International Conference on Intelligent Computation Technology and Automation

Analysis on QC-LDPC Decoding Algorithms for WLAN Systems

Xin Lu, Zhan Shaobin, Xu Jiong

Published May 1, 2010• 2 citations

Abstract

Next generation wireless systems, such as IEEE802.11n and 802.16e, need high error-correction capacity to achieve high data rate transmission. Therefore, a low-density parity-check code(LDPC code) is adopted as a FEC code. Quasi-cyclic LDPC code(QC-LDPC) code is an important branch of LDPC code research. IEEE 802.16e proposes a parity-check matrix with quasi-cyclic character which makes the encoding very simply. This paper introduces the encoding process and several decoding algorithms for LDPC including Log-BP algorithm, Min-Sum(MS) algorithm and modified MS algorithm. Simulations results under a next generation wireless LAN system show that MS comparing with the Log-BP performance has approximately 0.5dB loss for high-speed rates codes over AWGN channel, however the performance of normalized MS and row weight matched MS with relatively low complexity is nearly the same as that of Log-BP algorithm.

DOI: 10.1109/icicta.2010.820

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