Block LDPC Parity-Check Matrix Layout for Longer Factor-Graph Cycles
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current LDPC codes in mobile communication systems face challenges in maximizing error correction capability, minimizing coding complexity, and optimizing cycle length in factor graphs, leading to performance degradation and high coding complexity.
Innovation Solution
A method for generating a parity check matrix for block LDPC codes that maximizes minimum cycle length, optimizes degree distribution, and minimizes coding complexity by dividing the matrix into information and parity parts, using permutation matrices and identity matrices to ensure efficient encoding and decoding processes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If LDPC codes are used for error correction in mobile communication systems, then error correction capability is improved, but coding complexity increases
Solution Approach 1:
The parity check matrix is divided into multiple blocks, where each block corresponds to a specific degree. This segmentation allows the decoding process to be organized into degree-based stages, reducing the overall coding complexity while maintaining error correction capability.
Solution Approach 2:
The patent applies different decoding strategies to different blocks based on their degree characteristics. High-degree blocks and low-degree blocks are processed differently, optimizing the error correction capability for each local region while managing overall coding complexity.
2Reliability
If permutation matrices are used to maximize minimum cycle length in factor graphs, then error correction capability is improved, but device complexity increases
Solution Approach 1:
The factor graph is segmented into multiple blocks based on degree distribution. By organizing the graph into discrete blocks, the patent makes it feasible to apply permutation matrices systematically to maximize minimum cycle length without overwhelming device complexity.
Solution Approach 2:
The patent changes the structural parameters of the factor graph by introducing permutation matrices in specific blocks. This parameter change increases the minimum cycle length, which improves error correction capability while the block structure controls the complexity increase.
3Reliability
If degree distribution is optimized in the parity check matrix, then error correction capability is improved, but coding complexity increases
Solution Approach 1:
The parity check matrix is segmented into blocks with different degree characteristics. This segmentation enables optimized degree distribution across blocks, improving error correction capability while the modular block structure manages coding complexity.
Solution Approach 2:
Different degree distributions are applied to different blocks locally. High-degree blocks provide strong error correction while low-degree blocks reduce complexity, creating a balanced overall system that optimizes the trade-off between reliability and coding complexity.
Data Source
AI summary
A method for generating a parity check matrix of a block LDPC code. The parity check matrix includes an information part corresponding to an information word and a first parity part and a second parity part each corresponding to a parity. The method includes determining a size of the parity check matrix based on a coding rate applied when coding the information word with the block LDPC code, and a codeword length; dividing a parity check matrix with the determined size into a predetermined number of blocks; classifying the blocks into blocks corresponding to the information part, blocks corresponding to the first parity part, and blocks corresponding to the second parity part; arranging permutation matrixes in predetermined blocks from among the blocks classified as the first parity part, and arranging identity matrixes in a full lower triangular form in predetermined blocks from among the blocks classified as the second parity part; and arranging the permutation matrixes in the blocks classified as the information part such that a minimum cycle length is maximized and weight values are irregular on a factor graph of the block LDPC code.