Resorting to the exploitation of physical attributes, physical-layer authentication (PLA) is a promising technology to supplement and enhance current cryptography-based security mechanisms in wireless communications. in the fifth-generation (5G) communications, many disruptive technologies spring up, such as millimeter-wave communication (mmWave), massive multiple-input and multiple-output (MiMO) and non-orthogonal- multiple-access (NOMA). PLA schemes in 5G networks are facing challenges while exposed to opportunities at the same time. This article seeks to identify the critical technology gaps as well as the feasible enablers in terms of the unique characteristics of 5G networks. The investigation consists of four hierarchical parts. in the first section, existing PLA schemes are reviewed, and the corresponding challenges are discussed in the next section. in the third section, we investigate potential enablers based on the unique characteristics of 5G networks and provide three corresponding PLA case studies. Open problems and research directions on PLA for 5G and beyond are discussed in the last section, including waveform design, feature learning, mobile users, and terahertz communications.

中文翻译：

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5G通信的物理层身份验证：机遇与未来

依靠利用物理属性，物理层身份验证（PLA）是一种有前途的技术，可以补充和增强当前无线通信中基于密码学的安全机制。在第五代（5G）通信中，涌现出许多破坏性技术，例如毫米波通信（mmWave），大规模多输入多输出（MiMO）和非正交多址（NOMA）。5G网络中的PLA方案在面临机遇的同时面临挑战。本文旨在根据5G网络的独特特征确定关键的技术差距以及可行的促成因素。调查包括四个层次部分。在第一部分中，对现有的PLA计划进行了审查，下一节将讨论相应的挑战。在第三部分中，我们将基于5G网络的独特特征研究潜在的推动力，并提供三个相应的PLA案例研究。上一节讨论了针对5G及更高版本的PLA的开放问题和研究方向，包括波形设计，功能学习，移动用户和太赫兹通信。