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IEEE Communications Letters

Reliability-Based Iterative Decoding of LDPC Codes Using Likelihood Accumulation

Ming Yan Jiang, Chunming Zhao, Enyang Xu, Li Guo Zhang

Published Aug 1, 2007• 38 citations
Publisher

Abstract

In this work, we present an improvement on low complexity serial concatenation of belief propagation (BP) - order statistic decoding (OSD) algorithm for low-density parity-check (LDPC) codes. We introduce a more reliable method to reconstruct ordered information sequence in terms of the accumulated log-likelihood ratio (LLR) transitions of variable nodes. We give a general expression for both the existing BP-OSD algorithm and our proposed new method according to a structure similar to an infinite impulse response (IIR) filter. This improved algorithm achieves noticeable performance gains with only modest increase in computation complexity.

DOI
10.1109/lcomm.2007.070450

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This paper analyses the ordered statistic decoding(OSD) algorithm of short LDPC codes and investigates BP-OSD concatenation algorithm and LLR accumulation algorithm.Considering the tradeoff between the complexity and performance of decoding,the min-sum algorithm was used instead of the BP algorithm,and it was concatenated with LLR accumulation algorithm.Simulation results show that compared with the original BP algorithm,the performance of the improved concatenation algorithm has been greatly raised,and compared with the BP-OSD concatenation algorithm,its decoding complexity has been reduced and the performance is nearly the same.
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