Subscriber Management via Tracking Area Updates

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current methods for managing multiple SIMs in user devices, such as Dual-SIM Dual Standby (DSDS), often result in state mismatches when switching between subscribers, leading to delayed communication and performance dips due to slow recovery from network assumptions of device disconnection.

Innovation Solution

Implementing a method where the user device transmits a status update, such as a Tracking Area Update or Routing Area Update, to inform the network of its resumed monitoring status, thereby expediting the correction of state mismatches and restoring service.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If the user device switches from receiving transmission according to a first subscriber to operating according to a second subscriber in DSDS mode, then the user device can handle priority communication on the second subscriber, but the network for the first subscriber assumes the device has moved outside coverage zone, leading to state mismatch and delayed communication recovery

Engineering Contradiction:
Improvemulti-subscriber handling capabilityVSAvoidservice restoration time
Core Design Contradiction:
Adaptability or versatilityVSLoss of time

Solution Approach 1:

The user device performs a tracking area update or routing area update message transmission to the network before or during the switch to the second subscriber. This preliminary action informs the network of the device's actual status and location, preventing the network from incorrectly assuming the device has moved outside coverage zone. By proactively updating the network state, the device avoids the state mismatch that would otherwise occur, enabling faster service restoration when switching back to the first subscriber.

Inventive Principle:
Principle #10Preliminary action

2Device complexity

If the user device uses a single transceiver for multiple SIMs in DSDS mode, then device complexity is reduced, but the device cannot simultaneously receive or transmit to multiple networks, causing communication delays

Engineering Contradiction:
Improvetransceiver configurationVSAvoidcommunication throughput
Core Design Contradiction:
Device complexityVSProductivity

Solution Approach 1:

The user device implements a feedback mechanism by transmitting tracking area update or routing area update messages to the network when switching between subscribers. This feedback informs the network of the device's operational status and current active subscriber, allowing the network to maintain accurate state information. The feedback loop prevents state mismatches and enables the network to efficiently manage resources, thereby improving communication throughput despite the limitation of using a single transceiver for multiple SIMs.

Inventive Principle:
Principle #23Feedback

Data Source

PatentEP3629672B1Multiple subscriber management in user device
Publication Date: 2023.05.31 APPLE INC
  • EP3629672B1 patent drawingFigure 1
  • EP3629672B1 patent drawingFigure 2
  • EP3629672B1 patent drawingFigure 3

AI summary

Disclosed is a method of subscriber management comprising controlling a transceiver to discontinue receiving a wireless transmission for a first subscriber and to transmit a wireless transmission for a second subscriber; returning operation of the transceiver to the first subscriber; and transmitting a status message to a network corresponding to the first subscriber.