| Unmanned aerial vehicles(UAVs)has gotten more and more attentions in wireless communication recently attributed to the advantage on cost economics,on-demand deployment and high mobility.UAV can not only be connected to the communication network as a low-altitude mobile user,but also serve as a communication platform to provide services to users.Due to the nature of wireless channels in terms of sharing and broadcasting characteristics,the confidential information could be readily intercepted when UAVs are communicating with ground users,which significantly threatens the information security.In order to ensure the security of confidential information transmission,the cooperative jamming technique has been employed to weaken the transmission rate of the eavesdropping channel and improve the security of the system,which is the most common technology to ensure the physical layer security.Herein,the key results from the current research are summarized as follows:Firstly,the system model of UAV base station and user communication is proposed.Since there are eavesdroppers in the process of communication,the security of UAV communication system is improved by introducing jammer to send other signals to cooperate with eavesdroppers.Secondly,to solve the problem of the maximum transmission rate of eavesdropping channel,this paper assumes that the eavesdropper is the closest to the drone and the farthest from the jammer in a certain circular area.Then,according to the transmission rate of eavesdropper channel,the transmission rate of the system in the worst case is obtained.Thirdly,in order to improve the transmission rate of the system in the worst case,a joint optimization path and power method was proposed.The original optimization problem was divided into the optimization of UAV path,UAV and jammer power,and the iterative algorithm of block coordinate descent and successive convex optimization was adopted to improve the transmission rate of the communication system.Finally,the information security performance in the process of communication between the UAV and the ground is simulated and the simulation results are analyzed.The results from the simulation demonstrated the effectiveness of the proposed algorithm,and the security of communication can be significantly improved. |
