Research On The Covert Communication Theory Based On Full Duplex Receiver

With the rapid development of wireless communication technology,the current society has higher and higher requirements for the security of information transmission.However,due to the broadcast characteristics of wireless communication,there is a risk of interception and attack by illegal eavesdropping parties during the data transmission process.On the other hand,with the increasing maturity of new attack methods,the traditional cryptographic encryption system has been unable to fully guarantee the safe and reliable transmission of information.In response to the increasingly urgent threats to communication security,the application of covert communication technology emerges.Different from the traditional upper layer encryption technology and physical layer security means,covert communication pays more attention to the protection of the transmission process,and uses various optimization techniques to ensure that the transmission signal is not detected by illegal eavesdroppers.As an emerging secure communication technology,covert communication mainly focuses on the analysis of system capacity and channel uncertainty,but these studies rarely consider the influence of location distribution on covert performance,and illegal eavesdropping in practical scenarios The location information of the party is often not known accurately.Therefore,in order to improve the achievability of covert communication technology in practical applications,it is urgent to carry out theoretical research on location analysis-oriented covert systems.This paper studies the model construction,performance analysis,and resource optimization problems in covert communication theory.Aiming at the problem of limited transmission capacity of the basic covert communication model,this paper proposes a scheme that uses full-duplex receivers to transmit artificial noise to assist in the realization of covert communication.Based on different assumptions about the location distribution of illegal eavesdroppers,a covert implementation model in corresponding scenarios is proposed.Furthermore,according to the robust optimization technology,the optimal detection conditions of the eavesdropper and the optimization direction to improve the system performance are given.The details are as follows:(1)For the scenario where illegal eavesdroppers are randomly distributed in a limited area,a movable full-duplex transmitter is introduced to realize the concealment process.According to the classical robust optimization principle,the optimal detection conditions of the eavesdropper are derived.Furthermore,a joint optimization framework for covert communication is designed.System effective throughput.The system optimization strategy under different conditions is given by classification and discussion,and the influence of full-duplex receiver interference power and eavesdropper distribution area on system performance is verified by numerical simulation.(2)For the scenario where the location of the illegal eavesdropping party obeys a twodimensional Poisson distribution,a multi-antenna transmitter is introduced to realize the covert communication process.First,the distribution location and detection threshold of the illegal eavesdropping party when the optimal detection conditions are determined are determined,and then the two-stage robust optimization is carried out.The technology optimizes the system predetermined transmission rate,multi-antenna transmitter transmission power,and full-duplex receiver interference power to maximize system connection throughput.And the consistency of the simulation results and the theoretical results is proved by experiments,and the scheme can maximize the connection throughput of the system while ensuring the concealment.This conclusion enriches the basic theoretical system of full-duplex covert communication.