Delayed Satellite Handover for RAB Drop Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In satellite communication systems, terminal handovers often result in disconnections due to the target radio network controller-satellite (RNCS) being unable to accept radio access bearers (RABs) from the source RNCS, leading to dropped RABs and user frustration.
Innovation Solution
The satellite communication system strategically delays the handover procedure when the link quality is above a threshold, allowing the target RNCS to prioritize handover requests based on RAB quality data, thereby minimizing dropped connections by delaying handovers with good link quality and expediting those with degraded link quality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the handover procedure is executed immediately when the terminal moves to a new satellite beam, then the terminal connectivity is maintained, but the target RNCS may be unable to accept additional RABs resulting in dropped connections
Solution Approach 1:
The system performs preliminary assessment of link quality metrics (signal strength, signal-to-interference ratio) before executing handover. By evaluating these metrics in advance, the system determines whether to proceed with immediate handover or delay it, preventing dropped RABs when the target RNCS cannot accept additional bearers.
Solution Approach 2:
The handover timing is made dynamic based on real-time link quality conditions. The system adjusts the handover execution timing by delaying it when link quality metrics indicate potential connection failures, and proceeding with immediate handover when conditions are favorable, thus optimizing both connectivity maintenance and RAB acceptance.
2Reliability
If the handover procedure is delayed when link quality is good, then the target RNCS can prioritize handover requests and minimize dropped connections, but the handover time is extended
Solution Approach 1:
The system implements dynamic handover timing by continuously monitoring link quality metrics and adjusting the handover execution timing accordingly. When link quality is good, the system delays handover to allow target RNCS to prioritize requests; when link quality degrades, the system expedites handover to maintain connectivity, thus optimizing the trade-off between connection stability and time loss.
Solution Approach 2:
The system uses feedback from link quality measurements (signal strength, signal-to-interference ratio) to control handover timing decisions. This feedback mechanism allows the system to adaptively delay handover when conditions permit and proceed when necessary, balancing connection stability with minimal time loss.
3Device complexity
If the target RNCS accepts all handover requests without prioritization, then the handover processing is simplified, but the available bandwidth and throughput are insufficient resulting in dropped RABs
Solution Approach 1:
The system applies local quality assessment by evaluating link quality metrics specific to each handover request. The target RNCS uses these localized quality measurements to prioritize handover requests, accepting those with better link quality first. This allows the system to maintain simple processing while improving RAB acceptance rate through quality-based prioritization.
Data Source
AI summary
A first computer that includes a processor and memory storing instructions executable by the processor—the processor is programmed to: establish a satellite link between a satellite terminal and the first computer, the link comprising at least one radio access bearer (RAB); receive a rejection message from a second computer indicating that the second computer refuses to accept a terminal handover; and in response to receiving the rejection message, transmit to the second computer a pending handover request message comprising an indication of a link quality of the at least one RAB.