On the Downlink Performance of RSMA-based UAV Communications

TL;DR

This paper investigates the integration of rate-splitting multiple access with UAV-based base stations to enhance downlink spectral efficiency, proposing an optimization framework for UAV placement and RSMA parameters, validated through simulations.

Contribution

It introduces a novel joint optimization approach for UAV placement and RSMA parameters, improving downlink data rates in UAV-assisted networks.

Findings

Proposed an alternating optimization method for joint UAV and RSMA design.

Simulation results show significant performance gains over baseline methods.

Validated the effectiveness of RSMA in UAV communication scenarios.

Abstract

The use of unmanned aerial vehicles (UAVs) as base stations (BSs) is envisaged as a key enabler for the fifth generation (5G) and beyond-5G networks. Specifically, aerial base stations (UAV-BS) are expected to provide ubiquitous connectivity and high spectral efficiency. To this end, we present in this correspondence an in-depth look into the integration of rate-splitting multiple access (RSMA) with UAV-BSs and downlink transmissions. A non-convex problem of joint UAV placement, RSMA precoding, and rate splitting, aiming to maximize the weighted sum data rate of users is formulated. Due to its complexity, two sub-problems are investigated, namely the UAV placement and RSMA parameters optimization. The resulting solutions are then combined to propose a novel alternating optimization method. Simulation results illustrate the latter's efficiency compared to baseline approaches.