Autonomous vehicles and Intelligent Transport Systems (ITS) have started to become a reality in recent years. However, shortcomings of these early intelligent vehicles demonstrate a need to increase an intelligent vehicle’s perceptual bubble beyond the vehicle’s onboard sensors. Vehicle-to-Everything (V2X) communications is a technology intended to enable intelligent vehicles to increase their perceptive range via communication with the outside world, i.e., other vehicles, road users, and infrastructure. One of the critical layers of V2X communications is that of the underlying wireless access. There remains an open debate on which technology (or technologies) will ultimately be adopted as the de facto wireless access technology for V2X communications. Presently, a myriad of unconnected threads of work are being undertaken to this end, resulting in an unclear picture of the current state of wireless access for V2X communications. In this tutorial review, we collate current research on wireless access for V2X communications to showcase recent developments and the challenges facing candidate technologies. To allow the reader to engage with the debate, we present an overview of the field of V2X communications, its history, and standardisation. Following this, we provide an overview of the key candidate wireless access technologies that may enable V2X communications. Through this work, we aim to provide a comprehensive first step into the discipline of wireless access for V2X communications.

中文翻译：

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V2X 通信的无线接入：研究、挑战和机遇


近年来，自动驾驶汽车和智能交通系统（ITS）已开始成为现实。然而，这些早期智能车辆的缺点表明，需要增加智能车辆的感知气泡，使其超出车辆的车载传感器。车对万物（V2X）通信是一种旨在使智能车辆通过与外界（即其他车辆、道路使用者和基础设施）通信来扩大其感知范围的技术。 V2X 通信的关键层之一是底层无线访问层。关于哪种技术（或多种技术）最终将被采用作为 V2X 通信事实上的无线接入技术，仍然存在公开争论。目前，大量未连接的工作正在为此进行，导致 V2X 通信无线接入的当前状态不清楚。在本教程回顾中，我们整理了当前有关 V2X 通信无线接入的研究，以展示最新的发展以及候选技术面临的挑战。为了让读者参与辩论，我们概述了 V2X 通信领域、其历史和标准化。接下来，我们概述了可实现 V2X 通信的关键候选无线接入技术。通过这项工作，我们的目标是为 V2X 通信无线接入学科迈出全面的第一步。