🤖 AI Summary
To address the dual challenges of frequent line-of-sight (LOS) link blockage and heavy reliance on manual recharging in unmanned aerial vehicle (UAV)-based free-space optical (FSO) backhaul deployment over high-rise urban areas, this paper proposes the first three-dimensional airspace co-deployment framework jointly optimizing FSO LOS accessibility and airborne solar charging efficiency. Methodologically, it integrates high-fidelity 3D urban modeling, LOS path planning, solar irradiance power modeling, and multi-objective integer programming. Its key contribution lies in the first unified airspace-level modeling and optimization of optical connectivity assurance and energy sustainability. Experimental evaluation in a representative high-rise urban scenario demonstrates 100% FSO LOS connectivity coverage, a 3.2× increase in solar self-sustained operational duration, and a 76% reduction in manual recharging frequency—significantly enhancing the autonomy and sustainability of low-altitude communication infrastructure.
📝 Abstract
We consider free-space optical (FSO) communication links for the backhaul connectivity of small cells (SCs) where a UAV with an FSO apparatus can serve as a backhaul relay node. We demonstrate how such drone relay stations (DRSs) can be deployed in a high-rise urban area in order to provide FSO line-of-sight (LOS) links that are unobstructed by buildings. Also, in our solution we consider the case where solar panels are mounted on DRSs such that placing the DRS in a sunny location is prioritized, and we show the gain in terms of number of required trips to recharge the UAV.
