This paper investigates an average secrecy rate (ASR) maximization problem for an unmanned aerial vehicle (UAV) enabled wireless communication system, wherein a UAV is employed to deliver confidential information to a ground destination in the presence of a terrestrial passive eavesdropper. By employing an artificial noise (AN) injection based secure two-phase transmission protocol, we aim at jointly optimizing the UAV's trajectory, network transmission power, and AN power allocation over a given time horizon to enhance the ASR performance. Specifically, we divide the original non-convex problem into four subproblems, and propose a successive convex approximation based efficient iterative algorithm to solve it suboptimally with guaranteed convergence. Simulation results demonstrate significant security advantages of our designed scheme over other known benchmarks, particularly for stringent flight durations.

中文翻译：

---

安全人工噪声辅助无人机通信的联合轨迹和功率分配设计

本文研究了无人飞行器（UAV）使能的无线通信系统的平均保密率（ASR）最大化问题，其中在地面无源窃听者的存在下，UAV用于将机密信息传递到地面目的地。通过采用基于人工噪声（AN）的安全两相传输协议，我们旨在在给定的时间范围内共同优化无人机的航迹，网络传输功率和AN功率分配，以增强ASR性能。具体来说，我们将原始的非凸问题分为四个子问题，并提出了一种基于连续凸逼近的高效迭代算法，以保证收敛性地进行次优求解。