LDPC Parity-Bit Puncturing Priority for High-Rate Decoding

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing puncturing methods for LDPC codes in wireless communications fail to effectively distinguish parity bits, leading to poor performance of high coding rate LDPC codes, particularly due to random puncturing that does not optimize the puncturing location and order, resulting in inefficient use of system resources and suboptimal decoding performance.

Innovation Solution

A data sending method that determines puncturing priority for each parity bit using row destruction and/or cycle destruction on the LDPC code check matrix, allowing for selective puncturing of parity bits based on their impact on decoding performance, thereby improving the reliability and efficiency of high coding rate LDPC codes.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If random puncturing is used to obtain high rate LDPC codes, then coding rate is improved, but puncturing performance and decoding reliability deteriorate

Engineering Contradiction:
Improvecoding rateVSAvoiddecoding performance
Core Design Contradiction:
Adaptability or versatilityVSReliability

Solution Approach 1:

The patent applies local quality by differentiating the puncturing process based on variable node degrees. Instead of uniform random puncturing, the method selectively punctures parity bits associated with variable nodes of degree 2 while preserving those associated with variable nodes of degree 3. This localized differentiation in puncturing strategy optimizes decoding performance by maintaining critical check equations while achieving the desired coding rate.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent changes the puncturing parameter from random selection to degree-based selective selection. By modifying the puncturing criterion to consider variable node degrees, the method transforms the puncturing process from a random operation to a structured operation that preserves decoding reliability while achieving high coding rates.

Inventive Principle:
Principle #35Parameter changes

2Ease of manufacture

If random puncturing is used, then implementation simplicity is maintained, but puncturing location optimization is lost

Engineering Contradiction:
Improveimplementation simplicityVSAvoidpuncturing location optimization
Core Design Contradiction:
Ease of manufactureVSManufacturing precision

Solution Approach 1:

The patent applies preliminary action by pre-classifying variable nodes into degree 2 and degree 3 categories before the puncturing process. The method预先 identifies which variable nodes have degree 2 and which have degree 3, then uses this pre-established classification to guide the puncturing selection. This preliminary classification enables optimized puncturing location selection without requiring complex real-time computations during the puncturing process.

Inventive Principle:
Principle #10Preliminary action

3Reliability

If degree-based puncturing is used to improve performance, then decoding reliability is improved, but parity bit distinction capability deteriorates

Engineering Contradiction:
Improvedecoding reliabilityVSAvoidparity bit distinction capability
Core Design Contradiction:
ReliabilityVSMeasurement precision

Solution Approach 1:

The patent resolves this contradiction by applying local quality through differentiated treatment of parity bits based on their associated variable node degrees. Instead of treating all parity bits uniformly, the method identifies and selectively punctures only those parity bits associated with degree 2 variable nodes, while preserving parity bits associated with degree 3 variable nodes. This localized distinction maintains both decoding reliability and parity bit distinction capability.

Inventive Principle:
Principle #3Local quality

Data Source

PatentEP3131219B1Puncturing of LDPC codes
Publication Date: 2023.11.15 HUAWEI TECH CO LTD
  • EP3131219B1 patent drawingFigure 1~2
  • EP3131219B1 patent drawingFigure 3~4
  • EP3131219B1 patent drawingFigure 5~6

AI summary

The present invention discloses a data sending method and apparatus, which resolves a problem that performance of a high coding rate LDPC code obtained in an existing puncturing manner based on a variable node degree distribution is relatively poor because in the puncturing manner, to-be-punctured parity bits that use LDPC codes cannot be effectively distinguished. The method includes: encoding, by using an LDPC code check matrix, an information bit that needs to be sent, to obtain a codeword sequence; determining a puncturing priority of each parity bit in the codeword sequence according to row destruction and/or cycle destruction, on the LDPC code check matrix, of a variable node corresponding to each parity bit; puncturing the codeword sequence according to the puncturing priority of each parity bit in the codeword sequence; and generating a bit sequence according to the punctured codeword sequence, and sending the bit sequence. In this way, performance of an obtained high coding rate LDPC code is improved.