5G TCI State Determination Using Latest DCI Timing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In 5G wireless systems, there is ambiguity in determining which Transmission Configuration Indicator (TCI) state to apply after HARQ-ACK/NACK transmission, as multiple DCIs with different TCI states are conveyed in the same UL slot, leading to uncertainty in beam application time.
Innovation Solution
A method where the User Equipment (UE) detects multiple downlink control information (DCIs) and determines the latest DCI among them for which HARQ-ACK/NACK is transmitted, applying the corresponding TCI state after a specified number of symbols or slots following the acknowledgment, thereby resolving the ambiguity in beam application time.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If multiple DCIs with different TCI states are conveyed in the same UL slot, then beam management flexibility is improved, but ambiguity in determining which TCI state to apply arises
Solution Approach 1:
The patent applies preliminary action by establishing clear rules in advance for determining TCI state application timing. Specifically, it defines that when multiple DCIs are received in the same UL slot, the TCI state from the DCI with the latest timing shall be applied after a predetermined number of symbols or slots following the HARQ-ACK/NACK transmission. This pre-established rule eliminates ambiguity without requiring additional real-time decision-making or information exchange between UE and gNB.
2Measurement precision
If the latest DCI among multiple DCIs is selected for TCI state application, then beam application accuracy is improved, but processing complexity increases
Solution Approach 1:
The patent applies segmentation by dividing the TCI state determination process into distinct, manageable steps: (1) detect multiple DCIs in the UL slot, (2) identify the latest DCI based on timing, (3) determine the corresponding TCI state, and (4) apply it after the specified delay following HARQ-ACK/NACK transmission. This segmented approach allows the UE to systematically process multiple DCIs without overwhelming complexity, as each step builds on the previous one with clear transition rules.
3Stability of the object's composition
If TCI state is applied after HARQ-ACK/NACK transmission, then beam management timing is improved, but latency in beam switching increases
Solution Approach 1:
The patent applies parameter changes by optimizing the delay duration (specified number of symbols or slots) between HARQ-ACK/NACK transmission and TCI state application. This parameter can be configured based on UE capability, gNB requirements, and channel conditions to achieve the right balance between ensuring proper beam management timing and minimizing beam switching latency. The flexible parameter adjustment allows the system to adapt to different scenarios and requirements.
Data Source
AI summary
Systems, methods, apparatuses, and computer program products for determining transmission configuration indicator (TCI) state are provided. One method may include detecting, by a user equipment, one or more downlink control information (DCIs), and determining, by the user equipment, at least one of the one or more DCIs. Acknowledgement information for the determined at least one of the one or more DCIs is transmitted in a same symbol, in a same slot or in a same uplink channel. The method may also include determining, by the user equipment, a first TCI state indicated in a first DCI, where the first DCI is latest in time among the determined at least one of the one or more DCIs, and applying, by the user equipment, the first TCI state.