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 this channel subject to total power constraint at secondary transmitter (ST), interference power constraint (IPC) at primary receiver (PR) as well as unit modulus constraint at IRS. Due to extra IPC and eavesdropper (Eve) are considered, all the existing solutions for enhancing secrecy rate of IRS-assisted non-CR WTC as well as enhancing transmission rate in IRS-assisted CR channel without eavesdropper fail in this work. Therefore, we propose new numerical solutions to optimize the secrecy rate of this channel under full primary, secondary users' channel state information (CSI) and three different cases of Eve's CSI: full CSI, imperfect CSI with bounded estimation error, and no CSI. Simulation results show that our proposed solutions for the IRS-assisted design greatly enhance the secrecy performance compared with the existing numerical solutions with and without IRS under full and imperfect Eve's CSI. And positive secrecy rate can be achieved by our proposed AN aided approach given most channel realizations under no Eve's CSI case so that secure communication also can be guaranteed. All of the proposed AO algorithms are guaranteed to monotonic convergence.

翻译：本文研究的是智能反射表面(IRS)协助的频谱共享下层认知无线电(CR)窃听频道(WTC),我们的目标是提高该频道第二用户的保密率,条件是二级发报机(ST)、初级接收机(PR)的干扰力限制(IPC)以及IRS的单位模模量限制(单元模量限制)。由于IPC和Eve窃听器(Eve)额外增加,所有现有的提高IRS协助的非CR WTC保密率以及提高IRS协助的CR频道在这项工作中不出现窃听器失灵的情况下的传输率的解决方案。因此,我们提出了新的数字解决方案,以优化该频道在全面初级、二级用户频道国家信息(CSI)以及Eve CSI的三个不同案例中的保密率。由于IPCS和EV(E)不完善的估算错误,以及没有CSI(E)的模拟结果显示,我们为IRS协助设计而提出的解决方案与现有的数字解决方案相比,在IRS和IRS不失灵监听器不失灵的情况下,在这项工作中可以保证AS Eveal AS AS Eveoration AL Arealations realations requiquest requilations (C) (Civation) (A) (A) (A) (A) (A) (A) (A) (A) (A) AL) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A)) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A) (A)