Journal of Zhejiang University(Engineering Science)

Improved decoding approach of low-density parity-check codes with finite precision

Kuang Wang

Published Jan 1, 2008• 0 citations

Abstract

An improved parallel decoding approach of sum-product algorithm for low-density parity-check codes(LDPC) was presented in order to solve the problem of divergence in decoding iteration with finite precision,.In addition,the reason for improving the convergence speed was discussed detailedly and the pipeline structure was provided.By eliminating the unexpected state in which operation data didn't satisfy input rules due to the finite precision effect thus could not be preceded correctly,the iteration convergence was improved efficiently and led to decoding with no error.Compared with the original parallel approach,this improvement don't involve too much control logic and computational complexity.Simulation shows that the proposed decoding approach over additive white Gaussian noise(AWGN) channel achieves good performance,especially at high code rate,it suffers negligible performance loss compared with the forward-backward approach while reducing the operation complexity effectively.

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