Design and Performance of Rate-compatible Non-Binary LDPC Convolutional Codes

TL;DR

This paper introduces a construction method for non-binary LDPC convolutional codes, demonstrating their rate-compatibility and superior performance over binary counterparts in simulations.

Contribution

It extends Felstroem and Zigangirov's construction to non-binary codes and explores rate-compatibility through puncturing and repetition techniques.

Findings

Non-binary LDPC convolutional codes outperform binary codes at similar constraint lengths.

Rate-compatibility achieved via puncturing and repetition maintains good performance.

Codes exhibit small gaps to Shannon limits across various rates.

Abstract

In this paper, we present a construction method of non-binary low-density parity-check (LDPC) convolutional codes. Our construction method is an extension of Felstroem and Zigangirov construction for non-binary LDPC convolutional codes. The rate-compatibility of the non-binary convolutional code is also discussed. The proposed rate-compatible code is designed from one single mother (2,4)-regular non-binary LDPC convolutional code of rate 1/2. Higher-rate codes are produced by puncturing the mother code and lower-rate codes are produced by multiplicatively repeating the mother code. Simulation results show that non-binary LDPC convolutional codes of rate 1/2 outperform state-of-the-art binary LDPC convolutional codes with comparable constraint bit length. Also the derived low-rate and high-rate non-binary LDPC convolutional codes exhibit good decoding performance without loss of large gap to the Shannon limits.