Intelligent reflecting surface (IRS) is a promising technology for future communication systems because of its ability to intelligently configure the wireless environment. In this letter, an IRS is equipped on an unmanned aerial vehicle (UAV) as a passive relay system, in which the UAV serves as a flexible airborne platform. Our aim is to maximize the minimum average transmission rate by jointly optimizing the communication scheduling, phase shift of the IRS, and trajectory of the UAV. The coupling of the optimization variables and non-convexity make this problem hard to solve directly. Therefore, we divide the problem into three subproblems and apply the successive convex approximation (SCA) technique to solve this problem iteratively. Numerical results demonstrate that the minimum transmission rate can be greatly improved by adopting the proposed iterative algorithm, and also confirm the effectiveness of the algorithm.

中文翻译：

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IRS 辅助无人机网络的联合轨迹和通信设计


智能反射面（IRS）因其能够智能配置无线环境而成为未来通信系统一项有前途的技术。在这封信中，IRS被装备在无人机（UAV）上作为无源中继系统，其中无人机充当灵活的机载平台。我们的目标是通过联合优化通信调度、IRS 相移和无人机轨迹来最大化最小平均传输速率。优化变量的耦合和非凸性使得该问题难以直接求解。因此，我们将问题分为三个子问题，并应用逐次凸逼近（SCA）技术迭代解决该问题。数值结果表明，采用所提出的迭代算法可以极大地提高最小传输速率，也验证了算法的有效性。