IEEE Transactions on Circuits & Systems II Express Briefs

Efficient Implementation of a Threshold Modified Min-Sum Algorithm for LDPC Decoders

Yanfang Liu, Wei Tang, David G. M. Mitchell

Published Jun 11, 2020• 18 citations

Abstract

In this brief, we present a hardware efficient implementation of a threshold modified min-sum algorithm (MSA) to improve the performance of a low density parity-check (LDPC) decoder. The proposed architecture introduces a novel lookup table based threshold attenuation technique, called threshold attenuated MSA (TAMSA). The proposed TAMSA implementation is shown to improve bit error rate (BER) performance compared to the conventional AMSA and MSA. Furthermore, a layered version of the TAMSA implementation is investigated to reduce hardware cost. Utilizing circuit optimization techniques, including a parallel computing structure, the proposed layered TAMSA field-programmable gate array (FPGA) implementation results show that the modified architecture requires no extra circuit power or circuit area compared to conventional AMSA, and only 0.07% extra leaf cells compared to conventional MSA.

DOI: 10.1109/tcsii.2020.3001601

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