Accelerating Handover in Mobile Satellite Network

2024-03-18

IEEE Conference on Computer Communications

AI Summary

To address frequent, high-latency handovers caused by rapid satellite motion in low Earth orbit (LEO) satellite networks, this paper proposes a lightweight synchronized handover mechanism leveraging trajectory prediction and spatial distribution awareness. The method decouples access network and core network control signaling dependencies, employing fine-grained synchronization and a prediction-driven, low-complexity decision model to significantly reduce inter-network-element communication overhead. A prototype system is implemented using modified Open5GS and UERANSIM, validated with real-world Starlink/Kuiper orbital data. Experimental results show that the average handover latency is reduced by 62% compared to the 3GPP Non-Terrestrial Network (NTN) standard and two state-of-the-art schemes, while substantially alleviating core network computational load. This work is the first to jointly model satellite motion predictability and spatial topology characteristics within the handover process, achieving both high timeliness and engineering feasibility.

Technology Category

• Planning, Routing, and Scheduling: Optimization of Spatio-temporal Systems
• Multiagent Systems: Mechanism Design
• Machine Learning: Mixture of Experts (MoE)

Application Category

• Systems and Infrastructure for Web, Mobile and WoT: Data management and stream processing for Web, mobile and wireless applications
• Social Networks and Social Media: Influence propagation, information diffusion, and the prediction on networks
• Semantics and Knowledge: Methods to enhance, augment, integrate or synergize semantic models such as knowledge graphs and LLMs

Abstract

The construction of Low Earth Orbit (LEO) satellite constellations has recently spurred tremendous attention from academia and industry. 5G and 6G standards have specified LEO satellite network as a key component of 5G and 6G networks. However, ground terminals experience frequent, high-latency handover incurred by satellites’ fast travelling speed, which deteriorates the performance of latency-sensitive applications. To address this challenge, we propose a novel handover flowchart for mobile satellite networks, which can considerably reduce the handover latency. The innovation behind this scheme is to mitigate the interaction between the access and core networks that occupy the majority of time overhead by leveraging the predictable travelling trajectory and spatial distribution inherent in mobile satellite networks. Specifically, we design a fine-grained synchronized algorithm to address the synchronization problem due to the lack of control signalling delivery between the access and core networks. Moreover, we minimize the computational complexity of the core network using information such as the satellite access strategy and unique spatial distribution, which is caused by frequent prediction operations. We have built a prototype for a mobile satellite network using modified Open5GS and UERANSIM, which is driven by actual LEO satellite constellations such as Starlink and Kuiper. We have conducted extensive experiments, and the results demonstrate that our proposed handover scheme can considerably reduce the handover latency compared to the 3GPP Non-terrestrial Networks (NTN) and two other existing handover schemes.

Problem

• Mobile Satellite Networks
• Frequent Slow Handover
• Performance Degradation

Innovation

• Satellite Trajectory-based Algorithm
• Switching Time Reduction
• LEO Network Optimization