E-IHRB Decoder Architectures for Non-Binary LDPC Codes

Madamsetti, Kalyani, M, Suseela

Published Aug 31, 2014• 0 citations

Abstract

In the information theory , the non- binary low density parity check (NB-LDPC) code is a linear error correcting code , a method of transmitting message over a noisy transmission channel. LDPCcodes are capacity-approaching codes , which means that practical constructions exist that allow the noise threshold to be set very close to the theoretical maximum for a symmetric memory less channel.Using iterative belief propagation techniques, NB-LDPC codes can be decoded in time linear to their block length. Non-binary low-density parity-check codes can achieve higher performance than their binary counterparts. Recently, two algorithms were developed for decoding NB-LDPC codes: iterative hard reliability-based majority-logic decoding (IHRB-MLGD) and iterative soft reliability-based majority-logic decoding (ISRB-MLGD has better performance-complexity tradeoffs than previous algorithms. This paper first proposes message-passing in such a way that we can reduce the memory consumption to a greater extent at the same time there should not be performance loss. By using enhanced iterative reliability-based majority-logic decoding algorithms we can achieve effective complexity-performance and noise free design. Compared to previous designs, our proposed decoders have at least tens of times lower complexity with moderate coding gain loss.

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