In this paper, we consider downlink low Earth orbit (LEO) satellite communication systems where multiple LEO satellites are uniformly distributed over a sphere at a certain altitude according to a homogeneous binomial point process (BPP). Based on the characteristics of the BPP, we analyze the distance distributions and the distribution cases for the serving satellite. We analytically derive the exact outage probability, and the approximated expression is obtained using the Poisson limit theorem. With these derived expressions, the system throughput maximization problem is formulated under the satellite-visibility and outage constraints. To solve this problem, we reformulate it with bounded feasible sets and propose an iterative algorithm to obtain near-optimal solutions. Simulation results perfectly match the derived exact expressions for the outage probability and system throughput. The analytical results of the approximated expressions are fairly close to those of the exact ones. It is also shown that the proposed algorithm for the throughput maximization is very close to the optimal performance obtained by a two-dimensional exhaustive search.
翻译:在本文中,我们考虑低地球轨道卫星通信系统下行链路(LEO),其中多个低地球轨道卫星按照一个同质二分点进程(BPP)在某一高度上统一分布于某一区域。根据BPP的特性,我们分析了运行中的卫星的距离分布和分布情况。我们用Poisson限制理论来分析得出确切的流出概率和大致表达方式。有了这些衍生的表达方式,系统通过量最大化问题是在卫星可视性和流出限制下形成的。为了解决这个问题,我们用封闭的可行套件重新配置该系统,并提出一种迭代算法,以获得近乎最佳的解决方案。模拟结果完全符合外差概率和系统吞吐量的衍生确切表达方式。这些大致表达方式的分析结果与精确表达方式相当接近。还表明,拟议的通过量最大化的算法非常接近通过二维的彻底搜索取得的最佳性能。