Su Yishan, Han Guangyao, Fu Xiaomei, Xu Naishen, Jin Zhigang
School of Marine Science and Technology, Tianjin University, 300072 Tianjin, China.
School of Electrical Automation and Information Engineering, Tianjin University, 300072 Tianjin, China.
Sensors (Basel). 2017 Apr 6;17(4):781. doi: 10.3390/s17040781.
Physical layer security is an attractive security mechanism, which exploits the randomness characteristics of wireless transmission channel to achieve security. However, it is hampered by the limitation of the channel condition that the main channel must be better than the eavesdropper channel. To alleviate the limitation, cooperative communication is introduced. Few studies have investigated the physical layer security of the relay transmission model. In this paper, we performed some experiments to evaluate the physical layer security of a cooperative communication system, with a relay operating in decode-and-forward (DF) cooperative mode, selfish and malicious behavior in real non-ideal transmission environment. Security performance is evaluated in terms of the probability of non-zero secrecy capacity. Experiments showed some different results compared to theoretical simulation: (1) to achieve the maximum secrecy capacity, the optimal relay power according to the experiments result is larger than that of ideal theoretical results under both cooperative and selfish behavior relay; (2) the relay in malicious behavior who forwards noise to deteriorate the main channel may deteriorate the eavesdropper channel more seriously than the main channel; (3) the optimal relay positions under cooperative and selfish behavior relay cases are both located near the destination because of non-ideal transmission.
物理层安全是一种有吸引力的安全机制，它利用无线传输信道的随机性来实现安全。然而，它受到信道条件限制的阻碍，即主信道必须优于窃听信道。为了缓解这种限制，引入了协作通信。很少有研究探讨中继传输模型的物理层安全。在本文中，我们进行了一些实验，以评估协作通信系统的物理层安全，其中中继以解码转发（DF）协作模式运行，在真实的非理想传输环境中存在自私和恶意行为。安全性能根据非零保密容量的概率进行评估。实验显示出与理论模拟相比的一些不同结果：（1）为了实现最大保密容量，根据实验结果，在协作和自私行为中继情况下，最优中继功率均大于理想理论结果；（2）恶意行为中继向主信道转发噪声以使其恶化，可能会比主信道更严重地恶化窃听信道；（3）由于非理想传输，协作和自私行为中继情况下的最优中继位置均位于靠近目的地的位置。
