Resolving SCell Activation Ambiguity via DCI Priority

Solution Overview

Problem

There is a need to address the ambiguity in controlling secondary cells (SCells) in LTE and NR systems, particularly when a user equipment receives simultaneous activation and deactivation MAC control elements (CE) and downlink control information (DCI), leading to signaling ambiguity issues.

Innovation Solution

A method and apparatus for controlling SCells, where a user equipment and network node process and transmit downlink control information (DCI) and medium access control (MAC) control elements (CE) to determine whether to apply or ignore these signals, ensuring clear control of SCell activation and deactivation, thereby resolving ambiguity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If both DCI and MAC CE are used to control SCell activation and deactivation, then control flexibility is improved, but signaling ambiguity occurs when simultaneous activation and deactivation signals are received

Engineering Contradiction:

Improvecontrol flexibilityVSAvoidsignaling clarity

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The patent inverts the traditional approach by making DCI the primary control mechanism and MAC CE the secondary mechanism. When DCI is present, it takes precedence over MAC CE for SCell activation/deactivation control. This inversion resolves the ambiguity by establishing a clear priority hierarchy where DCI overrides MAC CE when both are received simultaneously.

Inventive Principle:

Principle #13The other way round (Inversion)

Solution Approach 2:

The patent introduces a priority judgment mechanism as an intermediary between DCI and MAC CE control signals. This intermediary evaluates the presence and type of control signals, determines their priority based on predefined rules (DCI > MAC CE), and selects the appropriate control action, thereby eliminating signaling ambiguity.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Ease of operation

If MAC CE is used for SCell activation and deactivation control, then control capability is provided, but signaling ambiguity arises in NR systems when simultaneous activation and deactivation MAC CEs are received

Engineering Contradiction:

Improvecontrol capabilityVSAvoidsignaling clarity

Core Design Contradiction:

Ease of operationVSReliability

Solution Approach 1:

The patent introduces a priority judgment mechanism as an intermediary between DCI and MAC CE control signals. This intermediary evaluates the presence and type of control signals, determines their priority based on predefined rules (DCI > MAC CE), and selects the appropriate control action, thereby eliminating signaling ambiguity.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent inverts the traditional approach by making DCI the primary control mechanism and MAC CE the secondary mechanism. When DCI is present, it takes precedence over MAC CE for SCell activation/deactivation control. This inversion resolves the ambiguity by establishing a clear priority hierarchy where DCI overrides MAC CE when both are received simultaneously.

Inventive Principle:

Principle #13The other way round (Inversion)

3Measurement precision

If DCI is used for SCell control, then control precision is improved, but device complexity increases due to the need to process and prioritize multiple control signals

Engineering Contradiction:

Improvecontrol precisionVSAvoidsignal processing complexity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent changes the priority parameter of control signals based on their type. DCI is assigned higher priority than MAC CE, and this priority parameter is used to resolve conflicts when multiple signals are received simultaneously. This parameter-based priority system simplifies the processing logic compared to analyzing signal content and timing relationships.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent introduces a priority judgment mechanism as an intermediary between DCI and MAC CE control signals. This intermediary evaluates the presence and type of control signals, determines their priority based on predefined rules (DCI > MAC CE), and selects the appropriate control action, thereby eliminating signaling ambiguity.

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentUS11310867B2Method and apparatus of controlling secondary cell

Publication Date: 2022.04.19 GUANGDONG OPPO MOBILE TELECOMMUNICATIONS CORP LTD

AI summary

A method and an apparatus of controlling a secondary cell (SCell) are provided. The method of controlling the SCell for new radio carrier aggregation of a user equipment includes receiving at least one of downlink control information (DCI) and a medium access control (MAC) control element (CE) from a network node, wherein the at least one of the DCI and the MAC CE indicates control a SCell, the method includes determining whether to apply or ignore the at least one of the DCI and the MAC CE, and controlling the SCell according to the determination.