Satellite Terminal Tracking Area Update via Broadcast TAC Alternation
Solution Overview
Problem
The existing satellite communications systems face high signaling overheads when updating tracking areas (TAs), which is a significant technical challenge that needs to be addressed to improve efficiency and reduce unnecessary resource allocation.
Innovation Solution
A method where terminal devices receive broadcast messages from satellite devices that alternately carry tracking area codes (TACs) for multiple TAs, allowing the device to delay TA updates until it determines that it no longer belongs to any of the listed TAs, thereby reducing unnecessary signaling and resource allocation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the terminal device immediately initiates a TA update procedure upon detecting a TAC change in the broadcast message, then the tracking area information is updated timely, but unnecessary signaling overheads are generated during beam transitions
Solution Approach 1:
The terminal device performs preliminary detection of TAC changes and records them in a waiting list before actually initiating the TA update procedure. This preliminary action allows the device to distinguish between temporary TAC changes during beam transitions and permanent TA changes, thereby avoiding unnecessary signaling overhead while ensuring timely updates when truly needed.
2Reliability
If the terminal device continuously monitors broadcast messages to detect TAC changes, then the tracking area update is detected promptly, but the device complexity and processing overhead increase
Solution Approach 1:
The patent extracts the TAC detection and judgment logic from the continuous monitoring process by using a waiting list mechanism. The terminal device only needs to detect TAC changes and record them temporarily, deferring the complex update procedure until necessary. This separation reduces the real-time processing complexity while maintaining detection accuracy.
3Adaptability or versatility
If multiple TACs are allocated to a satellite beam covering multiple TAs, then the coverage flexibility is improved, but the complexity of TA list management increases
Solution Approach 1:
The patent introduces a waiting list as an intermediary data structure between the broadcast message reception and the TA list management. This waiting list temporarily stores detected TACs, allowing the terminal device to manage multiple TACs associated with a single beam without immediately complicating the TA list structure. The intermediary mechanism simplifies the management of multi-TAC scenarios.
Data Source
AI summary
A tracking area (TA) update method, a broadcast message transmission method, and a communications apparatus, where the tracking area update method includes: receiving a broadcast message periodically sent by a satellite device, where the broadcast message alternately carries tracking area codes (TACs) corresponding to one or more TAs of at least two TAs, and where coverage of a beam of the satellite device belongs to the at least two TAs; when detecting for the first time that a TA corresponding to a TAC in a broadcast message received in a current period does not belong to a first TA list, recording the TA in a second TA list; continuing detecting a subsequent broadcast message; and determining, based on a TAC in the subsequent broadcast message, whether to initiate a TA update procedure.