AI 中文总结
本研究针对自由空间量子网络的容量限制，提出用少量优化光纤骨干节点增强的方案，通过理论推导与数值模拟验证其可大幅提升网络容量、降低边消耗。
AI 中文摘要
自由空间量子通信是光纤量子网络的灵活补充，但其点对点容量受衍射、大气消光和湍流引起的光束漂移的根本限制。本研究将随机分布的固定或移动用户建模为Waxman随机图，研究大规模自由空间量子网络的端到端性能，推导单路径和多路径（泛洪）路由下的平均网络容量、边消耗及连通性相变；还研究以路由器为中心的星形网络，推导端到端容量随路由器覆盖半径变化的完整分布。随后考虑用少量位置优化的光纤骨干节点增强自由空间网络以提升性能，证明最优骨干配置需对应网络区域的容量最大化Voronoi图，可通过Lloyd算法的质心Voronoi图高效近似，骨干节点按Delaunay三角剖分连接。数值结果表明，少量骨干节点即可大幅提升移动和固定用户的端到端容量，降低边消耗。
英文摘要
Free-space quantum communication provides a flexible complement to fiber-based quantum networks, but its point-to-point capacity is fundamentally limited by diffraction, atmospheric extinction and beam wandering induced by turbulence. In this work, we study the end-to-end performance of large-scale free-space quantum networks connecting randomly distributed fixed or mobile users, modelled as Waxman random graphs. We derive the mean network capacity, edge consumption and connectivity phase transitions for both single-path and multi-path (flooding) routing. We also study router-centered star networks, deriving the full distribution of end-to-end capacities as a function of the router's coverage radius. We then consider how performance may be improved by reinforcing free-space networks with a small number of optimally placed fiber-based backbone nodes. We prove that any optimal backbone configuration must correspond to a capacity-maximizing Voronoi tessellation of the network region, and show that this can be efficiently approximated by a centroidal Voronoi tessellation via Lloyd's algorithm, with backbone nodes connected according to a Delaunay triangulation. Numerical results show that even a modest number of backbone nodes substantially improves end-to-end capacity and reduces edge consumption for both mobile and fixed users.
CommentsREVTeX. 21 pages. 8 Figures
