Song Yi, Yang Weiwei, Xiang Zhongwu, Liu Yiliang, Cai Yueming
College of Communications Engineering, Army Engineering University of PLA, No. 88 Houbiaoying, Qinhuai District, Nanjing 210007, China.
School of Physics and Electronic Electrical Engineering, Huaiyin Normal University, Huai'an 223300, China.
Entropy (Basel). 2019 Apr 22;21(4):427. doi: 10.3390/e21040427.
Millimeter-wave (mmWave) communication is one of the key enabling technologies for fifth generation (5G) mobile networks. In this paper, we study the problem of secure communication in a mmWave wiretap network, where directional beamforming and link blockages are taken into account. For the secure transmission in the presence of spatially random eavesdroppers, an adaptive transmission scheme is adopted, for which sector secrecy guard zone and artificial noise (AN) are employed to enhance secrecy performance. When there exists no eavesdroppers within the sector secrecy guard zone, the transmitter only transmits information-bearing signal, and, conversely, AN along with information-bearing signal are transmitted. The closed-form expressions for secrecy outage probability (SOP), connection outage probability (COP) and secrecy throughput are derived under stochastic geometry. Then, we evaluate the effect of the sector secrecy guard zone and AN on the secrecy performance. Our results reveal that the application of the sector secrecy guard zone and AN can significantly improve the security of the system, and blockages also can be utilized to improve secrecy performance. An easy choice of transmit power and power allocation factor is provided for achieving higher secrecy throughput. Furthermore, increasing the density of eavesdroppers not always deteriorates the secrecy performance due to the use of the sector secrecy guard zone and AN.
毫米波（mmWave）通信是第五代（5G）移动网络的关键使能技术之一。在本文中，我们研究了毫米波窃听网络中的安全通信问题，其中考虑了定向波束成形和链路阻塞。对于存在空间随机窃听者的安全传输，采用了一种自适应传输方案，该方案采用扇区保密保护区域和人工噪声（AN）来增强保密性能。当扇区保密保护区域内不存在窃听者时，发射机仅发送承载信息的信号，反之，则发送人工噪声和承载信息的信号。在随机几何条件下，推导了保密中断概率（SOP）、连接中断概率（COP）和保密吞吐量的闭式表达式。然后，我们评估了扇区保密保护区域和人工噪声对保密性能的影响。我们的结果表明，扇区保密保护区域和人工噪声的应用可以显著提高系统的安全性，并且阻塞也可用于提高保密性能。为实现更高的保密吞吐量，提供了一种简单的发射功率和功率分配因子选择方法。此外，由于使用了扇区保密保护区域和人工噪声，增加窃听者的密度并不总是会降低保密性能。
