Elevation Angle-Dependent 3D Trajectory Design for Aerial RIS-aided Communication

TL;DR

This paper proposes an elevation angle-dependent 3D trajectory design for UAV-mounted RIS-assisted communication, optimizing the system to enhance data rates by jointly considering scheduling, phase shifts, and UAV path under probabilistic LoS conditions.

Contribution

It introduces a novel joint optimization framework for UAV trajectory, RIS phase shifts, and scheduling, considering elevation angle effects, which improves communication performance over existing methods.

Findings

Significant performance improvement over existing schemes.

Elevation angle and distance trade-off insights.

Efficient iterative algorithm for non-convex optimization.

Abstract

This paper investigates an aerial reconfigurable intelligent surface (RIS)-aided communication system under the probabilistic line-of-sight (LoS) channel, where an unmanned aerial vehicle (UAV) equipped with an RIS is deployed to assist two ground nodes in their information exchange. An optimization problem with the objective of maximizing the minimum average achievable rate is formulated to jointly design the communication scheduling, the RIS's phase shift, and the three-dimensional (3D) UAV trajectory. To solve such a non-convex problem, we propose an efficient iterative algorithm to obtain its suboptimal solution. Simulation results show that our proposed design significantly outperforms the existing schemes and provides new insights into the elevation angle and distance trade-off for the UAV-borne RIS communication system.