Enhancing Security in Wireless Channels with Reconfigurable Intelligent Surface

This paper focuses on the security considerations of wireless communication networks with the support of reconfigurable intelligent surfaces (RIS) in the presence of multiple eavesdroppers. Specifically, We employ two distinct RIS setups to enhance link security: one placed between the source and the receivers, and another positioned between the source and eavesdroppers. In particular, simple closed-form analytical expressions of the probability of non-zero secrecy capacity (PNZSC) and secure outage probability (SOP) are derived to illustrate the effects of the key parameters such as the average SNR of channels, the number of reflecting surface elements of RIS, and the number of eavesdroppers. Finally, Monte-Carlo simulation is performed to validate the accuracy of the analytical results.