中继协同无人机辅助的认知无线电网络安全通信

针对中继协同无人机（UAV）辅助的无线通信网络，提出一种基于认知无线电网络（CRN）的物理层安全通信方案。利用二次发射机协同解码转发中继向目的接收机发送机密消息，将UAV用作移动干扰器发送干扰噪声，以降低窃听者的解码能力。在不影响主用户通信的前提下，通过联合优化UAV的飞行轨迹和发射功率提高系统的平均保密率，采用基于连续凸逼近的算法求解近似凸规划的保密率最大化问题。仿真结果表明，相较于优化功率和优化轨迹这两种传统方案，该方案能够进一步提高CRN系统通信的安全性。

Secure Communication in Cognitive Radio Network Assisted by Cooperative Relay and UAV

This paper proposes a communication scheme that ensures physical layer security based on Cognitive Radio Network(CRN), which is designed for Wireless Communication Networks(WSN) assisted by cooperative relay and Unmanned Aerial Vehicle(UAV).In order to reduce the decoding ability of the eavesdropper, the scheme employs Secondary Transmitter(ST) to coordinate with the Decode and Forward(DF) relay to send confidential messages to the destination receiver, while UAV serve as mobile jammers to transmit interference noise.On the premise of not affecting the primary user communication, the flight trajectories and transmit power of UAV are jointly optimized to improve the average security rate of the system.At the same time, the algorithm based on continuous convex approximation is used to solve the problem of maximum secrecy rate of approximate convex programming.The simulation results show that the proposed scheme can achieve higher system security than the traditional schemes based on power optimization or trajectory optimization.