LDPC Code Block Segmentation by Base Graph Selection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current communication systems face challenges in efficiently segmenting transport blocks for data channel coding, particularly in LTE and 5G systems, due to limitations in code block segmentation and error correction mechanisms, which affect data reliability and throughput.
Innovation Solution
The method involves selecting an appropriate LDPC base matrix based on code rate and transport block size, determining the number of code blocks, calculating each code block's size, segmenting the transport block, padding zeros, attaching code block-level CRC bits, encoding each segment using the selected LDPC base graph, and transmitting the encoded blocks.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If transport blocks are segmented into code blocks for LDPC encoding, then error correction capability is improved, but system complexity increases due to multiple segmentation schemes
Solution Approach 1:
The patent changes the parameter of base matrix selection (from fixed to variable based on code rate) to optimize segmentation. By selecting different base matrices according to code rate ranges, the system adapts segmentation parameters dynamically, improving error correction while managing complexity through standardized selection criteria.
Solution Approach 2:
The patent segments the transport block into multiple code blocks for parallel LDPC encoding. This segmentation improves reliability by enabling independent error correction for each code block, while the use of a determined number of code blocks based on base matrix selection prevents excessive segmentation complexity.
2Adaptability or versatility
If multiple base matrices are supported for different code rates, then adaptability to varying code rates is improved, but device complexity increases
Solution Approach 1:
The patent implements parameter changes by selecting different base matrices based on code rate ranges. The system supports multiple base matrices (first base matrix for lower code rates, second base matrix for higher code rates) and dynamically selects among them based on the actual code rate, achieving code rate adaptability while maintaining manageable complexity through clear selection rules.
Solution Approach 2:
The patent introduces dynamics by making base matrix selection variable rather than fixed. The system adapts its configuration in real-time based on code rate conditions, switching between different base matrices to optimize performance for varying code rates without requiring complex manual configuration.
3Productivity
If code block segmentation is optimized for specific base matrices, then encoding efficiency is improved, but flexibility across different code rates decreases
Solution Approach 1:
The patent resolves this contradiction by making base matrix selection a variable parameter dependent on code rate. For code rates below a threshold, the first base matrix is selected with its optimized segmentation scheme; for code rates at or above the threshold, the second base matrix is selected. This parameter change approach maintains encoding efficiency for each code rate range while providing overall flexibility across different code rates.
Data Source
AI summary
An apparatus and method are described. The apparatus includes a transceiver and processor, which attach transport block (TB) level CRC bits to a TB, select an LDPC base graph (BG) based on a code rate (CR) and TB size of the TB including TB level CRC bits, determine a number of code blocks (CBs) to use for segmenting the TB including TB level CRC bits depending on the selected LDPC BG, determine a single CB size for each of the CBs based on the number of CBs, segment the TB including TB level CRC bits into the CBs based on the number of CBs and CB size, pad zeros to a last CB of the CBs in the segmented TB, attach CB level CRC bits to each CB in the segmented TB, encode each CB in the segmented TB using the selected LDPC base graph, and transmit the encoded CBs.