Besides promotion in the spectrum efficiency, orbital angular momentum (OAM) can bring additional benefits to physical layer security. In this study, the authors will highlight the benefit of covert transmissions to deal with the contradiction between transmission rate and security in the traditional direct sequence spread spectrum (DSSS) system. Based on OAM, a secure high-speed spread spectrum (SS) transmission system is proposed. Specifically, the system architecture and mathematical models are established. Afterwards, the detection method for the proposed OAM SS system is investigated. Meanwhile, the corresponding bit error rate (BER) and performance of anti-interception are analysed. The performance of data anti-interception is evaluated based on computational complexity, while the performance of signal anti-interception is studied by Neyman–Pearson criterion. Furthermore, Monte–Carlo simulations are also implemented to show the effectiveness of the proposed system. Compared with the traditional DSSS system, the higher security can be achieved by the proposed system. Besides, the transmission rates and BERs are the same for the traditional DSSS system and proposed system. Therefore, the proposed OAM SS transmission system successfully handles the contradiction of the transmission rate and security. In other words, the secure high-speed transmission can be achieved by the proposed OAM SS system.

中文翻译：

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具有轨道角动量的安全高速扩频传输系统

除了提高频谱效率外，轨道角动量（OAM）还可为物理层安全性带来更多好处。在这项研究中，作者将重点介绍隐蔽传输的好处，以解决传统直接序列扩频（DSSS）系统中传输速率与安全性之间的矛盾。基于OAM，提出了一种安全的高速扩频（SS）传输系统。具体而言，建立了系统架构和数学模型。然后，研究了所提出的OAM SS系统的检测方法。同时，分析了相应的误码率（BER）和抗拦截性能。基于计算复杂度来评估数据防拦截的性能，信号抗拦截的性能是通过Neyman–Pearson准则研究的。此外，还执行了蒙特卡洛模拟，以证明所提出系统的有效性。与传统的DSSS系统相比，该系统具有更高的安全性。此外，传统DSSS系统和建议系统的传输速率和BER相同。因此，提出的OAM SS传输系统成功地解决了传输速率和安全性之间的矛盾。换句话说，通过提出的OAM SS系统可以实现安全的高速传输。所提出的系统可以实现更高的安全性。此外，传统DSSS系统和建议系统的传输速率和BER相同。因此，提出的OAM SS传输系统成功地解决了传输速率和安全性之间的矛盾。换句话说，通过提出的OAM SS系统可以实现安全的高速传输。所提出的系统可以实现更高的安全性。此外，传统DSSS系统和建议系统的传输速率和BER相同。因此，提出的OAM SS传输系统成功地解决了传输速率和安全性之间的矛盾。换句话说，通过提出的OAM SS系统可以实现安全的高速传输。