NR Sidelink DRX Coordination Without Central Synchronization

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing wireless communication systems face challenges in implementing discontinuous reception (DRX) on sidelinks due to the lack of a central point for synchronizing DRX cycles among user devices, leading to increased power consumption in devices with limited power supplies.

Innovation Solution

Implementing DRX on sidelinks by ranking multiple DRX configuration sources and selecting the highest ranked source, using adaptive DRX cycle lengths based on UE parameters and environment, aligning DRX cycles with access points or other UEs, and optimizing ON durations for power-saving purposes.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If DRX cycles are implemented on sidelinks without a central synchronization point, then device autonomy and flexibility are improved, but power consumption increases due to lack of coordination

Engineering Contradiction:

Improvedevice autonomyVSAvoidpower consumption

Core Design Contradiction:

Adaptability or versatilityVSUse of energy by moving object

Solution Approach 1:

The patent introduces a selected UE as an intermediary DRX configuration source that mediates between multiple DRX sources and other UEs. This intermediary role allows coordination of DRX cycles without requiring a central network point, thereby reducing power consumption while maintaining device autonomy. The selected UE ranks multiple DRX configuration sources and manages the DRX operation for the group.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent segments the DRX configuration management into hierarchical levels: network-provided configurations, UE-selected configurations from multiple sources, and UE-specific adaptations. This segmentation allows each UE to operate autonomously within its segment while contributing to overall system coordination, resolving the contradiction between autonomy and power efficiency.

Inventive Principle:

Principle #1Segmentation

2Adaptability or versatility

If multiple DRX configuration sources are available, then adaptability and coverage are improved, but complexity of selecting and managing configurations increases

Engineering Contradiction:

Improveconfiguration sourcesVSAvoidconfiguration management

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent implements feedback mechanisms where UEs report their DRX operation status and performance to the selected UE, which then adjusts the DRX configuration accordingly. This feedback loop simplifies management by automating the selection and adjustment process based on actual performance data, reducing the complexity of managing multiple configuration sources.

Inventive Principle:

Principle #23Feedback

Solution Approach 2:

The patent makes the DRX configuration dynamic by allowing UEs to switch between different DRX configuration sources based on current network conditions and performance requirements. The selected UE dynamically ranks and selects the most appropriate configuration source, transforming the static configuration management into a dynamic adaptive process that reduces complexity through automation.

Inventive Principle:

Principle #15Dynamics

3Reliability

If DRX ON durations are extended to ensure reliable communication, then communication reliability is improved, but power saving benefits are reduced

Engineering Contradiction:

Improvecommunication reliabilityVSAvoidpower saving

Core Design Contradiction:

ReliabilityVSUse of energy by moving object

Solution Approach 1:

The patent applies partial action by configuring UEs to monitor only specific sidelink channels and resources during ON durations rather than all possible transmissions. This selective monitoring approach maintains communication reliability for critical transmissions while reducing the overall ON duration and power consumption, achieving a balance between reliability and power saving.

Inventive Principle:

Principle #16Partial or excessive action

Solution Approach 2:

The patent changes the DRX parameters dynamically based on communication conditions. When communication reliability requirements are high, the ON duration is extended; when conditions are favorable, the ON duration is reduced. This parameter adaptation allows the system to optimize the trade-off between reliability and power saving in real-time based on actual network conditions.

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS12414192B2NR sidelink discontinuous reception

Publication Date: 2025.09.09 FRAUNHOFER GESELLSCHAFT ZUR FORDERUNG DER ANGEWANDTEN FORSCHUNG EV

AI summary

A user device, UE, for a wireless communication system is described. The wireless communication system has a plurality of user devices, UEs. The UE communicates with one or more further UEs using a sidelink, SL. To operate in a Discontinuous Reception, DRX, mode, the UE receives a DRX configuration from one of a plurality of DRX configuration sources. The plurality of DRX configuration sources are ranked such that each of the DRX configuration sources has a rank different from the remaining DRX configuration sources, and the UE is to select the DRX configuration from the DRX configuration source having the highest rank among the available DRX configuration sources.