Self-Connected Spatially Coupled LDPC Codes with Improved Termination

TL;DR

This paper introduces self-connected spatially coupled LDPC codes with a novel termination method that reduces rate loss and enhances decoding performance, achieving better capacity gap and threshold saturation.

Contribution

It proposes a new self-connection and termination approach for SC-LDPC codes, improving rate efficiency and decoding thresholds compared to existing designs.

Findings

Reduced rate loss with single-side open ensemble

Improved decoding threshold and capacity gap

Finite blocklength performance demonstrates superiority

Abstract

This paper investigates the design of self-connected spatially coupled low-density parity-check (SC-LDPC) codes. First, a termination method is proposed to reduce rate loss. Particularly, a single-side open SC-LDPC ensemble is introduced, which halves the rate loss of a conventional terminated SC-LDPC by reducing the number of check nodes. We further propose a self-connection method that allows reliable information to propagate from several directions to improve the decoding threshold. We demonstrate that the proposed ensembles not only achieve a better trade-off between rate loss and gap to capacity than several existing protograph SC-LDPC codes with short chain lengths but also exhibit threshold saturation behavior. Finite blocklength error performance is provided to exemplify the superiority of the proposed codes over conventional protograph SC-LDPC codes.