부산대학교 도서관

Reconfigurable intelligent surface (RIS) has emerged as a key enabler to boost the performance in the upcoming wireless networks in a spectral/cost/energy-efficient manner. In contrast to terrestrial RISs coated on facades of buildings, aerial RISs benefit from flexible mobility and full-angle reflection by mounting the RISs on aerial platforms such as unmanned aerial vehicles (UAVs). However, the aerial platforms are sensitive to inevitable fluctuation, causing performance variations. In this letter, we develop a novel channel model for UAV-mounted RIS auxiliary millimeter wave (mmWave) mobile systems in the presence of UAV attitude fluctuation. Based on the proposed channel model, the closed-form expression for the signal-to-noise ratio (SNR) in terms of UAV attitude fluctuation is derived. The impact of fluctuation on the array receiving aperture and the maximum SNR is investigated. The filtering effect on maximum SNR brought by fluctuation is revealed, arising for the requirement of UAV attitude detection. Numerical results are provided to verify the accuracy of our derived results.