Soft information boosts hard-decision decoding for product-like codes

Four-Level Quantized Soft Information Aided Hard-Decision Decoder for Product-like Codes

Information Theory

Summary

Digital communications often use codes to detect and fix errors, but decoding them can be complex or error-prone. This paper introduces a method that combines simple decoding steps with smart use of limited reliability information about each bit to improve error correction. The authors show this method helps fix more errors without a big jump in complexity. Their tests confirm better performance than traditional approaches and match methods needing more detailed information.

What this means in practice

Authors

Xiaowei Wu, Min Qiu, Yueying Zhan, Lei Yang

Abstract

We propose a novel low-complexity soft-aided hard-decision decoding scheme for product-like codes, termed iterative bounded-distance decoding (iBDD) with graded scaled reliability and bit-flipping (GSRF). This scheme operates on four-level quantized soft information. It incorporates a graded scaled reliability rule to assign decoding confidence to the bounded-distance decoding result, and employs a bit-flipping rule based on bit-level and component-code-level reliability. A selective re-decoding rule is designed to further facilitate the error performance while keeping the number of BDD attempts in reasonably low levels. The decoding parameter design of iBDD-GSRF is investigated for product codes and staircase codes, respectively. Simulation results on both codes verify that iBDD-GSRF achieves a gain of more than 0.4 dB over the conventional iBDD, comparable to several existing unquantized soft-aided decoders.