Results 221 to 230 of about 3,456 (247)

Probabilistic analysis of cycles in random Tanner graphs

2013 IEEE International Conference on Signal Processing, Communication and Computing (ICSPCC 2013), 2013
Cycles in bipartite graphs (also called Tanner graphs in channel coding field) are of particular interest in modern coding theory, especially in capacity-achieving low-density parity-check (LDPC) codes. In this paper, the expected number of cycles of various lengths in randomly constructed regular and irregular Tanner graphs are calculated. For a given
Xiaopeng Jiao, Jianjun Mu
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Tanner graphs for group block codes and lattices: construction and complexity

IEEE Transactions on Information Theory, 2001
Summary: We develop a Tanner graph (TG) construction for an Abelian group block code \(L\) with arbitrary alphabets at different coordinates, an important application of which is the representation of the label code of a lattice. The construction is based on the modular linear constraints imposed on the code symbols by a set of generators for the dual ...
Amir H. Banihashemi, Frank R. Kschischang   +1 more
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Generating random Tanner-graphs with large girth

2009 IEEE Information Theory Workshop, 2009
We present a simple and efficient algorithm for randomly generating Tanner-graphs with given symbol-node and check-node degrees and without small cycles. These graphs can be used to design high performance Low-Density Parity-Check (LDPC) codes. Our algorithm generates a graph by sequentially adding the edges to an empty graph.
Mohsen Bayati, Raghunandan Keshavan, Andrea Montanari, Sewoong Oh, Amin Saberi   +4 more
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Analysis of practical LDPC decoders in tanner graphs with absorbing sets

2017 IEEE Information Theory Workshop (ITW), 2017
Abstract--Absorbing sets (ASs) cause the error floor phenomenon in many Low-Density Parity-Check (LDPC) codes. A recent, simplified system model for Min-Sum (MS) LDPC decoding [1] predicts that ASs exhibit a threshold behavior: if all variable nodes in an AS have channel messages above the threshold, the AS cannot trap the decoder.
Marco Ferrari, Alessandro Tomasoni, Sandro Bellini   +2 more
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Girth of the Tanner graph and error correction capability of LDPC codes

2008 46th Annual Allerton Conference on Communication, Control, and Computing, 2008
We investigate the relation between the girth and the guaranteed error correction capability of gamma-left regular LDPC codes. For column-weight-three codes, we give upper and lower bounds on the number of errors correctable by the Gallager A algorithm.
Shashi Kiran Chilappagari, Dung Viet Nguyen, Bane Vasic, Michael W. Marcellin   +3 more
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On the Performance of Tanner Graph Based and Viterbi Decoding for Erasure Recovery

2015 IEEE 82nd Vehicular Technology Conference (VTC2015-Fall), 2015
We address the utilization of short erasure correcting codes to recover the erased data in opportunistic spectrum access (OSA) due to collisions among multiple users. The main application of using short codes over long codes is to avoid long delays in the network.
Muhammad Moazam Azeem, Abdul Baqi Khan, Uzma Azeem   +2 more
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Irregular progressive edge-growth (PEG) Tanner graphs

Proceedings IEEE International Symposium on Information Theory,, 2003
A general method for constructing Tanner graphs having a large girth by progressively establishing edges between symbol and check nodes in an edge-by-edge manner, called progressive edge-growth (PEG) construction, is proposed. Such an approach is powerful for generating good regular and irregular LDPC codes of short and moderate block lengths.
null Xiao-Yu Hu, E. Eleftheriou, D.-M. Arnold   +2 more
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Construction of LDPC Codes with Cycles Hold in Tanner Graph

2007 International Conference on Wireless Communications, Networking and Mobile Computing, 2007
This paper presents a algebraic method for constructing LDPC codes. It uses a parity-check matrix of a short LDPC code with given degree distribution as mother matrix, upon which a long LDPC code is constructed by circulant permutation matrices. The number of cycles of given length in the Tanner graph of constructed codes is equal to or less than that ...
Binbin Liu, Shunliang Mei, Dong Bai
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Codes that have tanner graphs with non-overlapping cycles

2008 5th International Symposium on Turbo Codes and Related Topics, 2008
The sum-product algorithm (SPA) for the decoding of low density parity check (LDPC) codes produces exact posterior probabilities when the underlying Tanner graph is cycle-free. However, it has been shown that cycle-free Tanner graphs cannot support good codes as they have poor minimum distance properties.
S. Srimathy, Andrew Thangaraj
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Which codes have cycle-free Tanner graphs?

IEEE Transactions on Information Theory, 1999
Summary: If a linear block code \(C\) of length \(n\) has a Tanner graph without cycles, then maximum-likelihood soft-decision decoding of \(C\) can be achieved in time \(O(n^2)\). However, we show that cycle-free Tanner graphs cannot support good codes. Specifically, let \(C\) be an \((n, k,d)\) linear code of rate \(R=k/n\) that can be represented by
Tuvi Etzion, Ari Trachtenberg, Alexander Vardy   +2 more
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