Polar Code CRC Interleaving for Short-Block Distance Gain
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Solution Overview
Problem
Polar codes with short or medium lengths have insufficient minimum code distance, leading to subpar decoding performance compared to Turbo and LDPC codes.
Innovation Solution
The method involves performing cyclic redundancy check (CRC) coding on information bits, followed by interleaving using a construction parameter-determined interleaver, and then applying polar coding to enhance the minimum code distance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If Polar code is used with short or medium length, then encoding and decoding complexity is reduced, but minimum code distance becomes insufficient and decoding performance deteriorates
Solution Approach 1:
The Polar code is divided into multiple subcodes through code segmentation. Each subcode is encoded and decoded separately, allowing the overall code to achieve better minimum distance properties while maintaining low complexity. The segmentation transforms a single complex code into multiple simpler codes that collectively provide improved performance.
Solution Approach 2:
The invention combines Polar code with other coding techniques to create a composite coding scheme. By integrating multiple coding approaches, the system achieves both the low complexity advantage of Polar codes and the improved minimum distance properties needed for short and medium length codes.
2Reliability
If cascade CRC coding is applied to improve minimum code distance, then decoding performance improves for short/medium codes, but the minimum distance of entire codes cannot be improved under certain generator polynomials
Solution Approach 1:
The invention changes key parameters of the CRC coding, including the generator polynomial selection and the integration method with Polar code. By optimizing these parameters, the system achieves minimum distance improvement across a broader range of code configurations, overcoming the limitations of fixed generator polynomials.
Solution Approach 2:
The invention introduces an interleaver as an intermediary component between the CRC encoder and Polar code encoder. This intermediary element transforms the input bits before Polar encoding, enabling the system to achieve improved minimum distance properties that neither CRC nor Polar code alone can provide, and working effectively with various generator polynomials.
Data Source
AI summary
The present invention provides a coding method and a coding device. The coding method includes: coding information bits a to be coded via cyclic redundancy check CRC, then inputting the bits coded via the CRC into an interleaver determined by a construction parameter of a Polar code, where the interleaver is configured to interleave the bits coded via the CRC and output interleaved bits; and coding the output interleaved bits via the Polar code to obtain a coded Polar code. The above method is used to solve a problem in the prior art that minimum code distance of a Polar code is not large enough when the Polar code is relatively short or is of a medium length.