IRS-Aided Energy Efficient UAV Communication

TL;DR

This paper proposes energy minimization techniques for UAV communication systems using multiple IRSs, introducing a tractable model, deriving closed-form achievable rate expressions, and developing efficient algorithms that significantly reduce UAV energy consumption.

Contribution

It introduces a novel IRS-assisted model for UAV energy efficiency, derives closed-form rate expressions, and proposes low-complexity algorithms for energy minimization.

Findings

Proposed algorithms significantly reduce UAV energy consumption.

Exploiting multiple IRSs enhances energy efficiency.

Low complexity algorithms perform close to optimal solutions.

Abstract

Unmanned aerial vehicles (UAVs) have steadily gained attention to overcome the harsh propagation loss and blockage issue of millimeter-wave communication. However, UAV communication systems suffer from energy consumption, which limits the flying time of UAVs. In this paper, we propose several UAV energy consumption minimization techniques through the aid of multiple intelligent reflecting surfaces (IRSs). In specific, we introduce a tractable model to effectively capture the characteristics of multiple IRSs and multiple user equipments (UEs). Then, we derive a closed form expression for the UE achievable rate, resulting in tractable optimization problems. Accordingly, we effectively solve the optimization problems by adopting the successive convex approximation technique. To compensate for the high complexity of the optimization problems, we propose a low complexity algorithm that has marginal performance loss. In the numerical results, we show that the proposed algorithms can save UAV energy consumption significantly compared to the benchmark with no IRSs, justifying that exploiting the IRSs is indeed favorable to UAV energy consumption minimization.