Bandaoti guangdian

Analysis on a Novel Decoding Algorithm of SCG-LDPC Codes for Optical Transmission Systems

YE Wenwe

Published Jan 1, 2014• 0 citations

Abstract

According to the structural characteristics of SCG-LDPC codes,an effective Hierarchical Reliable Belief Propagation(HRBP)decoding algorithm is proposed.The novel decoding algorithm combines the layered iteration with the reliability judgment and can greatly reduce the number of the variable node involved in the subsequent iteration process and accelerate the convergence rate.The simulation result of SCG-LDPC(3969,3720)code for optical transmission systems shows that the novel HRBP decoding algorithm,compared with the traditional BP algorithm,can highly reduce the computing amount at the condition of ensuring the performance.The bit error rate(BER)performance of the HRBP algorithm is similar to that of the BP algorithm at the threshold value of 15,but in the subsequent iteration process,the number of the variable nodes for the HRBP algorithm,compared with the BP algorithm,can reduce about 69% at the high signal noise ratio(SNR).When the threshold value is further increased,the HRBP algorithm will gradually degenerate into the Layered-BP algorithm.

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