Multi-TRP Downlink Reception Through TCI-Mapped Repetitions
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In future radio communication systems like NR and 5G, when a downlink shared channel is transmitted from multiple transmission and reception points (TRPs) for repetitive transmissions, the user terminal may fail to appropriately control the reception due to unavailability of accurate Transmission Configuration Indication (TCI) states.
Innovation Solution
The user terminal associates TCI states with repetition indices or redundancy versions of the downlink shared channel to ensure proper reception, using methods such as associating TCI states with repetition indices or RV indices, and employing DCI fields to indicate these states for each repetition or redundancy version.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If downlink shared channel is transmitted from multiple different TRPs for repetitive transmissions, then transmission reliability is improved, but reception control accuracy deteriorates due to unavailability of appropriate TCI state acknowledgement
Solution Approach 1:
The patent segments the downlink shared channel transmissions by associating different TCI states with different repetition indices or redundancy versions. This allows the terminal to distinguish and separately process signals from different TRPs, maintaining reception control accuracy while benefiting from multi-TRP transmission reliability.
Solution Approach 2:
The patent applies local quality by configuring specific TCI states for specific repetitions or redundancy versions. Each local segment (repetition/RV) receives appropriate TCI state configuration matching its transmitting TRP, enabling precise reception control for each segment while maintaining overall transmission reliability.
2Measurement precision
If TCI states are associated with repetition indices or redundancy versions, then reception control accuracy is improved, but device complexity increases due to additional configuration and indication mechanisms
Solution Approach 1:
The patent uses existing DCI fields and terminal processing mechanisms for multiple purposes - both for scheduling control and for TCI state indication. This multi-functionality approach improves reception control accuracy without adding separate dedicated configuration systems, thereby limiting complexity increase.
Solution Approach 2:
The terminal autonomously determines and applies the appropriate TCI state based on repetition indices or redundancy versions indicated in DCI. This self-service mechanism reduces network configuration overhead and simplifies the system by eliminating the need for extensive external configuration management.
Data Source
Figure 1A~1B
Figure 2A~2B
Figure 3A~3B
AI summary
To appropriately control, even when transmission of a downlink shared channel from different TRPs is performed repetitively, reception of the downlink shared channel. A user terminal according to an aspect of the present disclosure includes a receiving section that receives, on the basis of downlink control information, a downlink shared channel repetitively transmitted, and a control section that controls, in a case where a period from reception of the downlink control information until reception of the downlink shared channel is less than a certain threshold value, a TCI state for repetitions of the downlink shared channel on the basis of a specific set out of sets of configured transmission configuration indication states (TCI states).