发表机构
School of Integrated Circuits, Shanghai Jiao Tong University; Innovation Academy for Microsatellites of Chinese Academy of Science; Shanghai Institute of Satellite Engineering（上海交通大学集成电路学院; 中国科学院微小卫星创新研究院; 上海卫星工程研究所）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文针对配备可旋转天线的地面站与多低轨卫星的通信系统，构建双时间尺度吞吐量最大化问题，提出联合卫星选择与视轴轨迹优化的单调交替算法，仿真验证其性能优于基准方案，明确不同场景下卫星选择与RA成形的作用。
AI 中文摘要
本文研究一种卫星-地面通信系统，其中配备独立可旋转天线（RA）元件的地面站（GS）在共享时频资源上联合解码来自多个低地球轨道（LEO）卫星的独立数据流。具体而言，我们在外部同信道干扰下构建了一个双时间尺度吞吐量最大化问题，该问题涵盖服务集组成、RA支持的信道成形、时变卫星几何以及受机械约束的周期间重构。我们首先刻画了干扰白化信道强度与空间可分性对多卫星接收的联合影响，为卫星选择与RA控制的联合设计提供依据。在RA轨迹固定时，我们证明了周期级选择目标的单调次模性，并构建了基于当前值的紧模块化下界替代模型，从而得到一种高效的离散化极小化-最大化（MM）选择算法。在服务集固定时，我们基于黎曼梯度开发了 slew可行的RA更新方案，并将其组织为双色并行更新机制。两个模块被整合为具有目标收敛性保证的单调交替算法。仿真结果表明，与基准方案相比，所提方案可实现稳定增益，且揭示了信道强度与空间可分性之间的最优平衡。结果还进一步显示，在负载不足和执行器受限的场景中，卫星选择尤为重要，而在接近全空间负载时，RA成形的影响更为显著。
英文摘要
This paper considers a satellite-to-ground communication system in which a ground station (GS) equipped with independently rotatable antenna (RA) elements jointly decodes independent streams from multiple low-Earth-orbit (LEO) satellites over a shared time--frequency resource. Specifically, we formulate a two-timescale throughput maximization problem under exogenous cochannel interference, capturing serving-set composition, RA-enabled channel shaping, time-varying satellite geometry, and mechanically constrained inter-epoch reconfiguration. We first characterize the joint effects of interference-whitened channel strength and spatial separability on multi-satellite reception, motivating the joint design of satellite selection and RA control. With the RA trajectory fixed, we establish the monotone submodularity of the epoch-level selection objective and construct an incumbent-tight modular lower-bound surrogate, leading to an efficient discrete Minorization-Maximization (MM) selection algorithm. For fixed serving sets, we develop slew-feasible RA updates based on Riemannian gradients and organize them into a two-color parallel update scheme. The two blocks are integrated into a monotone alternating algorithm with guaranteed objective convergence. Simulations demonstrate consistent gains over benchmark schemes and reveal an optimal balance between channel strength and spatial separability. The results further show that satellite selection is particularly important in underloaded and actuator-limited regimes, whereas RA shaping becomes more influential near full spatial loading.
Comments13 pages, 9 figures. Submitted to an IEEE journal for possible publication
