Physical layer covert communication is a crucial secure communication technology that enables a transmitter to convey information covertly to a recipient without being detected by adversaries. Unlike typical cryptography and physical layer security systems that concentrate on protecting the sent signal content, covert communications seek to conceal the existence of legitimate transmission. Thus, with beyond fifth-generation (B5G) wireless communications, covert communications can operate in tandem or as a supplement to conventional security techniques. We provide an extensive overview of the basic theories and several strategies in physical layer covert communications in this article. In particular, we go into great detail about the basic theories of physical layer covert communications, such as channel models, codes, secret keys, and covertness metrics, as well as various covert schemes in progressively more complicated scenarios, such as covert communications in single-antenna and multiantenna three-node systems and covert communications in jammer- and relay-aided systems. In addition, we identify the challenges and future directions for research on covert communications in B5G wireless networks.

中文翻译：

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B5G 无线网络中的物理层隐蔽通信的研究、应用和挑战


物理层隐蔽通信是一种至关重要的安全通信技术，它使发送者能够秘密地将信息传递给接收者而不被对手检测到。与专注于保护发送信号内容的典型密码学和物理层安全系统不同，隐蔽通信试图隐藏合法传输的存在。因此，除了第五代 (B5G) 无线通信之外，隐蔽通信可以协同运行或作为传统安全技术的补充。在本文中，我们对物理层隐蔽通信的基本理论和几种策略进行了广泛的概述。特别是，我们详细介绍了物理层隐蔽通信的基本理论，例如信道模型、代码、密钥和隐蔽性度量，以及逐渐复杂的场景中的各种隐蔽方案，例如单个网络中的隐蔽通信。 -天线和多天线三节点系统以及干扰机和中继辅助系统中的隐蔽通信。此外，我们还确定了 B5G 无线网络中隐蔽通信研究的挑战和未来方向。