QC-LDPC Shift Coefficient Tables for 5G NR Lifting Factors

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Solution Overview

Problem

The specifics of quasi-cyclic low-density parity-check (QC-LDPC) coding and decoding for 5G NR wireless communications are not yet defined, particularly in terms of shift coefficient and lifting factor design, which is crucial for next-generation communications.

Innovation Solution

A method involving a processor that generates QC-LDPC codes by defining sets of lifting factors, generating shift values for each using a nested design with mod operations, and constructing the QC-LDPC code using a base matrix and shift coefficient table, enabling efficient encoding and decoding.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If multiple sets of lifting factors are defined with nested design and mod operations, then the adaptability and versatility of QC-LDPC codes for different code rates and block lengths is improved, but the device complexity and computational overhead increase

Engineering Contradiction:

Improveadaptability of QC-LDPC codesVSAvoidcomplexity of code generation

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The lifting factor is divided into multiple sets (first set, second set, third set, etc.), each corresponding to different code rates and block lengths. This segmentation allows the system to select appropriate lifting factors for specific communication scenarios, improving adaptability while managing complexity through organized categorization.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

A nested design is employed where inner lift values and outer lift values are combined through mod operations to generate comprehensive shift coefficient tables. The nested structure allows efficient representation of multiple lifting factor sets, reducing the overall complexity by organizing parameters in hierarchical relationships.

Inventive Principle:

Principle #7Nested doll (Nesting)

Solution Approach 3:

Different lifting factors from multiple sets are selected and applied based on specific code rate and block length requirements. By changing the lifting factor parameter dynamically, the system adapts to different communication scenarios without requiring complete redesign of the coding scheme.

Inventive Principle:

Principle #35Parameter changes

2Reliability

If comprehensive shift coefficient tables are generated for multiple lifting factors, then the reliability and performance of data transmission is improved, but the memory requirements and processing time increase

Engineering Contradiction:

Improvedata transmission reliabilityVSAvoidcode generation time

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

Comprehensive shift coefficient tables are pre-generated and stored for multiple lifting factors before actual data transmission. This preliminary preparation ensures that during real-time communication, the appropriate shift coefficients can be quickly retrieved and applied, improving transmission reliability without adding significant processing delay.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The shift coefficient tables are designed to be universal and applicable across multiple lifting factor sets. A single comprehensive table structure can serve multiple code rates and block lengths, reducing the need for separate tables and minimizing memory requirements while maintaining reliability.

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Productivity

If nested design with mod operations is used to represent shift coefficients, then the efficiency of encoding and decoding processes is improved, but the difficulty of implementation and debugging increases

Engineering Contradiction:

Improveencoding efficiencyVSAvoidimplementation difficulty

Core Design Contradiction:

ProductivityVSDifficulty of detecting and measuring

Solution Approach 1:

Mod operations serve as intermediaries that bridge the nested design structure and the final shift coefficient values. These mod operations simplify the relationship between inner and outer lift values, making the implementation more systematic and easier to debug by providing clear mathematical relationships between parameters.

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentUS10581457B2Shift coefficient and lifting factor design for NR LDPC code

Publication Date: 2020.03.03 MEDIATEK INC

AI summary

Concepts and schemes pertaining to shift coefficient and lifting factor design for NR LDPC code are described. A processor of an apparatus may generate a quasi-cyclic-low-density parity-check (QC-LDPC) code and encode data using the selected codebook. In generating the QC-LDPC code, the processor may define a plurality of sets of lifting factors, generate a respective table of shift values for each lifting factor of the plurality of sets of lifting factors, and generate the QC-LDPC code using a base matrix and the shift coefficient table.