In this letter, we study the simultaneously transmitting and reflecting reconfigurable intelligent surface (STAR-RIS) assisted unmanned aerial vehicle (UAV) communications. Our goal is to maximize the sum rate of all users by jointly optimizing the STAR-RIS's beamforming vectors, the UAV's trajectory and power allocation. We decompose the formulated non-convex problem into three subproblems and solve them alternately to obtain the solution. Simulations show that: 1) the STAR-RIS achieves a higher sum rate than traditional RIS; 2) to exploit the benefits of STAR-RIS, the UAV's trajectory is closer to STAR-RIS than that of RIS; 3) the energy splitting for reflection and transmission highly depends on the real-time trajectory of UAV.
@article{arxiv.2209.03777,
title = {Joint Optimization of STAR-RIS Assisted UAV Communication Systems},
author = {Qin Zhang and Yang Zhao and Hai Li and Shujuan Hou and Zhengyu Song},
journal= {arXiv preprint arXiv:2209.03777},
year = {2022}
}