Polar HARQ Retransmission Using Check Bits to Cut Decoding Load
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Solution Overview
Problem
Current incremental redundancy HARQ methods for polar codes in 5G wireless communications face high storage overheads and decoding complexity as the number of retransmissions increases, due to the continuous increase in code length of the combined long code.
Innovation Solution
The method involves determining the reliability of extension bit locations and performing check encoding on information bits, followed by polar encoding and rate matching to optimize the codeword for retransmission, reducing decoding complexity and storage overheads by selecting a reliable decoding path.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If incremental redundancy HARQ is used for polar codes, then data transmission reliability is improved, but storage overheads and decoding complexity increase continuously as retransmission times increase
Solution Approach 1:
The patent segments the code into information bits and check bits, where check bits are used for verification without requiring full decoding of the entire code. This segmentation allows the receiver to validate received data using only the check bits, reducing the computational burden of decoding complex polar codes during retransmissions.
Solution Approach 2:
The patent extracts and utilizes check bits separately from the information bits. By taking out the check bits and using them for independent verification through check decoding, the system avoids the need to perform full polar code decoding on every retransmission, thereby reducing decoding complexity while maintaining reliability.
2Reliability
If incremental redundancy HARQ is used for polar codes, then data transmission reliability is improved, but storage overheads increase continuously as retransmission times increase
Solution Approach 1:
The patent extracts check bits from the polar code structure and uses them for independent verification. This extraction allows the system to validate received packets without storing and processing the entire increasing code length, thereby reducing storage overheads while maintaining transmission reliability.
Solution Approach 2:
The patent uses check bits as a simplified copy or representation of the entire code for verification purposes. Instead of storing and decoding the full polar code which grows with each retransmission, the system uses the compact check bits to verify data integrity, significantly reducing storage requirements.
Data Source
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AI summary
This application provides a data retransmission method and apparatus. The method includes: A transmitting device obtains information to be transmitted for a tth time, where the information to be transmitted for the tth time includes Rt extension locations and information to be transmitted for a (t-1)th time, and the extension locations include Mt information bits and Lt check bits corresponding to the Mt information bits. The transmitting device then performs Polar encoding on the information to be transmitted for the tth time, to obtain a codeword after the Polar encoding, obtains a codeword for (t-1)th retransmission based on the codeword after the Polar encoding, and transmits the codeword for (t-1)th retransmission. A receiving device performs polar decoding after receiving the codeword for (t-1)th retransmission, to obtain a decoding result of codewords for t times of transmission. By performing, on an encoding side, check encoding on the information bits in an extension part, a decoding path can be reduced in a decoding process, thereby greatly reducing decoding complexity, and reducing storage overheads and calculation overheads.