Jisuanji fangzhen

Simulation of LDPC Decoding Algorithm Based on Channel Estimation

Fang Mei-yan

Published Jan 1, 2007• 0 citations

Abstract

LDPC decoding algorithm on channels with memory is of great significance to high speed digital com- munications.Currently used low-density parity-check codes iterative decoding algorithms on channels with memo- ry,such as Belief-Propagation iterative decoding algorithm based on channel estimation,are commonly complex and thus requiring large amount of calculation.In this paper,a min-sum algorithm is firstly introduced into LDPC itera- tive decoding algorithm based on soft noise decisions and channel estimation on hidden Markov noisy channels.Algo- rithm and calculation complexity are effectively reduced by using the functions'characteristics.Simulation results show that the algorithm not only excels conventional Belief-Propagation iterative decoding algorithms that do not concern channel memory,but also outperforms iterative decoding algorithms based on hard noise decisions and channel esti- mation.So a good compromise is made between decoding performance and algorithm complexity with low performance loss,which is useful real time communications.

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