Single-Scan Min-Sum Algorithms for Fast Decoding of LDPC Codes

TL;DR

This paper introduces a single-scan min-sum decoding algorithm for LDPC codes that significantly speeds up decoding and reduces memory and wiring requirements, with a simple implementation and improved performance.

Contribution

It proposes a novel single-scan min-sum algorithm for LDPC decoding, including a binary message version, enhancing speed and efficiency over traditional methods.

Findings

More than twice as fast as the original min-sum algorithm

Reduces memory usage and wiring complexity

Simplifies implementation with binary messages

Abstract

Many implementations for decoding LDPC codes are based on the (normalized/offset) min-sum algorithm due to its satisfactory performance and simplicity in operations. Usually, each iteration of the min-sum algorithm contains two scans, the horizontal scan and the vertical scan. This paper presents a single-scan version of the min-sum algorithm to speed up the decoding process. It can also reduce memory usage or wiring because it only needs the addressing from check nodes to variable nodes while the original min-sum algorithm requires that addressing plus the addressing from variable nodes to check nodes. To cut down memory usage or wiring further, another version of the single-scan min-sum algorithm is presented where the messages of the algorithm are represented by single bit values instead of using fixed point ones. The software implementation has shown that the single-scan min-sum algorithm is more than twice as fast as the original min-sum algorithm.