LDPC Channel Coding with Variable Block Sizes and Coding Rates
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Solution Overview
Problem
Existing LDPC code technologies face challenges in supporting various input lengths and coding rates, particularly in designing parity-check matrices that maintain performance across different lengths and rates, which limits their application in mobile communication systems.
Innovation Solution
The method involves determining a block size for the parity-check matrix, transforming sequences based on this size, generating parity bits, and applying padding to ensure compatibility with various codeword lengths, allowing for LDPC encoding and decoding that supports variable input lengths and coding rates.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a fixed parity-check matrix design is used, then the encoding/decoding process is simple, but it cannot support various input lengths and coding rates
Solution Approach 1:
The input bit sequence is divided into multiple code blocks, each of which can be independently encoded using the same parity-check matrix structure. This allows the system to handle variable input lengths by adjusting the number of code blocks while maintaining a standardized encoding process for each block.
Solution Approach 2:
The parity-check matrix parameters (block size, number of rows, number of columns) are configured based on the input length and desired coding rate. By dynamically adjusting these parameters, the system can support various input lengths and coding rates without requiring completely different matrix designs for each case.
2Ease of operation
If padding bits are added to match fixed block sizes, then encoding is simplified, but transmission efficiency decreases
Solution Approach 1:
The system dynamically determines the number of padding bits based on the actual input length and the configured code block size. Rather than always using fixed padding, the system adjusts the padding amount to minimize waste while ensuring that each code block meets the encoding requirements.
Solution Approach 2:
The code block size parameter is configured to balance between encoding simplicity and transmission efficiency. By optimizing this parameter based on typical input characteristics, the system reduces the average amount of padding required while maintaining the simplicity of fixed-block encoding.
3Reliability
If different parity-check matrices are designed for different code lengths, then performance is optimized for each length, but system complexity increases significantly
Solution Approach 1:
A single parity-check matrix design is created that can serve multiple code lengths through parameter configuration. The matrix is designed with a structure that allows it to function effectively for various input lengths and coding rates, eliminating the need for separate optimized matrices for each case.
Solution Approach 2:
The parity-check matrix parameters are configured based on the desired code length and coding rate. By changing parameters such as the number of rows, columns, and block size, the same fundamental matrix structure can be adapted to provide good error correction performance for multiple different code lengths without requiring completely different designs.
Data Source
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AI summary
The present invention related to a 5G or pre-5G communication system to be provided to support a higher data transmission rate since 4G communication systems like LTE. The present invention relates to a method and an apparatus for encoding a channel in a communication or broadcasting system supporting parity-check matrices having various sizes are provided. The method for a channel coding performed by an apparatus in a wireless communication system, the method comprising: identifying, using at least one processor of the apparatus, a number of input bits; identifying, using the at least one processor of the apparatus, a number of code blocks based on the number of the input bits and a maximum number of information bits corresponding to a largest parity-check matrix; identifying, using the at least one processor of the apparatus, a size of a code block based on the number of code blocks; identifying, using the at least one processor of the apparatus, the code block based on at least a part of the input bits and the size of the code block; identifying, using the at least one processor of the apparatus, a parity-check matrix based on the size of the code block; encoding, using an encoder of the apparatus, the code block based at least in part on the parity-check matrix; and transmitting, using a transceiver of the apparatus, at least a part of the encoded code block.