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Title: On Secrecy Performance of RIS-Assisted MISO Systems Over Rician Channels With Spatially Random Eavesdroppers
Reconfigurable intelligent surface (RIS) technology is emerging as a promising technique for performance enhancement for next-generation wireless networks. This paper investigates the physical layer security of an RIS-assisted multiple-antenna communication system in the presence of random spatially distributed eavesdroppers. The RIS-to-ground channels are assumed to experience Rician fading. Using stochastic geometry, exact distributions of the received signal-to-noise-ratios (SNRs) at the legitimate user and the eavesdroppers located according to a Poisson point process (PPP) are derived, and closed-form expressions for the secrecy outage probability (SOP) and the ergodic secrecy capacity (ESC) are obtained to provide insightful guidelines for system design. First, the secrecy diversity order is obtained as 2α2 , where α2 denotes the path loss exponent of the RIS-to-ground links. Then, it is revealed that the secrecy performance is mainly affected by the number of RIS reflecting elements, N, and the impact of the number of transmit antennas and transmit power at the base station is marginal. In addition, when the locations of the randomly located eavesdroppers are unknown, deploying the RIS closer to the legitimate user rather than to the base station is shown to be more efficient. Moreover, it is also found that the density of randomly located eavesdroppers, λe , has an additive effect on the asymptotic ESC performance given by log2(1/λe) . Finally, numerical simulations are conducted to verify the accuracy of these theoretical observations.  more » « less
Award ID(s):
2107182 2030029
PAR ID:
10598719
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
IEEE
Date Published:
Journal Name:
IEEE Transactions on Wireless Communications
Volume:
23
Issue:
8
ISSN:
1536-1276
Page Range / eLocation ID:
8357 to 8371
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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