MTC Device Power Saving Mode Entry via Back-Off Timer

Solution Overview

Problem

Machine-type communication (MTC) devices face inefficiencies in power saving mode (PSM) due to network abnormalities, leading to rejected requests and inefficient energy consumption when they cannot enter PSM despite attempting to do so.

Innovation Solution

The method involves allowing MTC devices to enter PSM without retransmitting request messages upon receiving reject messages, thereby preventing radio resource waste and battery consumption, by implementing a retry counter and back-off timer mechanism.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If MTC devices retransmit request messages upon receiving reject messages to enter PSM, then the reliability of PSM entry is improved, but radio resource waste and battery consumption increase

Engineering Contradiction:

ImprovePSM entry reliabilityVSAvoidbattery consumption

Core Design Contradiction:

ReliabilityVSLoss of energy

Solution Approach 1:

The network pre-configures the MTC device with a back-off timer value before the device attempts to enter PSM. When the device receives a reject message, it uses this pre-configured timer to determine whether to retry or enter PSM, eliminating the need for repeated retransmission attempts and reducing energy consumption while maintaining reliable PSM entry

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The network provides feedback to the MTC device through the back-off timer configuration, enabling the device to make intelligent decisions about PSM entry attempts. This feedback mechanism allows the device to adjust its behavior based on network conditions, avoiding unnecessary retransmissions and optimizing battery usage

Inventive Principle:

Principle #23Feedback

2Reliability

If MTC devices retransmit request messages upon receiving reject messages to enter PSM, then the reliability of PSM entry is improved, but radio resource waste increases

Engineering Contradiction:

ImprovePSM entry reliabilityVSAvoidradio resource waste

Core Design Contradiction:

ReliabilityVSLoss of substance

Solution Approach 1:

The network pre-configures the MTC device with a back-off timer value before the device attempts to enter PSM. When the device receives a reject message, it uses this pre-configured timer to determine whether to retry or enter PSM, eliminating the need for repeated retransmission attempts and reducing radio resource waste while maintaining reliable PSM entry

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The network provides feedback to the MTC device through the back-off timer configuration, enabling the device to make intelligent decisions about PSM entry attempts. This feedback mechanism allows the device to adjust its behavior based on network conditions, avoiding unnecessary retransmissions and optimizing radio resource utilization

Inventive Principle:

Principle #23Feedback

3Loss of energy

If MTC devices enter PSM immediately upon network abnormality without retransmission, then battery consumption is reduced, but PSM entry reliability may deteriorate

Engineering Contradiction:

Improvebattery consumptionVSAvoidPSM entry reliability

Core Design Contradiction:

Loss of energyVSReliability

Solution Approach 1:

The network pre-configures the MTC device with a back-off timer value before the device attempts to enter PSM. When the device receives a reject message, it uses this pre-configured timer to determine whether to retry or enter PSM, eliminating the need for repeated retransmission attempts and reducing energy consumption while maintaining reliable PSM entry

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The back-off timer parameter is introduced to control the device's behavior. By adjusting this parameter, the system balances between immediate PSM entry (low energy consumption) and retry attempts (high reliability), allowing flexible optimization based on network conditions and device requirements

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentEP3096566B1Method for supporting power saving mode and wireless device thereof

Publication Date: 2019.03.13 LG ELECTRONICS INC

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AI summary

One embodiment of the present specification provides a method for supporting a power saving mode in a wireless device. The method can comprise the steps of: transmitting a request message including a first active time value to a network entity, if a PSM is necessary; and receiving a rejection message for the request message from the network entity. Here, the rejection message includes the reason for rejection, and can include a second active time value determined by considering the first active time value. The method can comprise the steps of terminating the transmission procedure of the request message after receiving the reject message, and entering a PSM state on the basis of the second active time value.