LDPC Code Selection by Parity Length to Reduce Block Errors

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional wireless communication systems using LDPC codes face inefficiencies due to suboptimal performance from rate matching techniques, which restrict final codes to predefined mother codes, leading to reduced performance and increased block-error rates.

Innovation Solution

A method for selecting the best candidate parity encoding code by evaluating target and offered parity encoding properties, involving comparison of information block lengths and parity bits, with options for puncturing or repetition to match target parity bits, thereby optimizing LDPC code selection for specific block lengths and rates.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If rate matching techniques are used to adapt predefined mother codes, then the system can support various block lengths and code rates, but the performance is suboptimal and block-error rates increase

Engineering Contradiction:
Improvesupport for various block lengths and code ratesVSAvoidblock-error rate
Core Design Contradiction:
Adaptability or versatilityVSReliability

Solution Approach 1:

The patent changes the selection criterion from matching code rate to matching parity bit length. By selecting the mother code whose parity bit length is closest to the target parity bit length, the system achieves better performance while maintaining adaptability. This parameter change resolves the contradiction by optimizing the selection process to minimize performance degradation from rate matching.

Inventive Principle:
Principle #35Parameter changes

2Adaptability or versatility

If multiple predefined mother codes are used for different block lengths and code rates, then code adaptability is improved, but device complexity increases

Engineering Contradiction:
Improvecode rate and block length adaptationVSAvoidnumber of predefined mother codes
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent changes the selection approach from maintaining multiple specialized codes to selecting from mother codes based on parity bit length proximity. This reduces the need for extensive code collections while maintaining adaptability through intelligent selection and rate matching techniques.

Inventive Principle:
Principle #35Parameter changes

3Ease of manufacture

If conventional mother code selection is used, then implementation is simplified, but encoding performance is reduced

Engineering Contradiction:
Improveimplementation simplicityVSAvoidencoding performance
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

The patent introduces a feedback mechanism where the target parity bit length is calculated based on desired code rate and block length, then used to select the optimal mother code. This feedback loop ensures that the selected mother code best matches the transmission requirements, improving performance while maintaining implementation feasibility through systematic selection criteria.

Inventive Principle:
Principle #23Feedback

Data Source

PatentEP3497796B1Selection of an error correcting code based on a target information length and a target parity length
Publication Date: 2022.10.26 TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)
  • EP3497796B1 patent drawingFigure 1
  • EP3497796B1 patent drawingFigure 2
  • EP3497796B1 patent drawingFigure 3

AI summary

The disclosure relates to a first wireless node for a wireless communication system, the wireless node comprising processing means operative to obtain input data, a set of target parity encoding properties for the input data and a set of predetermined parity encoding codes each having a set of offered parity encoding properties, obtain a candidate parity encoding code from the set of predetermined parity encoding codes by evaluating a set of criteria on the set of target parity encoding properties and the sets of offered parity encoding properties, wherein evaluating the set of criteria comprises comparing a target information block length and a target number of encoding parity bits, comprised in the target parity encoding properties, to an offered information block length and an offered number of encoding parity bits, comprised in the offered parity encoding properties, and generate transmission data by encoding the input data using the candidate parity encoding code. The disclosure further relates to a method thereof, a computer program, a computer program product and a carrier.