In this work, we address the trajectory optimization of a fixed-wing unmanned aerial vehicle (UAV) using free space optical communication (FSOC). Here, we focus on maximizing the flight time of the UAV by considering practical constraints for wireless UAV communication, including limited propulsion energy and required data rates. We find optimized trajectories in various atmospheric environments (e.g., moderate-fog and heavy-fog conditions), while also considering the channel characteristics of FSOC. In addition to maximizing the flight time, we consider the energy efficiency maximization and operation-time minimization problem to find the suboptimal solutions required to meet those constraints. Furthermore, we introduce a low-complexity approach to the proposed framework. In order to address the optimization problem, we conduct a bisection method and sequential programming and introduce a new feasibility check algorithm. Although our design considers suboptimal solutions owing to the nonconvexity of the problems, our simulations indicate that the proposed scheme exhibits a gain of approximately 44.12% in terms of service time when compared to the conventional scheme.

中文翻译：

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无人机载自由空间光通信：飞行时间轨迹优化

在这项工作中，我们使用自由空间光通信 (FSOC) 解决了固定翼无人机 (UAV) 的轨迹优化问题。在这里，我们通过考虑无线无人机通信的实际约束，包括有限的推进能量和所需的数据速率，专注于最大化无人机的飞行时间。我们在各种大气环境（例如，中雾和重雾条件）中找到了优化的轨迹，同时还考虑了 FSOC 的通道特性。除了最大化飞行时间外，我们还考虑了能源效率最大化和运行时间最小化问题，以找到满足这些约束所需的次优解决方案。此外，我们为所提出的框架引入了一种低复杂度的方法。为了解决优化问题，我们进行了二分法和顺序编程，并引入了一种新的可行性检查算法。尽管由于问题的非凸性，我们的设计考虑了次优解决方案，但我们的模拟表明，与传统方案相比，所提出的方案在服务时间方面表现出大约 44.12% 的增益。