DCI-Based TCI State Update for CORESET in NR Systems

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current methods for updating the Transmission Configuration Indicator (TCI) state of a Control Resource Set (CORESET) in New Radio (NR) systems face delays due to reliance on MAC-CE signaling, which is slower compared to Radio Resource Control (RRC) signaling, and lack clear configuration/signaling details for the RRC+MAC CE+DCI framework.

Innovation Solution

A framework is proposed that uses Downlink Control Information (DCI) to indicate the TCI state update, allowing for quicker updates by eliminating the need for MAC-CE based TCI state updates and providing configuration/signaling details for the three-stage RRC+MAC CE+DCI indication of TCI states, ensuring accurate CORESET identification for TCI state updates.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If MAC-CE signaling is used to update TCI state of CORESET, then the update can be performed, but the update process introduces delays and reduces efficiency

Engineering Contradiction:
ImproveTCI state update efficiencyVSAvoidTCI state update delay
Core Design Contradiction:
ProductivityVSLoss of time

Solution Approach 1:

The patent replaces the MAC-CE signaling mechanism with DCI-based signaling to update TCI states. Specifically, it uses a new DCI format (1_1 or 1_2) with a TCI indicator field that directly indicates the TCI state to be applied to the active BWP, eliminating the need for separate MAC-CE activation procedures and reducing update delays.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent pre-configures multiple TCI states through RRC signaling before they are needed for actual communication. These pre-configured TCI states are then可以快速 activated and applied through DCI signaling without requiring time-consuming configuration procedures, enabling rapid TCI state updates.

Inventive Principle:
Principle #10Preliminary action

2Reliability

If RRC signaling is used to configure TCI states, then comprehensive configuration is achieved, but the configuration process is slower compared to direct update needs

Engineering Contradiction:
ImproveTCI state configuration completenessVSAvoidConfiguration speed
Core Design Contradiction:
ReliabilityVSSpeed

Solution Approach 1:

The patent segments the TCI state configuration process into three distinct stages: (1) RRC signaling configures the initial set of TCI states, (2) MAC-CE signaling activates specific TCI states from the configured set, and (3) DCI signaling rapidly switches between activated TCI states. This segmentation allows each mechanism to optimize for its specific function while maintaining overall efficiency.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent introduces dynamic TCI state indication through DCI signaling that can rapidly switch between different TCI states based on current communication conditions. This dynamic mechanism allows the system to adapt TCI states in real-time without requiring slow RRC reconfiguration, bridging the gap between comprehensive configuration and rapid update needs.

Inventive Principle:
Principle #15Dynamics

3Adaptability or versatility

If multiple CORESETs are configured with different TCI states, then beam diversity is improved, but the complexity of identifying and updating the correct CORESET increases

Engineering Contradiction:
Improvebeam diversityVSAvoidCORESET identification complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent introduces a TCI state indicator field in the DCI as an intermediary mechanism that maps to specific TCI states. This indicator, combined with the active BWP context, serves as a mediator that uniquely identifies which CORESET(s) should apply the updated TCI state, simplifying the identification process while maintaining support for multiple CORESETs with different TCI states.

Inventive Principle:
Principle #24Intermediary (Mediator)

Data Source

PatentEP4193543B1Signaling for updating TCI state of a coreset with dci
Publication Date: 2024.05.15 TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)
  • EP4193543B1 patent drawingFigure 1~2
  • EP4193543B1 patent drawingFigure 3
  • EP4193543B1 patent drawingFigure 4

AI summary

Systems and methods of the present disclosure are directed to a method performed by a wireless communication device. The method includes receiving a configuration of a plurality of TCI states via RRC signaling. The method includes receiving a MAC CE that activates a subset of the plurality of TCI states. The method includes receiving a DCI that indicates one or more of the subset of the plurality of TCI states to be used and explicitly or implicitly indicates one or more particular CORESETs for which the one or more of the subset of the plurality of TCI states are to be used. The method includes using one or more spatial QCL downlink reference signals contained in the one or more of the subset of the plurality of TCI states to receive a PDCCH corresponding to the one or more particular CORESETs.