RISe of Flight: RIS-Empowered UAV Communications for Robust and Reliable Air-to-Ground Networks

TL;DR

This paper explores how UAVs equipped with reconfigurable intelligent surfaces (RIS) can enhance air-to-ground network connectivity, addressing challenges like UAV oscillations and environmental effects to improve robustness and reliability.

Contribution

It introduces RiFe and Fair-RiFe algorithms for optimal RIS configuration on UAVs, accounting for flight dynamics and atmospheric disturbances, a novel approach in UAV-assisted communications.

Findings

RiFe and Fair-RiFe outperform existing solutions in robustness.

Algorithms effectively compensate for UAV oscillations.

Enhanced connectivity reliability in various conditions.

Abstract

Next generation mobile networks need to expand towards uncharted territories in order to enable the digital transformation of society. In this context, aerial devices such as unmanned aerial vehicles (UAVs) are expected to address this gap in hard-to-reach locations. However, limited battery-life is an obstacle for the successful spread of such solutions. Reconfigurable intelligent surfaces (RISs) represent a promising solution addressing this challenge since on-board passive and lightweight controllable devices can efficiently reflect the signal propagation from the ground BSs towards specific target areas. In this paper, we focus on air-to-ground networks where UAVs equipped with RIS can fly over selected areas to provide connectivity. In particular, we study how to optimally compensate flight effects and propose RiFe as well as its practical implementation Fair-RiFe that automatically configure RIS parameters accounting for undesired UAV oscillations due to adverse atmospheric conditions. Our results show that both algorithms provide robustness and reliability while outperforming state-of-the-art solutions in the multiple conditions studied.