Default Beam Selection for Multi-TCI 5G Channels

Solution Overview

Problem

Existing 5G wireless communication technologies face challenges in determining default beams for PDSCH, aperiodic CSI-RS, PUCCH, and SRS when multiple TCI states are configured, particularly in scenarios with scheduling offsets below a threshold and without spatial or pathloss reference signals.

Innovation Solution

A method for configuring default beams for PDSCH, PUCCH/SRS, and pathloss reference signals based on configuration information and monitoring a control resource set (CORESET) with the lowest identifier, using various options for selecting the CORESET when multiple TCI states are present.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If multiple TCI states are configured for a CORESET, then the system can support more flexible beam management and spatial filtering, but the complexity of determining default beams for PDSCH, PUCCH, and SRS increases

Engineering Contradiction:

Improvebeam management flexibilityVSAvoiddefault beam determination complexity

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent applies preliminary action by pre-configuring default beam rules before actual communication occurs. The UE is provided with configuration information that specifies default beam determination rules in advance, including identifying the CORESET with the lowest ID and selecting appropriate TCI states based on pre-established criteria. This eliminates the need for real-time complex analysis when determining default beams for PDSCH, PUCCH, and SRS.

Inventive Principle:

Principle #10Preliminary action

2Measurement precision

If the UE must determine default beams based on multiple TCI states, then beam accuracy can be improved, but the processing time and computational resources required increase

Engineering Contradiction:

Improvebeam accuracyVSAvoidbeam determination time

Core Design Contradiction:

Measurement precisionVSLoss of time

Solution Approach 1:

The patent applies preliminary action by pre-configuring default beam rules before actual communication occurs. The UE is provided with configuration information that specifies default beam determination rules in advance, including identifying the CORESET with the lowest ID and selecting appropriate TCI states based on pre-established criteria. This eliminates the need for real-time complex analysis when determining default beams for PDSCH, PUCCH, and SRS.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent applies parameter changes by establishing clear selection criteria that change the approach from evaluating multiple TCI states to selecting based on specific parameters such as CORESET ID and TCI state configuration. The UE determines the default beam by applying these predefined parameter-based rules rather than performing comprehensive analysis of all possible beam configurations.

Inventive Principle:

Principle #35Parameter changes

3Productivity

If default beam configuration is simplified to use the lowest CORESET ID, then the determination process becomes faster and less complex, but the ability to optimize beam selection based on multiple TCI states is reduced

Engineering Contradiction:

Improvebeam determination efficiencyVSAvoidbeam selection accuracy

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The patent applies parameter changes by establishing clear selection criteria that change the approach from evaluating multiple TCI states to selecting based on specific parameters such as CORESET ID and TCI state configuration. The UE determines the default beam by applying these predefined parameter-based rules rather than performing comprehensive analysis of all possible beam configurations.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent applies the intermediary principle by introducing configuration information as a mediator between the network and UE. This configuration information includes predefined rules and parameters that guide the UE in selecting the appropriate default beam. The intermediary configuration information allows the system to maintain simplicity while ensuring reliability through network-provided guidance on which TCI states to use.

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentUS12506582B2Default beams for PDSCH, CSI-RS, PUCCH and SRS

Publication Date: 2025.12.23 APPLE INC

AI summary

A method and apparatus configuring default beams are described.In some embodiments, the method of wireless communication at a User Equipment (UE) comprises: receiving, from a base station, configuration information for configuring a default beam for the physical downlink shared channel (PDSCH) to use on condition that an offset between reception of downlink control information (DCI) in the scheduling physical downlink control channel (PDCCH) and corresponding PDSCH is less than a threshold and at least one Transmission Configuration Indicator (TCI) states includes spatial receiving parameters for configuring a quasi-co-location; configuring, by the UE, a default beam configuration for the PDSCH based on the configuration information and a monitored control resource set (CORESET) with a lowest CORESET identifier (ID) from among a set of CORESETs in a latest slot in a same bandwidth part (BWP), wherein at least one CORSET of the set of CORESETs includes more than one TCI state; and receiving a transmission using the default beam.