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-6GHz 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-to-device 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, cell-free 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.

中文翻译：

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无人机蜂窝通信的未来会是什么？从 5G 到 6G 的飞跃

无人机蜂窝通信的未来会是什么？在本教程文章中，我们通过开始从 5G 到 6G 的旅程并阐述大量由原始结果支持的案例研究来解决如此引人注目但又很困难的问题。我们首先从工业角度概述无人机通信的现状，提供来自 3GPP 的最新更新，并详细介绍支持航空设备的新 5G NR 功能。然后，我们剖析了这些功能的潜力和局限性。特别是，我们展示了 sub-6GHz 大规模 MIMO 如何成功应对小区选择和干扰挑战，展示了在城市和郊区/农村环境中令人鼓舞的毫米波覆盖评估，并研究了直接设备到设备通信的特殊性。天空。继续，我们偷偷看看下一代无人机通信，列出了 2030 年代设想的一些用例。我们确定了无人机通信最有前途的 6G 推动因素，这些推动因素有望将性能和可靠性提升到一个新的水平。对于这些颠覆性的新范式（非地面网络、无细胞架构、人工智能、可重构智能表面和太赫兹通信）中的每一个，我们评估了无人机的潜在优势，并讨论了阻碍的主要技术障碍。一直以来，我们将众多发现提炼成基本要点，并确定值得进一步研究的关键开放性问题。那些有望将性能和可靠性提升到一个新水平的产品。对于这些颠覆性的新范式（非地面网络、无细胞架构、人工智能、可重构智能表面和太赫兹通信）中的每一个，我们评估了无人机的潜在优势，并讨论了阻碍的主要技术障碍。一直以来，我们将众多发现提炼成基本要点，并确定值得进一步研究的关键开放性问题。那些有望将性能和可靠性提升到一个新水平的产品。对于这些颠覆性的新范式（非地面网络、无细胞架构、人工智能、可重构智能表面和太赫兹通信）中的每一个，我们评估了无人机的潜在优势，并讨论了阻碍的主要技术障碍。一直以来，我们将众多发现提炼成基本要点，并确定值得进一步研究的关键开放性问题。