Cell Handover Call Hold for TAC Update Failures
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Solution Overview
Problem
Existing communication technologies fail to address the issue of call drops in mobile communication systems when a terminal device moves between cells with different tracking area codes, leading to interrupted calls due to unresponsive core network updates and inconsistent bearer configurations.
Innovation Solution
A communication method that maintains the calling state by detecting handover to a new cell, initiating a first communication cell update request, and holding the call if the response is not received within preset duration, thereby avoiding subsequent call drops by suspending local release and adjusting penalty levels based on call quality and network response.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the terminal device initiates a TAU request when moving between cells with different TAC LISTs, then the location information can be updated in the core network, but the call may be interrupted due to call drops when the core network does not respond or rejects the request
Solution Approach 1:
The terminal device performs preliminary actions by initiating the TAU request before the call is fully established, and prepares alternative actions (attaching procedure) in advance. The device monitors the TAU request status and has pre-configured fallback mechanisms to switch to attach procedure if TAU fails, preventing call drops before they occur.
Solution Approach 2:
The terminal device implements beforehand cushioning by maintaining buffer resources and alternative communication paths during the TAU process. When TAU request fails, the device has pre-allocated resources to immediately switch to attach procedure without interrupting the call, cushioning against the potential call drop.
2Reliability
If the terminal device performs an attach procedure to re-register on the core network after TAU rejection, then a new default bearer can be obtained, but the dedicated bearer linked to the previous default bearer cannot be recovered causing call interruption
Solution Approach 1:
The terminal device implements feedback mechanisms by monitoring the status of TAU requests and bearers. When TAU is rejected, the device receives feedback about the rejection reason and automatically adjusts its behavior by initiating attach procedure with appropriate parameters to preserve bearer configurations, using feedback from the network response to guide subsequent actions.
Solution Approach 2:
The terminal device applies parameter changes by modifying attach procedure parameters based on the TAU rejection scenario. The device changes bearer configuration parameters and attach parameters to ensure that when re-registering on the core network, the previous bearer configurations are preserved or quickly restored, preventing call interruptions.
3Adaptability or versatility
If the terminal device quickly moves between edges of multiple cells, then the device can maintain connectivity across different coverage areas, but frequent TAU requests increase the probability of call drops due to network response delays
Solution Approach 1:
The terminal device implements dynamics by making the TAU request behavior adaptive to current mobility conditions and network response status. The device dynamically adjusts whether to initiate TAU based on movement speed, signal quality, and previous TAU success rates, and dynamically switches between TAU and attach procedures based on real-time network responses, optimizing reliability during quick movement between cells.
Data Source
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AI summary
The present invention relates to the field of mobile communication technologies, and discloses a communication method, an apparatus, and a chip. The method includes: detecting that an electronic device is handed over from a first cell to a second cell; initiating a first communication cell update request; and in response to a call hold condition being satisfied, holding a calling state of the electronic device, where the call hold condition includes that the electronic device is currently in the calling state. This method can reduce a call drop probability of a terminal device.