非理想条件下认知蜂窝网络物理层安全传输方案

认知无线电技术可以解决频谱实际利用率不高的问 题，作为关键技术之一被引入下一代蜂窝移动网络中。同时，由于无线信道的广播特性和 不确定性，非理想条件下的信息安全传输问题不可回避。由于认知无线网络中主、次网络间 存在相互干扰，文中借鉴干扰对准思想，高效地管理和利用主、次网络之间的相互干扰，通 过优化设计发送预编码矩阵，尽量避免干扰合法用户接收，同时尽可能地对窃听节点实施阻 塞干扰。Monte Carlo仿真验证了非理想条件下干扰对准设计预编码矩阵的优越性，同时也 证实了信道估计精度在提高蜂窝移动系统传输性能和安全性能方面的重要性。

Secure Transmission Protocol in Cognitive Cellular Networks Under Imperfect Conditions

Cognitive radio possesses the ability of solving the low spectrum utilization problem, which is introduced to the next-generation cellular networks. And the security under imperfect conditions should not be neglected due to the broad cast and uncertain characteristics of the wireless channels. In cognitive radio systems, interference between primary users and secondary users greatly affects the system performance. Based on interference alignment technique, the mutual interference between the primary network and the second network is efficiently managed and utilized, and the optimal precoding/beamforming schemes are designed to enhance the physical layer security performance. Finally, Monte Carlo simulations validate and prove the feasibility of the application of interference alignment technique in the next generation cellular networks under imperfect conditions.