Integrated terrestrial-satellite networks (lTSNs) are envisioned to provide seamless broadband services through evolving terrestrial B5G/6G cellular systems and emerging mega satellite constellations. The inherent dual mobility (i.e., satellites and ubiquitous mobile users) and highly overlapped satellite footprints in such ITSNs may result in massive and frequent handovers. This increases handover delays, signaling overheads, and decision making loads, especially under existing fixed, even limited, deployments of ground mobility management functions (MMFs). Thus, a lightweight handover scheme and a mobility management architecture with dynamic MMF configurations are of great significance to guarantee service continuity and management timeliness. Specifically, this article proposes mobility management architectures with an augmented reconfigurable management plane on a higher orbit. The architectures can support flexible configurations of space-distributed MMFs for efficient mobility management together with the ground MMFs. Subsequently, to achieve rapid and unified decisions for massive handovers, we design a clustering and game-based handover decision framework including centralized and distributed decision making functions for different conditions. Based on handover procedures, simulation results validate the high performance of the proposed schemes regarding handover delays, signaling overheads, and convergence property. Notably, many academic issues are worthy of further studies under this architecture, such as higher-layer constellation design and inter-layer management structure optimization.

中文翻译：

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地面卫星综合网络的灵活分布式移动管理：挑战、架构和方法


综合地面卫星网络 (lTSN) 预计将通过不断发展的地面 B5G/6G 蜂窝系统和新兴的巨型卫星星座提供无缝宽带服务。这种ITSN中固有的双重移动性（即卫星和无处不在的移动用户）和高度重叠的卫星足迹可能会导致大规模和频繁的切换。这增加了切换延迟、信令开销和决策负载，特别是在地面移动管理功能（MMF）现有固定甚至有限部署的情况下。因此，轻量级切换方案和动态MMF配置的移动性管理架构对于保证业务连续性和管理及时性具有重要意义。具体来说，本文提出了在更高轨道上具有增强型可重构管理平面的移动管理架构。该架构可以支持空间分布式MMF的灵活配置，与地面MMF一起实现高效的移动管理。随后，为了实现大规模切换的快速统一决策，我们设计了一个基于集群和博弈的切换决策框架，包括针对不同情况的集中式和分布式决策功能。基于切换过程，仿真结果验证了所提出的方案在切换延迟、信令开销和收敛特性方面的高性能。值得注意的是，该架构下的许多学术问题值得进一步研究，例如高层星座设计和层间管理结构优化。