip
\smallskip
\smallskip
\smallskip
\addreference{Mac23}{David J.C. MacKay: \emph{Encyclopedia of Sparse Graph Codes}.
Jan. 2023. URL: \url{http://www.inference.org.uk/mackay/codes/data.html}.}
\end{frame}

View File

@ -7,9 +7,9 @@
\label{sub:Decoding Algorithm}
\begin{frame}[t]
\frametitle{Proximal Decoding: General Idea \cite{proximal_paper}}
\frametitle{Proximal Decoding: General Idea \citereference{WT22}}
\vspace*{-0.3cm}
\vspace*{-0.7cm}
\begin{itemize}
\item MAP rule as continuous maximization problem:
@ -59,6 +59,13 @@
\end{minipage}
\hfill
\end{itemize}
\smallskip
\smallskip
\addreference{WT22}{Tadashi Wadayama; Satoshi Takabe: \emph{Proximal Decoding for LDPC
Codes}. IEICE Transactions on Fundamentals of Electronics, Communications and Computer
Sciences advpub (2022), 2022TAP0002.}
\end{frame}
@ -66,6 +73,8 @@
\begin{frame}[t]
\frametitle{Proximal Decoding: General Idea}
\vspace*{-3mm}
\begin{itemize}
\item Objective function:
\begin{align*}
@ -74,7 +83,7 @@
+ \gamma h\left( \tilde{\boldsymbol{x}} \right)
\end{align*}
\note{Notational difference between $f$ and $f_X$ or $f_Y$}
\item Proximal operator \cite{proximal_algorithms}:
\item Proximal operator \citereference{PB14}:
\begin{align*}
\text{prox}_{\gamma h} \left( \tilde{\boldsymbol{x}} \right) &\equiv
\argmin_{\boldsymbol{t}\in\mathbb{R}^n}
@ -96,6 +105,11 @@
\hspace{10mm} \text{``Code proximal step''}
\end{align*}
\end{itemize}
\bigskip
\addreference{PB14}{Neal Parikh; Stephen Boyd: \emph{Proximal Algorithms}.
Found. Trends Optim. 1.3 (Jan. 2014), pp. 127239.}
\end{frame}
@ -103,7 +117,7 @@
\begin{frame}[t, fragile]
\frametitle{Proximal Decoding: Algorithm}
\begin{itemize}
\item Iterative decoding algorithm \cite{proximal_paper}:
\item Iterative decoding algorithm:
\end{itemize}
\vspace{2mm}
@ -130,8 +144,10 @@ return $\boldsymbol{\hat{c}}$
\begin{frame}[t]
\frametitle{Proximal Decoding: Bit Error Rate}
\vspace*{-7mm}
\begin{itemize}
\item (3,6) regular LDPC code with $n=204, k=102$ \cite[\text{204.33.484}]{mackay_enc}
\item (3,6) regular LDPC code with $n=204, k=102$ \citereference{Mac23, 204.33.484}
\end{itemize}
\begin{figure}[H]
@ -159,7 +175,7 @@ return $\boldsymbol{\hat{c}}$
\addlegendentry{$\gamma = 0.15$}
\addplot [ForestGreen, mark=*, line width=1pt]
table [x=SNR, y=gamma_0_15, col sep=comma] {res/ber_paper.csv};
\addlegendentry{$\gamma = 0.15$ (Wadayama et al.)}
\addlegendentry{$\gamma = 0.15$ \citereference{WT22}}
\addplot [NavyBlue, mark=triangle, dashed, line width=1pt]
table [x=SNR, y=BER, col sep=comma,
@ -169,7 +185,7 @@ return $\boldsymbol{\hat{c}}$
\addlegendentry{$\gamma = 0.01$}
\addplot [NavyBlue, mark=*, line width=1pt]
table [x=SNR, y=gamma_0_01, col sep=comma] {res/ber_paper.csv};
\addlegendentry{$\gamma = 0.01$ (Wadayama et al.)}
\addlegendentry{$\gamma = 0.01$ \citereference{WT22}}
\addplot [RedOrange, mark=triangle, dashed, line width=1pt]
table [x=SNR, y=BER, col sep=comma,
@ -179,19 +195,29 @@ return $\boldsymbol{\hat{c}}$
\addlegendentry{$\gamma = 0.05$}
\addplot [RedOrange, mark=*, line width=1pt]
table [x=SNR, y=gamma_0_05, col sep=comma] {res/ber_paper.csv};
\addlegendentry{$\gamma = 0.05$ (Wadayama et al.)}
\addlegendentry{$\gamma = 0.05$ \citereference{WT22}}
\addplot [RoyalPurple, mark=*, line width=1pt]
table [x=SNR, y=BP, col sep=comma] {res/ber_paper.csv};
\addlegendentry{BP}
\addlegendentry{BP \citereference{WT22}}
\end{axis}
\end{tikzpicture}
\end{figure}
\vspace*{-2mm}
\begin{itemize}
\item Comparison of simulation with results of Wadayama et al. \cite{proximal_paper}
\item Comparison of simulation with results of Wadayama et al. \citereference{WT22}
\end{itemize}
\bigskip
\addreference{WT22}{Tadashi Wadayama; Satoshi Takabe: \emph{Proximal Decoding for LDPC
Codes}. IEICE Transactions on Fundamentals of Electronics, Communications and Computer
Sciences advpub (2022), 2022TAP0002.}
\addreference{Mac23}{David J.C. MacKay: \emph{Encyclopedia of Sparse Graph Codes}.
Jan. 2023. URL: \url{http://www.inference.org.uk/mackay/codes/data.html}}.
\end{frame}
@ -199,8 +225,10 @@ return $\boldsymbol{\hat{c}}$
\begin{frame}[t]
\frametitle{Proximal Decoding: Choice of $\gamma$}
\vspace*{-5mm}
\begin{itemize}
\item (3,6) regular LDPC code with $n=204, k=102$ \cite[\text{204.33.484}]{mackay_enc}
\item (3,6) regular LDPC code with $n=204, k=102$ \citereference{Mac23, 204.33.484}
\end{itemize}
\begin{figure}[H]
@ -273,6 +301,12 @@ return $\boldsymbol{\hat{c}}$
\begin{itemize}
\item Not great benefit in finding the optimal value for $\gamma$
\end{itemize}
\bigskip
\addreference{Mac23}{David J.C. MacKay: \emph{Encyclopedia of Sparse Graph Codes}.
Jan. 2023. URL: \url{http://www.inference.org.uk/mackay/codes/data.html}}.
\end{frame}
@ -495,12 +529,14 @@ return $\boldsymbol{\hat{c}}$
\begin{frame}[t, fragile]
\frametitle{Proximal Decoding: Frame Error Rate}
\vspace*{-3mm}
\begin{itemize}
\item (3,6) regular LDPC code with $n=204$,\\
$k=102$ \cite[\text{204.33.484}]{mackay_enc}
$k=102$ \citereference{Mac23, 204.33.484}
\end{itemize}
\vspace*{-5mm}
\vspace*{-2mm}
\begin{minipage}{.4\textwidth}
\centering
@ -521,6 +557,11 @@ end for
return $\boldsymbol{\hat{c}}$
\end{algorithm}
\end{figure}
\vspace*{-4mm}
\hspace*{-4mm}
\addreference{Mac23}{David J.C. MacKay: \emph{Encyclopedia of Sparse Graph Codes}.
Jan. 2023. URL: \url{http://www.inference.org.uk/mackay/codes/data.html}.}
\end{minipage}%
\begin{minipage}{.6\textwidth}
\centering
@ -854,8 +895,8 @@ return $\boldsymbol{\hat{c}}$
\end{axis}
\end{tikzpicture}
\caption{$\nabla L \left(\boldsymbol{y} \mid \tilde{\boldsymbol{x}} \right)$
for a repetition code with $n=2$\footnotemark}
\caption{$\nabla L \left(\boldsymbol{y} \mid \tilde{\boldsymbol{x}} \right)$%
\footnotemark{} for a repetition code with $n=2$}
\end{subfigure}%
\begin{subfigure}[c]{0.5\textwidth}
\centering
@ -894,9 +935,7 @@ return $\boldsymbol{\hat{c}}$
\footnotetext{In an AWGN Channel $\nabla L\left( \boldsymbol{y} \mid
\tilde{\boldsymbol{x}}\right)
\propto \left( \tilde{\boldsymbol{x}} - \boldsymbol{y} \right)$
\cite[Sec. 4.1]{proximal_paper}}
\propto \left( \tilde{\boldsymbol{x}} - \boldsymbol{y} \right)$}
\end{frame}
@ -904,9 +943,11 @@ return $\boldsymbol{\hat{c}}$
\begin{frame}[t]
\frametitle{Proximal Decoder: Oscillation of $\nabla h\left( \tilde{\boldsymbol{x}} \right) $}
\vspace*{-3mm}
\begin{itemize}
\item Single decoding using a (3,6) regular LDPC code with $n=204, k=102$
\cite[\text{204.33.484}]{mackay_enc}
\citereference{Mac23, 204.33.484}
% ; $\gamma = 0.05, \omega = 0.05, E_b / N_0 = \SI{5}{dB}$
\end{itemize}
@ -969,6 +1010,12 @@ return $\boldsymbol{\hat{c}}$
\item For larger $n$, the gradient itself starts to oscillate
\item Dynamic range of oscillation highly correlated with probability of bit error
\end{itemize}
\bigskip
\bigskip
\addreference{Mac23}{David J.C. MacKay: \emph{Encyclopedia of Sparse Graph Codes}.
Jan. 2023. URL: \url{http://www.inference.org.uk/mackay/codes/data.html}.}
\end{frame}
@ -1086,7 +1133,7 @@ return $\boldsymbol{\hat{c}}$
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\begin{frame}[t, fragile]
\frametitle{Proximal Decoding: Improvement using \\``ML-in-the-List''}
\frametitle{Proximal Decoding: Improvement}
\vspace*{-0.5cm}
@ -1147,12 +1194,12 @@ $\textcolor{KITblue}{\textbf{return }\boldsymbol{\hat{c}}_l\text{ with lowest }d
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\begin{frame}[t]
\frametitle{Proximal Decoding: Improvement using \\``ML-in-the-List''}
\frametitle{Proximal Decoding: Improvement}
\vspace{-0.5cm}
\vspace{-0.6cm}
\begin{itemize}
\item (3,6) regular LDPC code with $n=204, k=102$ \cite[\text{204.33.484}]{mackay_enc}
\item (3,6) regular LDPC code with $n=204, k=102$ \citereference{Mac23, 204.33.484}
\end{itemize}
\begin{figure}[H]
@ -1166,8 +1213,8 @@ $\textcolor{KITblue}{\textbf{return }\boldsymbol{\hat{c}}_l\text{ with lowest }d
legend columns=2,
legend style={at={(0.5,-0.45)},anchor=south},
ymax=1.5, ymin=3e-8,
width=0.48\textwidth,
height=0.33\textwidth,
width=0.45\textwidth,
height=0.3\textwidth,
]
\addplot[ForestGreen, mark=*, line width=1pt]
table [x=SNR, y=BER, col sep=comma, discard if not={gamma}{0.15}]
@ -1199,8 +1246,8 @@ $\textcolor{KITblue}{\textbf{return }\boldsymbol{\hat{c}}_l\text{ with lowest }d
legend columns=2,
legend style={at={(0.5,-0.45)},anchor=south},
ymax=1.5, ymin=3e-8,
width=0.48\textwidth,
height=0.33\textwidth,
width=0.45\textwidth,
height=0.3\textwidth,
]
\addplot[ForestGreen, mark=*, solid, line width=1pt]
@ -1256,6 +1303,11 @@ $\textcolor{KITblue}{\textbf{return }\boldsymbol{\hat{c}}_l\text{ with lowest }d
\begin{itemize}
\item Up to $\sim \SI{1}{dB}$ improvement
\end{itemize}
\bigskip
\addreference{Mac23}{David J.C. MacKay: \emph{Encyclopedia of Sparse Graph Codes}.
Jan. 2023. URL: \url{http://www.inference.org.uk/mackay/codes/data.html}.}
\end{frame}

View File

@ -9,18 +9,37 @@
\begin{frame}[t]
\frametitle{Motivation}
\begin{itemize}
\item The general ML decoding problem is NP-complete \cite{ml_np_hard_proof}
\item The iterative messagepassing algorithms preferred in practice do not guarantee
optimality when the graph contains cycles \cite{ldpc_conv}
\item The standard message-passing algorithms are often difficult to
analyze \cite{feldman_thesis}
\item General ML decoding problem NP-complete \citereference{BMT78}
\item Iterative messagepassing algorithms preferred in practice do not guarantee
optimality when the graph contains cycles \citereference{KTP19}
\item Standard message-passing algorithms difficult to analyze \citereference{FEL03}
\end{itemize}
\vspace{3.5cm}
\addreferences
{BMT78}{E. Berlekamp; R. McEliece; H. van Tilborg: \emph{On the inherent intractability
of certain coding problems (Corresp.)}.
IEEE Transactions on Information Theory 24.3 (May 1978), pp. 384386.}
{KTP19}{Banu Kabakulak; Z. Caner Taşkın; Ali Emre Pusane: \emph{Optimizationbased
decoding algorithms for LDPC convolutional codes in communication systems}.
IISE Transactions 51.10 (2019), pp. 10611074.}
{FEL03}{Jon Feldman: \emph{Decoding error-correcting codes via linear programming}.
PhD thesis. MIT, 2003.}
\stopreferences
\end{frame}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\begin{frame}[t]
\frametitle{Previous Work}
\vspace*{-5mm}
\begin{itemize}
\item Bachelor's thesis by Yanixa Lu \citereference{Lu22}
\end{itemize}
\begin{figure}[h]
\centering
@ -39,14 +58,17 @@
\fbox{\includegraphics[page=60,width=.6\textwidth]{res/Bachelor_Thesis_Yanxia_Lu}}
\end{subfigure}%
\caption{Bachelor's Thesis by Yanxia Lu \cite{yanxia_lu_thesis}}
\end{figure}
\begin{itemize}
\item Analysis of ``Proximal Decoding''
\item Analysis of ``Interior Point Decoding''
\end{itemize}
\bigskip
\addreference{Lu22}{Yanxia Lu: \emph{Realization of Channel Decoding Using Optimization
Techniques}. Bachelors Thesis. KIT, 2022.}
\end{frame}