Aperiodic SRS Triggering Without TPC in Enhanced DCI

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Solution Overview

Problem

Existing wireless communication technologies, such as NR and LTE, lack efficient methods for triggering aperiodic sounding reference signals (SRS) without power control commands, limiting flexibility and applicability in various transmission scenarios.

Innovation Solution

Implementing enhanced DCI formats that enable flexible SRS triggering, including scenarios with cross-carrier or cross-component carrier SRS transmission, even when power control commands are absent, by utilizing DCI formats like DCI format 2_3 to facilitate aperiodic SRS transmission with determined transmit power control.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If existing DCI formats are used for triggering aperiodic SRS, then power control commands are included, but flexibility and applicability in various transmission scenarios are limited

Engineering Contradiction:

ImproveSRS triggering flexibilityVSAvoidDCI format complexity

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The DCI format is segmented into essential components only (SRS request field, frequency domain resource assignment, time domain resource assignment, and SRS resource indicator), separating power control functionality into a distinct TPC command field that can be independently configured. This segmentation allows the base DCI format to remain simple while providing optional power control extension when needed.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The enhanced DCI format is designed to serve multiple functions: it can trigger aperiodic SRS transmissions with power control commands when needed, or trigger SRS transmissions without power control commands when not needed. The format universally handles both scenarios through optional field inclusion, making it adaptable to various transmission scenarios including cross-carrier and cross-component carrier SRS transmission.

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Adaptability or versatility

If DCI formats include power control commands for SRS triggering, then transmit power control is maintained, but flexibility for scenarios without power control is reduced

Engineering Contradiction:

ImproveTransmission scenario applicabilityVSAvoidPower control command information

Core Design Contradiction:

Adaptability or versatilityVSLoss of information

Solution Approach 1:

The power control command information is extracted as an optional TPC command field that can be selectively included or excluded from the DCI format based on transmission scenario requirements. When power control is not needed, the TPC field is omitted, allowing the DCI to trigger SRS transmissions without power control information, thus gaining flexibility for various transmission scenarios.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The DCI format dynamically adapts its structure based on transmission requirements. The presence or absence of the TPC command field is determined dynamically according to whether power control is needed for the specific SRS transmission scenario, enabling the format to be flexible and applicable to both power-controlled and non-power-controlled transmissions.

Inventive Principle:

Principle #15Dynamics

3Productivity

If enhanced DCI formats are implemented for flexible SRS triggering, then SRS usage versatility is improved, but DCI format complexity increases

Engineering Contradiction:

ImproveSRS transmission efficiencyVSAvoidDCI format structure

Core Design Contradiction:

ProductivityVSDevice complexity

Solution Approach 1:

The DCI format applies local quality by making the TPC command field optional rather than universal. This allows the format to maintain simplicity for scenarios where power control is not needed, while providing enhanced functionality where it is required. The complexity is localized only to where it is actually needed in specific transmission scenarios.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The enhanced DCI format uses a lightweight, simple structure for the core SRS triggering functionality, adding only minimal optional fields (TPC command and SRI) when needed. This approach keeps the basic format simple and efficient, adding complexity only when and where it is required for specific transmission scenarios.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

Data Source

PatentUS12574859B2Sounding reference signal triggering techniques

Publication Date: 2026.03.10 QUALCOMM INC

AI summary

Certain aspects of the present disclosure provide techniques for wireless communications by a user equipment (UE). The method generally includes receiving a downlink control information (DCI) with at least one block configured to trigger aperiodic sounding reference signal (SRS) transmission from the UE on at least one SRS resource set, determining a transmit power control (TPC) command to apply to the A-SRS if the DCI lacks a transmit power control (TPC) command for the at least one SRS set, and transmitting the A-SRS in accordance with the DCI and the determined TPC command.