QC-LDPC Base Matrix Layout for High-Speed Layered Decoding

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Solution Overview

Problem

Existing LDPC decoding and encoding methods face inefficiencies due to long waiting times and complex hardware requirements, particularly in high-bit-rate scenarios where layered decoding is used.

Innovation Solution

The proposed solution involves determining a basic matrix with specific up-and-down adjacent pairs for LDPC encoding and decoding, allowing for high pipeline speed and reducing the need for complex hardware, such as inverse cyclic shift networks.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional layered decoding is used for LDPC codes, then decoding capability is achieved, but long waiting times occur and hardware complexity increases

Engineering Contradiction:
Improvedecoding capabilityVSAvoidwaiting time
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The patent segments the basic matrix into multiple sub-matrices arranged in a specific structure with up-and-down adjacent pairs. This segmentation allows the decoding process to be divided into independent parallel operations, eliminating long waiting times while maintaining decoding capability through the structured arrangement of sub-matrices.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent introduces a new structural dimension by organizing sub-matrices in a two-dimensional array with specific up-and-down adjacent pair relationships. This dimensional organization enables parallel processing across multiple dimensions, reducing waiting time while preserving the decoding capability through the structured matrix arrangement.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Reliability

If conventional LDPC encoding and decoding hardware is implemented, then encoding and decoding functions are achieved, but hardware complexity increases

Engineering Contradiction:
Improveencoding and decoding functionVSAvoidhardware complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The basic matrix is segmented into multiple sub-matrices that can be processed independently. This segmentation reduces hardware complexity by allowing modular implementation where each sub-matrix can be handled by simpler, dedicated hardware units rather than requiring complex universal processing units.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The structured basic matrix with up-and-down adjacent pairs enables a single hardware unit to perform multiple functions by processing different sub-matrices in sequence or parallel. This multi-functionality reduces overall hardware complexity while maintaining complete encoding and decoding capabilities.

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Productivity

If high pipeline speed is achieved through optimized basic matrix structure, then encoding and decoding efficiency is improved, but hardware complexity may increase

Engineering Contradiction:
Improveencoding and decoding efficiencyVSAvoidhardware complexity
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The basic matrix is divided into sub-matrices arranged in a structured pattern with up-and-down adjacent pairs. This segmentation enables high pipeline speed by allowing parallel processing of multiple sub-matrices simultaneously, improving encoding and decoding efficiency without requiring overly complex hardware since each sub-matrix can be processed by simple, identical units.

Inventive Principle:
Principle #1Segmentation

Data Source

PatentEP3799313B1Encoding method, decoding method, encoding device and decoding device for structured QC-LDPC codes
Publication Date: 2025.05.28 ZTE CORP
  • EP3799313B1 patent drawingFigure 1~3
  • EP3799313B1 patent drawingFigure 4~6
  • EP3799313B1 patent drawingFigure 7~9

AI summary

An encoding method, decoding method, encoding device and decoding device for structured LDPC codes. The method includes: determining a base matrix used for encoding, which includes K0 up-and-down adjacent pairs; and according to the base matrix and an expansion factor corresponding to the base matrix, performing an LDPC encoding operation of obtaining a codeword of Nb×z bits according to source data of (Nb-Mb)×z bits, herein z is the expansion factor, and z is a positive integer which is greater than or equal to 1. The provided technical solution is applicable to the encoding and decoding of the structured LDPC, thereby realizing the encoding and layered decoding of LDPC at the high pipeline speed.