Secure Cognitive Radio Communication via Intelligent Reflecting Surface

In this paper, an intelligent reflecting surface (IRS) assisted spectrum sharing underlay cognitive radio (CR) wiretap channel (WTC) is studied, and we aim at enhancing the secrecy rate of secondary user in subject to total power constraint transmitter (ST), interference (IPC) primary receiver (PR) as well unit modulus IRS. Due extra IPC eavesdropper (Eve) are considered, all existing solutions for IRS-assisted non-CR WTC transmission CR without fail work. Therefore, propose new numerical optimize under full primary, users’ state information (CSI) three different cases Eve’s CSI: CSI, imperfect CSI with bounded estimation error, no CSI. To solve difficult non-convex optimization problem, efficient alternating (AO) algorithm proposed jointly beamformer ST phase shift coefficients particular, when optimizing during each iteration AO, a Dinkelbach based solution combination successive approximation penalty convex-concave procedure For case, artificial noise (AN) aided approach adopted help rate. Simulation results show that our design greatly enhance performance compared IRS And positive can be achieved by AN given most realizations case so secure communication also guaranteed. All AO algorithms guaranteed monotonic convergence.