AI 中文总结
针对LEO卫星网络非均匀业务需求与星上功率约束问题，提出联合考虑业务需求与全网功耗的协作传输框架，开发两阶段算法优化传输架构与资源分配，性能优于基准方案。
AI 中文摘要
低轨（LEO）卫星网络被视为实现泛在连接、缩小数字鸿沟的有前景方案。LEO卫星星座的广覆盖特性使服务区域呈现空间非均匀的业务需求，同时星上功率约束严苛，高功耗传输架构吸引力低，亟需有效利用稀缺卫星网络资源的高能效传输策略。为此，本文提出一种协作传输框架，联合考虑非均匀业务需求与全网功耗。每颗LEO卫星集成混合预编码（HPC）、射频（RF）链激活与硬件量化，以统计信道状态信息（sCSI）和业务需求组建以用户设备（UE）为中心的卫星集群。设计协作传输架构与资源分配的联合优化框架，以最大化需求感知能效（EE），由此得到混合整数非线性规划（MINLP），其全局最优解通常难以求解。据此，在分布式线性预编码结构下开发两阶段算法：改进的交叉熵（CE）方法搜索离散变量，分式规划用于发射功率分配。数值结果表明，所提框架在兼顾业务需求与能效的前提下，性能优于基准方案。
英文摘要
Low Earth orbit (LEO) satellite networks are envisioned as a promising solution for providing ubiquitous connectivity and narrowing the digital divide. The extensive footprint of LEO satellite constellations enables broad coverage, resulting in spatially non-uniform traffic demand across the serviced areas. Meanwhile, stringent on-board power constraints make power-intensive transmission architectures less attractive and motivate energy-efficient transmission strategies that effectively exploit scarce satellite network resources. To this end, this paper proposes a cooperative transmission framework that jointly accounts for non-uniform traffic demand and network-wide power consumption. Each LEO satellite integrates hybrid precoding (HPC), radio frequency (RF) chain activation, and hardware quantization, while user-equipment (UE)-centric satellite clusters are organized using statistical channel state information (sCSI) and traffic demands. A framework for joint optimization of cooperative transmission architecture and resource allocation is designed to maximize demand-aware energy efficiency (EE), resulting in a mixed-integer nonlinear program (MINLP) for which finding a globally optimal solution is generally intractable. Accordingly, a two-stage algorithm is developed under a distributed linear precoding structure, in which a modified cross-entropy (CE) method searches over discrete variables, while fractional programming is employed for transmit power allocation. Numerical results indicate that the proposed framework outperforms benchmark schemes while accounting for traffic demands and EE.
Comments17 pages, 12 figures, accepted to IEEE Transactions on Wireless Communications
