Joint Beamforming and Trajectory Design for Unmanned Aerial Vehicle Communications Based on Reconfigurable Intelligent Surface

Nantong Daxue xuebao. Ziran kexue ban

SUN Qiang¹  AI Bo²  GUO Yajing²  ZHANG Jiayi³ 

[1] China Mobile Group Shanxi Company Limited;School of Electronic Information Engineering, Beijing Jiaotong University;School of Information Science and Technology, Nantong Universit;

关键词: unmanned aerial wehicle;    reconfigurable intelligent surface;    jointly optimize;    passive beamforming;    trajectory optimization;   

DOI  :  10.12194/j.ntu.20210113001

来源: DOAJ

【 摘 要 】

As the communication network develops into the "air-sky-earth-sea" three-dimensional architecture, the application of unmanned aerial vehicle(UAV) in communication has attracted extensive attention. Compared with the traditional method, the UAV communication method with the direct path, as the dominant channel, has more stable and reliable communication performance. However, with the use of high-frequency signals, direct paths are also more susceptible to complex environments. As a new type of green communication technology, reconfigurable intelligent surface(RIS) can intelligently reflect signals to improve the propagation environment of signals improving system performance. Therefore, the RIS-assisted UAV communication system was studied, by jointly designing RIS passive beamforming and UAV trajectory to maximize the spectral efficiency of system. First, the optimal RIS phase shift that maximizes the signal-to-noise ratio under any UAV trajectory was obtained. Then, the flight track of UVA was optimized based on tabu search algorithm. Finally, the simulation results prove that the proposed joint optimization algorithm can not only find a better UAV position before the direct flight scheme and the heuristic scheme, but also improve the maximum spectral efficiency by 28% and 16%.