Evaluation of 3D Terrestrial and Aerial Spectrum Sharing with Massive MIMO Systems
Achiel Colpaert, Zhuangzhuang Cui, Sofie Pollin
TL;DR
This study addresses 3D spectrum sharing for aerial and terrestrial users using a 64-antenna massive MIMO base station. It combines real CSI measurements from a drone-mounted UE with SUS and zero-forcing scheduling to evaluate spectral efficiency and determine optimal aerial-terrestrial user mixes. The key contributions are the CSI measurement campaign, demonstration of 3D sharing with advanced combining, and a detailed analysis of how user scheduling affects SE under different layer allocations. The findings show that semi-orthogonal scheduling extends SE and that the optimal aerial-terrestrial mix depends on channel characteristics and link geometry, informing design choices for future non-terrestrial and 3D networks.
Abstract
Connecting aerial and terrestrial users with a single base station (BS) is increasingly challenging due to the rising number of aerial users like unmanned aerial vehicles (UAVs). Traditional BSs, designed with down-tilted beams, focus mainly on ground users, but massive MIMO (mMIMO) systems can significantly enhance coverage in low-altitude airspace. This paper analyzes how a mMIMO BS serves both aerial and terrestrial users in a 3D spectrum-sharing scheme. Using Semi-orthogonal User Selection (SUS) and random scheduling, we assess the spectral efficiency and performance limits of these systems. Results reveal that mMIMO effectively supports more terrestrial users, influenced by channel characteristics and user scheduling strategies, providing key insights for future 3D aerial-terrestrial networks.
