CRC Interleaving Sequence Generation for Low-Delay Channel Coding
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Solution Overview
Problem
In wireless communications systems, the existing distributed CRC encoding methods require significant storage overhead due to the need for large interleaving sequences to support varying information bit quantities, leading to increased encoding delays and resource consumption.
Innovation Solution
The proposed method uses a system-supported maximum-length interleaving sequence and a preset rule to generate an interleaving sequence of appropriate length for distributed CRC encoding, allowing for efficient interleaving operations even when the information bit quantity is less than the maximum, thereby reducing encoding delays and storage requirements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a large interleaving sequence is used to support varying information bit quantities, then the system can handle different information bit quantities, but storage overhead increases significantly
Solution Approach 1:
The interleaving sequence is segmented into multiple parts or segments. Instead of storing one large interleaving sequence that can handle all possible information bit quantities, the system divides the sequence into smaller segments that can be selectively combined or used individually based on the actual information bit quantity, thereby reducing storage overhead while maintaining adaptability.
Solution Approach 2:
The interleaving sequence structure is made dynamic rather than static. The system can adaptively select or generate appropriate interleaving sequences based on the actual information bit quantity, rather than pre-storing all possible sequences. This dynamic approach allows the system to handle varying information bit quantities without requiring storage of all possible large sequences.
2Adaptability or versatility
If a large interleaving sequence is stored to support maximum information bit quantity, then the system can handle maximum capacity, but encoding delay increases
Solution Approach 1:
The large interleaving sequence is divided into smaller segments that can be processed independently and in parallel. This segmentation allows the encoding process to work on multiple segments simultaneously, significantly reducing the overall encoding delay while still providing support for maximum information bit quantity when needed.
Solution Approach 2:
Instead of always using the full large interleving sequence even for small information bit quantities, the system applies partial action by using only the necessary portion of the interleaving sequence matched to the actual information bit quantity. This avoids the processing overhead of handling unnecessarily large sequences, thereby reducing encoding delay for typical operating conditions.
3Ease of manufacture
If conventional CRC encoding is used without distributed CRC, then the encoding process is simple, but early termination capability is lost
Solution Approach 1:
The CRC check process is segmented and distributed across multiple stages rather than being performed as a single conventional check at the end. By distributing CRC bits and performing checks at intermediate stages, the system enables early termination capability where decoding can stop sooner when errors are detected, improving decoding efficiency without making the overall process overly complex.
4Reliability
If dozens of decoding attempts are made in blind detection, then the probability of successful decoding increases, but decoding delay and energy consumption increase
Solution Approach 1:
Distributed CRC checks are performed preliminarily at intermediate stages during the decoding process rather than waiting until the end. This preliminary checking allows the system to detect decoding failures early and terminate the decoding attempt before completing all processing steps, thereby reducing the average decoding delay and energy consumption while maintaining the ability to perform multiple decoding attempts when necessary.
Data Source
AI summary
This application provides a channel encoding method and apparatus in wireless communications. The method includes: performing CRC encoding on A to-be-encoded information bits, to obtain a first bit sequence, where the first bit sequence includes L CRC bits and A information bits; performing a interleaving operation on the first bit sequence, to obtain a second bit sequence, where a first interleaving sequence used for the interleaving operation is obtained based on a system-supported maximum-length interleaving sequence with the length of Kmax+L, and Kmax is a maximum information bit quantity corresponding to the maximum-length interleaving sequence ad a preset rule, and a length of the first interleaving sequence is equal to A+L. Therefore, during distributed CRC encoding, when an information bit quantity is less than the maximum information bit quantity, an interleaving sequence required for completing an interleaving process is obtained based on the system-supported maximum-length interleaving sequence.