Multi-Rate LDPC Encoding with Base-Code Rate Adaptation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional LDPC codes have high-density generator matrices, making encoding computationally intensive and impractical for many applications, and constructing LDPC codes with different code rates is challenging.
Innovation Solution
The development of multi-rate low-density parity check (LDPC) codes with different code rates, utilizing a base LDPC code and permutation patterns to optimize encoding, allowing for flexible code rate adjustments and improved encoding efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional LDPC codes with high-density generator matrices are used, then error correction capability is maintained, but encoding computational complexity increases significantly
Solution Approach 1:
The patent segments the encoding process by separating information bits from parity bit generation. The high-density generator matrix is decomposed into systematic form where parity bits are generated independently through matrix-vector multiplication with the parity check matrix, reducing the encoding complexity while maintaining error correction capability.
Solution Approach 2:
The patent changes the parameter representation from high-density generator matrices to low-density parity check matrices. This parameter transformation allows the same error correction code to be implemented with significantly reduced computational complexity by exploiting the sparse structure of the parity check matrix.
2Reliability
If LDPC codes are designed for specific code rates, then error correction performance is optimized, but adaptability to different code rates decreases
Solution Approach 1:
The patent creates a universal LDPC code structure that can operate at multiple code rates by using a base parity check matrix that supports systematic encoding. The same encoder framework can generate codes with different code rates by adjusting the information bit length and corresponding parity bit generation, making the system multi-functional across different communication requirements.
Solution Approach 2:
The patent introduces dynamic adaptability by allowing the encoder to adjust the number of information bits and corresponding parity bits based on the desired code rate. The systematic encoding structure enables dynamic configuration of code parameters while maintaining the underlying low-density parity check structure, providing flexibility for different transmission conditions.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An apparatus (105) may include a transmitter (120). The apparatus (105) may identify a target code rate and a low density parity check, LDPC, code that has a base code rate for a base size of information bits, select, based at least on the target data rate and the base code rate, a first size that is less than the base size of information bits, generate a second set of information bits to include a first set of information bits corresponding to the first size and one or more bits to increase a size of the second set of information to correspond to the base size of information bits, encode, using the base code rate, the second set of information bits to generate parity data, and generate a codeword by concatenating the first set of information bits and the parity data to achieve the target code rate. The transmitter (120) may transmit the codeword.