Site Diversity in Downlink Optical Satellite Networks Through Ground Station Selection

Recent advances have shown that satellite communication (SatCom) will be an important enabler for next generation terrestrial networks as it can provide numerous advantages, including global coverage, high speed connectivity, reliability, and instant deployment. An ideal alternative for radio frequency (RF) satellites is its free-space optical (FSO) counterpart. FSO or laser SatCom can mitigate the problems occurring in RF SatCom, while providing important advantages, including reduced mass, lower consumption, better throughput, and lower costs. Furthermore, laser SatCom is inherently resistant to jamming, interception, and interference. Owing to these benefits, this paper focuses on downlink laser SatCom, where the best ground station (GS) is selected among numerous candidates to provide reliable connectivity and maximum site diversity. To quantify the performance of the proposed scheme, we derive closed-form outage probability and ergodic capacity expressions for two different practical GS deployment scenarios. Furthermore, asymptotic analysis is conducted to obtain the overall site diversity gain, and aperture averaging is studied to illustrate the impact of aperture diameter on the overall performance. Finally, important design guidelines that can be useful in the design of practical laser SatComs are outlined

Network availability maximization for free-space optical satellite communications

This letter considers availability maximized ground station (GS) selection for free-space optical (FSO) satellite networks, which is a challenging problem in the area of optical satellite communications. As a main contribution of this letter, we propose to address this problem from a new perspective of mathematical optimization. In particular, we advocate a gradient projection based algorithm after performing smoothing and relaxation on the original problem. Simulation results and complexity analysis show that, when compared to the conventional GS selection methods, the proposed scheme achieves a better tradeoff between network availability and computational complexity.Fil: Gong, Shulei. Nanjing University; ChinaFil: Shen, Hong. National Mobile Communications Research Laboratory; ChinaFil: Zhao, Kanglian. Nanjing University; ChinaFil: Wang, Ruhai. Lamar University; Estados UnidosFil: Zhang, Xinggan. Nanjing University; ChinaFil: De Cola, Tomaso. German Aerospace Center; AlemaniaFil: Fraire, Juan Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentin