Deferred HARQ Feedback Multiplexing on PUSCH
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In wireless communication systems, especially in 5G and LTE networks, semi-persistent scheduling (SPS) hybrid automatic repeat request (HARQ) feedback often collides with downlink symbols due to slot format changes, leading to delays and reduced reliability in transmitting HARQ feedback on physical uplink shared channels (PUSCH).
Innovation Solution
The proposed solution involves deferring HARQ feedback and multiplexing it with PUSCH communications, allowing the UE to transmit the deferred HARQ feedback in the same slot as the collision, reducing the need for additional PUCCH resources and minimizing collisions with other UEs' transmissions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If HARQ feedback is transmitted on PUCCH resources, then feedback reliability is maintained, but resource collisions with downlink symbols occur due to slot format changes
Solution Approach 1:
The patent implements dynamic resource allocation by allowing HARQ feedback to be flexibly transmitted on either PUCCH or PUSCH resources depending on slot format conditions. When PUCCH resources collide with downlink symbols, the system dynamically switches to PUSCH resources, enabling adaptive response to changing channel conditions and slot configurations.
Solution Approach 2:
The patent changes the transmission parameter from fixed PUCCH resource allocation to variable resource allocation between PUCCH and PUSCH. The base station configures multiple PUSCH resources with different timing offsets, allowing the UE to select appropriate resources based on actual transmission conditions, thereby avoiding collisions while maintaining timely feedback.
2Reliability
If additional PUCCH resources are allocated to avoid collisions, then feedback reliability improves, but device complexity and resource overhead increase
Solution Approach 1:
The patent makes PUSCH resources serve dual functions: carrying uplink data and carrying deferred HARQ feedback. This multi-functionality eliminates the need for dedicated PUCCH resources in collision scenarios, reducing resource overhead and simplifying the overall resource allocation structure while maintaining feedback reliability.
Solution Approach 2:
The patent introduces PUSCH as an intermediary resource that mediates between the conflict of downlink symbol allocation and HARQ feedback transmission. By using PUSCH as a backup transmission path, the system resolves the resource collision without requiring complex PUCCH resource management.
3Adaptability or versatility
If HARQ feedback is deferred to PUSCH, then resource allocation flexibility improves, but transmission timing may be delayed
Solution Approach 1:
The base station pre-configures multiple PUSCH resources with different timing offsets before UE needs to transmit feedback. This preliminary preparation allows UE to immediately select the most appropriate resource when PUCCH collision occurs, minimizing decision latency and maintaining fast feedback transmission without complex real-time resource allocation.
Data Source
AI summary
Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive, from a base station, an indication to multiplex a deferred hybrid automatic repeat request (HARQ) feedback for a semi-persistent scheduling (SPS) downlink communication with a physical uplink shared channel (PUSCH) communication. The UE may transmit, to the base station, the deferred HARQ feedback for the SPS downlink communication multiplexed with the PUSCH communication. Numerous other aspects are described.