Performance analysis of IRS-UAV-assisted active jamming receiver against active eavesdropper

Abstract

We propose a secure transmission system in the presence of an illegal user on the ground. Due to the shielding of obstacles, the ground source is unable to directly transmit confidential information to the ground destination. Therefore, the ground source relays the confidential information to the ground destination through a jointly deployed relay system comprising intelligent reflecting surface and unmanned aerial vehicle (IRS-UAV). The illegal user either monitors the legitimate communication link or actively eavesdrops on legitimate information. Consequently, we consider that the destination employs an active jamming strategy to disrupt the eavesdropper’s reception, thereby enhancing the security and covert performance of the legitimate communication. Based on this scenario, we derive approximate expressions for the detection error probability, covert rate, transmission outage probability, and secrecy outage probability, and analyze the corresponding secure and covert performance. Simulations verify the correctness of the derived formulas and determine the optimal parameters for the destination and illegal user. Analysis demonstrates that introducing active interference by the legitimate destination can prevent the warden from detecting the covert communication with absolute certainty. Furthermore, the deployment of an active IRS is shown to significantly enhance the overall security performance of the system. Conversely, active interference by the eavesdropper increases the secrecy outage probability, thereby degrading secure transmission performance.