PDCCH Multi-TCI Activation Across CORESETs for Beam Diversity

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Solution Overview

Problem

Existing cellular communication systems face challenges in efficiently activating multiple Transmission Configuration Indicator (TCI) states for the Physical Downlink Control Channel (PDCCH) across multiple Control Resource Sets (CORESETs) in diverse deployment scenarios, particularly in 5G networks, which affects reliability and efficiency of data transmission.

Innovation Solution

The method involves signaling from a network node to activate NTCI TCI states for one or more CORESETs, where NTCI > 1, enabling the reception of two or more TCI states for PDCCH in a single or multiple CORESETs, and utilizing a Medium Access Control (MAC) Control Element (CE) to configure and indicate these states, allowing for enhanced beam management and diversity in data transmission.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If only one TCI state is activated for PDCCH in existing systems, then device complexity is reduced and ease of operation is improved, but reliability and beam diversity are insufficient

Engineering Contradiction:

Improvedata transmission reliabilityVSAvoidTCI state management complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent segments the TCI state activation by introducing separate MAC CE mechanisms: one for activating TCI states for PDSCH and another for activating TCI states for PDCCH. This segmentation allows independent management of TCI states for different channels, enabling multiple TCI states to be activated for PDCCH without affecting PDSCH operations, thus improving reliability while managing complexity through structured separation.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent adds a new dimension to TCI state management by introducing a second activation mechanism specifically for PDCCH, rather than reusing the existing PDSCH activation mechanism. This dimensional separation allows the system to handle multiple TCI states for control channels independently, enabling beam diversity and enhanced reliability without overwhelming the existing single-dimension activation framework.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

2Adaptability or versatility

If multiple TCI states are activated for PDCCH, then beam diversity and transmission reliability are improved, but signaling overhead and MAC CE complexity increase

Engineering Contradiction:

Improvebeam management flexibilityVSAvoidsignaling overhead

Core Design Contradiction:

Adaptability or versatilityVSLoss of information

Solution Approach 1:

The patent extracts the PDCCH TCI state activation function from the PDSCH activation mechanism. By creating a dedicated MAC CE for PDCCH TCI state activation, the system can manage multiple TCI states for control channels without carrying unnecessary PDSCH-related signaling information. This extraction reduces signaling overhead while maintaining the ability to activate multiple TCI states for beam diversity.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent implements preliminary configuration of TCI state lists through RRC signaling, which pre-establishes the pool of available TCI states. The subsequent MAC CE activation only needs to indicate which pre-configured states to activate, rather than transmitting full TCI state information. This preliminary action significantly reduces signaling overhead while enabling flexible beam management with multiple TCI states.

Inventive Principle:

Principle #10Preliminary action

3Measurement precision

If separate MAC CE mechanisms are used for PDSCH and PDCCH TCI activation, then TCI state management precision is improved, but device complexity and processing overhead increase

Engineering Contradiction:

ImproveTCI state indication accuracyVSAvoidUE processing simplicity

Core Design Contradiction:

Measurement precisionVSEase of operation

Solution Approach 1:

The patent applies local quality by designing MAC CEs with field structures tailored to specific activation needs. The PDCCH TCI activation MAC CE contains fields optimized for control channel scenarios, while the PDSCH TCI activation MAC CE contains fields optimized for data channel scenarios. This localized optimization improves indication accuracy for each channel type while keeping each MAC CE structure relatively simple and purpose-specific.

Inventive Principle:

Principle #3Local quality

Data Source

PatentUS20250351151A1ACTIVATION OF TWO OR MORE TCI STATES FOR ONE OR MORE CORESETs

Publication Date: 2025.11.13 TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)

AI summary

Systems and methods are disclosed herein for activation of two or more Transmission Configuration Indication (TCI) states for a Physical Downlink Control Channel (PDCCH) in one or more Control Resource Sets (CORESETs) in a cellular communications system. In one embodiment, a method performed by a wireless communication device for activation of multiple TCI states for a PDCCH in one or more CORESETs in a cellular communications system comprises receiving, from a network node, signaling that activates NTCI TCI states for one or more CORESETs, wherein NTCI>1. In this manner, activation of two or more TCI states for PDCCH in one or more CORESETs is enabled.