Energy Minimization for Active RIS-Aided UAV-Enabled SWIPT Systems

TL;DR

This paper proposes an active RIS-aided UAV system for SWIPT, optimizing energy efficiency through trajectory and reflection vector design, demonstrating superior energy savings over passive RIS.

Contribution

It introduces an active RIS in UAV-enabled SWIPT systems and develops an optimization framework for energy minimization using SCA.

Findings

Active RIS achieves better energy savings than passive RIS.

Optimization of UAV trajectory and RIS reflection vectors improves system efficiency.

Simulation results validate the proposed approach's effectiveness.

Abstract

In this paper, we consider an active reconfigurable intelligent surface (RIS)-aided unmanned aerial vehicle(UAV)-enabled simultaneous wireless information and power transfer(SWIPT) system with multiple ground users. Compared with the conventional passive RIS, the active RIS deploying the internally integrated amplifiers can offset part of the multiplicative fading. In this system, we deal with an optimization problem of minimizing the total energy cost of the UAV. Specifically, we alternately optimize the trajectories, the hovering time, and the reflection vectors at the active RIS by using the successive convex approximation (SCA) method. Simulation results show that the active RIS performs better in energy saving than the conventional passive RIS.