What Will the Future of UAV Cellular Communications Be? A Flight From 5G to 6G

TLDR

The article surveys the current state of UAV cellular communications, highlighting recent 3GPP updates and 5G NR features designed for aerial devices. It aims to chart the evolution from 5G to 6G for UAVs, presenting case studies and pinpointing the most promising 6G enablers to enhance performance and reliability. The authors dissect 5G capabilities, outline next‑generation use cases for the 2030s, and evaluate disruptive paradigms—non‑terrestrial networks, cell‑free architectures, AI, reconfigurable intelligent surfaces, and THz links—assessing their benefits and technical challenges. Their findings show that sub‑6 GHz massive MIMO mitigates cell‑selection and interference, mmWave coverage is encouraging in urban and rural areas, and direct device‑to‑device links exhibit unique characteristics, while also summarizing key takeaways and open research problems.

Abstract

What will the future of UAV cellular communications be? In this tutorial article, we address such a compelling yet difficult question by embarking on a journey from 5G to 6G and expounding a large number of case studies supported by original results. We start by overviewing the status quo on UAV communications from an industrial standpoint, providing fresh updates from the 3GPP and detailing new 5G NR features in support of aerial devices. We then dissect the potential and the limitations of such features. In particular, we demonstrate how sub-6 GHz massive MIMO can successfully tackle cell selection and interference challenges, we showcase encouraging mmWave coverage evaluations in both urban and suburban/rural settings, and we examine the peculiarities of direct device-todevice communications in the sky. Moving on, we sneak a peek at next-generation UAV communications, listing some of the use cases envisioned for the 2030s. We identify the most promising 6G enablers for UAV communication, those expected to take the performance and reliability to the next level. For each of these disruptive new paradigms (non-terrestrial networks, cellfree architectures, artificial intelligence, reconfigurable intelligent surfaces, and THz communications), we gauge the prospective benefits for UAVs and discuss the main technological hurdles that stand in the way. All along, we distil our numerous findings into essential takeaways, and we identify key open problems worthy of further study.