Adaptive C-DRX Configuration for Wireless Devices

Solution Overview

Problem

Current connected mode discontinuous reception (C-DRX) mechanisms in wireless communications have fixed short and long DRX cycle lengths, leading to inefficient power consumption as devices waste energy on dummy PDCCH monitoring, especially when no grants are received.

Innovation Solution

Implementing adaptive C-DRX configurations by allowing wireless devices to dynamically switch between sets of short and long DRX cycles based on the absence of scheduling grants, with network nodes configuring and reconfiguring these cycles using assistance information from devices to optimize power savings and communication efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of energy

If fixed short and long DRX cycle lengths are used, then the device can maintain simple C-DRX operation, but the device wastes energy on dummy PDCCH monitoring when no grants are received

Engineering Contradiction:

Improvepower consumptionVSAvoidC-DRX configuration complexity

Core Design Contradiction:

Loss of energyVSDevice complexity

Solution Approach 1:

The patent applies dynamics by enabling the wireless device to dynamically switch between different DRX cycle configurations (short and long cycles) based on whether scheduling grants are received. Instead of using fixed DRX cycles, the system adapts the cycle length in real-time, transitioning from short cycles during active communication to long cycles during idle periods, thereby reducing power consumption while maintaining communication responsiveness.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent implements parameter changes by modifying the DRX cycle duration parameter based on communication activity. The network node configures multiple DRX cycle parameters (short and long cycles), and the wireless device changes the active DRX cycle parameter depending on whether grants are received, optimizing power efficiency without requiring complex device architecture.

Inventive Principle:

Principle #35Parameter changes

2Reliability

If the device monitors PDCCH continuously with fixed DRX cycles, then the device can quickly respond to grants, but the device consumes excessive power during idle periods

Engineering Contradiction:

Improvegrant reception reliabilityVSAvoiddevice power consumption

Core Design Contradiction:

ReliabilityVSUse of energy by moving object

Solution Approach 1:

The patent applies dynamics by enabling the wireless device to dynamically switch between different DRX cycle configurations (short and long cycles) based on whether scheduling grants are received. Instead of using fixed DRX cycles, the system adapts the cycle length in real-time, transitioning from short cycles during active communication to long cycles during idle periods, thereby reducing power consumption while maintaining communication responsiveness.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent implements periodic action by using discontinuous reception cycles where the device periodically wakes up to monitor PDCCH and then returns to sleep mode. By configuring both short and long periodic cycles and switching between them based on activity, the system ensures reliable grant reception during active periods while minimizing power consumption during idle periods through extended sleep intervals.

Inventive Principle:

Principle #19Periodic action

3Adaptability or versatility

If the network reconfigures DRX cycles frequently, then the system can adapt to changing traffic patterns, but the signaling overhead and configuration complexity increase

Engineering Contradiction:

ImproveDRX adaptation to traffic patternsVSAvoidconfiguration management complexity

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent applies dynamics by enabling the wireless device to dynamically switch between different DRX cycle configurations (short and long cycles) based on whether scheduling grants are received. Instead of using fixed DRX cycles, the system adapts the cycle length in real-time, transitioning from short cycles during active communication to long cycles during idle periods, thereby reducing power consumption while maintaining communication responsiveness.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent implements feedback by using the reception (or non-reception) of scheduling grants as a feedback signal to trigger DRX cycle transitions. When grants are received, the device continues using short DRX cycles; when grants are not received, the device transitions to long DRX cycles. This feedback-driven approach enables automatic adaptation to traffic patterns without requiring complex network reconfiguration or extensive signaling overhead.

Inventive Principle:

Principle #23Feedback

Data Source

PatentUS12193102B2Methods and apparatuses for adaptive discontinuous reception configuration

Publication Date: 2025.01.07 TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)

AI summary

A method, network node and wireless device for adaptive connected discontinuous reception (C-DRX) configurations. According to one aspect, a method includes configuring a first set of short discontinuous reception, DRX, cycles and a second set of long DRX cycles, each DRX cycle having a duration for which the WD listens for an uplink grant from the network node. The method further includes transmitting to the WD at least a number of DRX cycles in the first set and a number of cycles in the second set.