Research On Countermeasure Strategy Based On UAV-assisted Covert Communicatio

As an important component of 5G communication systems,unmanned aerial vehicles(UAVs)are widely used for measuring,storing,forwarding,and processing communication signals due to their high mobility and rapid deployment characteristics,and have become a hot issue in current research.Covert communication,as the main communication method for military activities in 5G communication,has flourished at the technical level.However,apart from the technical level,the existing work rarely analyzes the confrontation process of UAVassisted covert communication from the perspective of strategy.To meet the challenge,this paper introduces game theory to improve the covert throughput and the payoffs of the covert communicator at the strategic level,to further enhance the security of covert communication.The concrete research content can be summarized as follows.Firstly,in response to the problem that existing optimization methods for covert communication strategies are difficult to deal with confrontation process of UAV-assisted covert communication in information symmetric scenarios,a UAV-assisted covert communication model based on the game with asymmetric information is proposed.This model first disguises the interference signal of the UAV as environmental noise to interfere with Willie’s detection and obtain the optimal detection threshold of the detector.Then,the game confrontation process between the covert communicator and the detector is analyzed,and the pure Nash equilibrium strategy and mixed Nash equilibrium strategy of both are obtained,and their existence conditions are further proved.The simulation results show that the optimal communication strategy obtained by this model enhances the security of covert communication while improving covert throughput.Secondly,in response to the problem that existing optimization methods for UAV-assisted covert communication strategies are difficult to deal with confrontation process in asymmetric information,a game model for UAV-assisted covert communication based on the game with asymmetric information is proposed.This model first analyzes the constraints that satisfy Bob’s reliability and Willie’s concealment.Then,the existing conditions of the Bayesian Nash equilibrium strategy in the model are analyzed and proved,and the optimal covert communication strategy is obtained.The simulation results show that the optimal communication strategy obtained by this model enhances the security of covert communication while improving covert throughput.To sum up,the research results of this paper enrich the theoretical research of the covert communication confrontation process and enhance the security of UAV-assisted covert communication.