标题： 低轨卫星覆盖之下的小世界：多层壳星座中的地面枢纽 显示英文标题

标题： The Small-World Beneath LEO Satellite Coverage: Ground Hubs in Multi-Shell Constellations

摘要： 近年来，大规模低地球轨道（LEO）卫星星座的出现为全球连接带来了前所未有的机遇。 然而，在多层架构中，路由效率和层间通信仍然是关键挑战。 本文研究了一个由10,956颗卫星和198个网关站（GSs）组成的典型六层巨型星座的结构特性和网络动态。 利用复杂网络分析工具，我们发现了几个关键结论：(1) 该星座表现出强大的小世界特性，即使在网络直径较大的情况下也能实现高效的路由；(2) GS中继在增强层间连通性方面起着关键作用，通过连接原本不相连的组件；(3) 馈线链路显著减少了平均路径长度，使远距离通信更加可行；(4) 中介分析揭示了GS之间的负载不平衡，表明需要采用流量感知的管理策略；(5) 该架构提供了出色的空域覆盖和弹性，在GS故障的情况下仍能保持连接性和低路由成本。 这些见解不仅解释了当前如SpaceX Starlink等巨型星座的设计原理，也为未来卫星网络基础设施的发展提供了有价值的指导。 显示英文摘要

摘要： In recent years, the emergence of large-scale Low-Earth-Orbit (LEO) satellite constellations has introduced unprecedented opportunities for global connectivity. However, routing efficiency and inter-shell communication remain key challenges in multi-shell architectures. This paper investigates the structural properties and network dynamics of a representative six-shell mega-constellation composed of 10,956 satellites and 198 gateway stations (GSs). Leveraging tools from complex network analysis, we identify several critical findings: (1) the constellation exhibits strong small-world characteristics, enabling efficient routing despite large network diameters; (2) GS relays play a pivotal role in enhancing inter-shell connectivity by bridging otherwise disconnected components; (3) feeder links significantly reduce average path length, making long-haul communication more feasible; (4) betweenness analysis reveals load imbalances among GSs, indicating the need for traffic-aware management strategies; (5) the architecture offers excellent spatial coverage and resilience, maintaining connectivity and low routing costs even under GS failures. These insights not only explain the design rationale behind current mega-constellations like SpaceX Starlink, but also provide valuable guidance for the evolution of future satellite network infrastructures.