Research On Key Technologies Of High Secure Transmission In UAV Communication Networks

With the rapid development of wireless communication,the fifth generation of mobile communication technology leads the new generation of communication technology with the characteristics of high speed,low delay and large-scale machine communication.The proliferation of mobile data traffic brings severe challenges to the existing mobile communication system.On the other hand,the widespread popularity of Internet of things devices brings high-quality service experience to users,but the limited battery capacity of mobile devices is difficult to provide long-term high-quality services.In this paper,due to the characteristics of UAV Communication,which can provide line of sight transmission and the channel broadcast characteristics of information and energy transmission at the same time,the information security transmission technology based on physical layer security mechanism is studied,and the optimal resource allocation strategy of joint optimization of UAV transmission power and trajectory is designed.The specific contents can be summarized as follows:In the UAV-assisted wireless information and energy transmission system,in order to ensure the safe communication between UAV and information receiver,this paper aims to maximize the average secrecy rate of information receiving user,and the constraints are the energy demand of the eavesdropper,the starting and ending location of UAV,the speed and power constraints,and the design of joint optimization of UAV trajectory and transmitting power resources.Based on the iterative optimization algorithm,the closed form expression of UAV's transmitting power is derived.The simulation results show that the security performance of the joint optimization algorithm is better than the other two benchmark schemes.The above information security transmission system of UAV assisted information and energy transmission is based on the premise that the location information of the eavesdropper is completely known.However,due to the inaccurate location information of the eavesdropper in the actual scene,there is a compromise in the system security performance.In order to make the research more based on the actual situation,this paper also studies the high robust information security transmission problem of information and energy transmission assisted by UAV with multiple eavesdroppers.Specifically,the position error of eavesdroppers is subject to the boundary error model.The constraint conditions are the energy demand of eavesdroppers in the worst situation and the position,speed constraint and power constraint of UAV,and a robust resource allocation scheme is designed to jointly optimize the trajectory and power of UAV.Based on alternating optimization algorithm and convex optimization theory,the nonconvex problem is transformed into convex optimization problem by using successive convex approximation.The simulation results show that the security performance of the legitimate users of the robust resource allocation scheme is better than that without considering the robustness.In conclusion,the resource allocation algorithm studied in this paper will provide important theoretical and practical reference for UAV assisted energy collection system.