Code Block Group HARQ Feedback for Lower Radio Latency
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Solution Overview
Problem
Existing wireless communication systems face inefficiencies in radio signal transceiving processes, particularly in handling large transport blocks and code blocks, leading to suboptimal resource use and increased latency in next-generation radio access technologies.
Innovation Solution
The proposed method involves configuring and transmitting Hybrid Automatic Repeat Request (HARQ) feedback in units of code blocks or code block groups (CBGs), rather than transport blocks, to optimize retransmission scheduling and reduce latency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If HARQ feedback is transmitted in units of transport blocks, then the feedback mechanism is simple to implement, but resource usage efficiency deteriorates and latency increases when handling large transport blocks
Solution Approach 1:
The transport block is segmented into multiple code blocks, and HARQ feedback is generated for each code block or code block group individually. This segmentation allows selective retransmission of only the failed code blocks rather than retransmitting the entire transport block, thereby improving resource usage efficiency while maintaining implementation feasibility through structured division
2Device complexity
If HARQ feedback is transmitted in units of transport blocks, then the feedback structure is simplified, but transmission latency increases due to unnecessary retransmission of successfully received data
Solution Approach 1:
By segmenting the transport block into code blocks and generating separate HARQ feedback for each, the system enables selective retransmission of only failed code blocks. This reduces the time required for successful data delivery by avoiding retransmission of already successfully received portions, thereby reducing transmission latency while maintaining manageable feedback structure complexity
Solution Approach 2:
The system dynamically adapts the HARQ feedback granularity based on transport block size and channel conditions. For smaller transport blocks, feedback is provided at the transport block level for simplicity; for larger transport blocks, feedback is provided at the code block or code block group level to optimize latency and resource efficiency, thus dynamically balancing complexity and performance
3Productivity
If code block group-based retransmission is implemented, then resource usage efficiency improves, but the complexity of the feedback mechanism increases
Solution Approach 1:
Code blocks are grouped into code block groups, and HARQ feedback is generated at the code block group level rather than individual code block level. This segmentation approach maintains resource usage efficiency by enabling selective retransmission while reducing feedback mechanism complexity compared to individual code block feedback, as fewer feedback bits are required
Data Source
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AI summary
The present invention relates to a wireless communication system, and more particularly, to a method and apparatus for receiving information on a number N of a code block group defined for one transport block from a base station through an upper layer signal, receiving a first transport block including a plurality of code blocks from the base station through a physical layer channel, and transmitting HARQ-ACK payload including HARQ-ACK information on the first transport block to the base station. Preferably, a code block-based CRC is attached to each of the code blocks, a transport block-based CRC is attached to the first transport block, and the HARQ-ACK payload includes a plurality of HARQ-ACK bits corresponding to M code block groups for the first transport block.