Secure Outage Analysis of RIS-Assisted Communications With Discrete Phase Control

卷:72

Article

关键词: RECONFIGURABLE INTELLIGENT SURFACES;    SECRECY PERFORMANCE ANALYSIS;    PHYSICAL-LAYER SECURITY;    REFLECTING SURFACE;    WIRELESS COMMUNICATION;   

DOI  :  10.1109/TVT.2022.3224967

来源: SCIE

【 摘 要 】

This correspondence investigates a reconfigurable intelligent surface (RIS)-assisted wireless communication system with security threats. The RIS is deployed to enhance the secrecy outage probability (SOP) of the data sent to a legitimate user. By deriving the distributions of the received signal-to-noise-ratios (SNRs) at the legitimate user and the eavesdropper, we formulate, in a closed-form expression, a tight bound for the SOP under the constraint of discrete phase control at the RIS. The SOP is characterized as a function of the number of antenna elements, $N$, and the number of discrete phase choices, $2<^>{b}$. It is revealed that the performance loss in terms of SOP due to the discrete phase control is ignorable for large $N$ when $b \geq 3$. In addition, we explicitly quantify the SOP loss when binary phase shifts, i.e., $b =1$, are utilized. It is found that increasing the number of RIS elements by 1.6 times provides the same SOP as that of an RIS with continuous-valued phase shifts. Numerical simulations are conducted to verify the accuracy of these theoretical observations.

【 授权许可】

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