Polar Code Decoding with Reliable-Bit Path Splitting Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Polar codes exhibit high decoding complexity, particularly in short or moderate code lengths, which hinders their performance compared to Turbo codes and LDPC codes, and error propagation during successive-cancellation decoding degrades decoding performance.
Innovation Solution
A method and device for decoding Polar codes that identify a reliable subset of information bits with higher reliability, allowing judgment and modification of decoding paths without splitting, thereby reducing overall decoding complexity and maintaining performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If SC-List decoding is used to maintain multiple candidate paths and achieve decoding performance approaching maximum likelihood, then decoding performance is improved, but decoding complexity increases to O(L×N×log2 N), which is about L times the complexity of SC decoding
Solution Approach 1:
The patent segments the information bit set into a reliable subset and an unreliable subset based on bit reliability metrics. For bits in the reliable subset, the decoder performs judgment without path splitting, while for bits in the unreliable subset, path splitting is performed. This segmentation allows the system to achieve near-maximum-likelihood performance for reliable bits with reduced complexity, while maintaining overall decoding performance through selective path splitting only where necessary.
2Device complexity
If successive-cancellation decoding is performed in order of bits with hard judgment for each decoded bit, then decoding complexity is reduced to O(N log2 N), but error propagation occurs resulting in degradation of decoding performance
Solution Approach 1:
The patent applies local quality by treating different bits differently based on their reliability characteristics. High-reliability bits in the reliable subset are decoded with simple judgment (similar to SC decoding), while low-reliability bits in the unreliable subset undergo path splitting (similar to List decoding). This localized differentiation allows the system to minimize error propagation for reliable bits while maintaining acceptable complexity, thereby improving overall decoding performance without uniformly increasing complexity across all bits.
Data Source
AI summary
Embodiments of the present invention provide a method and a device for decoding Polar codes. A reliable subset is extracted from an information bit set of the Polar codes, where reliability of information bits in the reliable subset is higher than reliability of other information bits. The method includes: obtaining a probability value or an LLR of a current decoding bit of the Polar codes; when the current decoding bit belongs to the reliable subset, performing judgment according to the probability value or the LLR of the current decoding bit to determine a decoding value of the current decoding bit, keeping the number of decoding paths of the Polar codes unchanged, and modifying probability values of all the decoding paths by using the probability value or the LLR of the current decoding bit.