In this paper, we investigate the physical layer secrecy performance of a single-input single-output system that consists of single antenna devices and operates in the presence of a single antenna passive eavesdropper over dissimilar fading channels. In particular, we consider two scenarios in terms of dissimilar fading channel arrangements: 1) The legal/illegal channels are subject to Rayleigh/Rician fading, respectively; 2) The legal/illegal channels are subject to Rician/Rayleigh fading, respectively. Specifically, analytical expressions for the probability of the existence of a non-zero secrecy capacity and the secrecy outage probability are derived by using statistical characteristics of the signal-to-noise ratio. Numerical results are provided for selected scenarios to illustrate applications of the developed analytical expressions.
In this paper, we investigate the physical layer secrecy performance of a single-input single-output system that consists of single antenna devices and operates in the presence of a single antenna passive eavesdropper over dissimilar fading channels. In particular, we consider two scenarios in terms of dissimilar fading channel arrangements: 1) The legal/illegal channels are subject to Rayleigh/Rician fading, respectively; 2) The legal/illegal channels are subject to Rician/Rayleigh fading, respectively. Specifically, analytical expressions for the probability of the existence of a non-zero secrecy capacity and the secrecy outage probability are derived by using statistical characteristics of the signal-to-noise ratio. Numerical results are provided for selected scenarios to illustrate applications of the developed analytical expressions.
In this paper, we investigate the physical layer secrecy performance of a multi-input single-output system. The system consists of multiple antennas at transmitter and single antenna at receiver in the presence of a passive eavesdropper with single antenna over dissimilar fading channels. On the assumption that legal channel is subject to Rayleigh fading while illegal channel undergoes Hoyt fading, expressions for the existence probabilities of secrecy capacity and secrecy outage are derived by using statistical characteristics of signal-to-noise ratio. Analytical results are verified by Monte-Carlo simulations.
In the perspective of information-theoretical security, inspired by the heterogeneity between legal and illegal channels, we consider the physical layer secrecy performance of a novel system model with a single antenna employed for both the transmitter and legal receiver, in the presence of a multiple antennas passive eavesdropper over dissimilar fading channels, where the legal/illegal channels are subject to Rayleigh/Nakagami-m and Nakagami-m/Rayleigh fading, respectively. We assume that the eavesdropper employs either maximal-ratio combining or selection combining reception in order to benefit from space diversity. Specifically, the exact closed-form expressions of the probability of existence of secrecy capacity and the secrecy outage probability are derived by utilizing statistical characteristics of the signal-to-noise ratio. Moreover, the delightful results reveal that the secrecy performance achieves a greater level when the Nakagami-m fading is supposed on the main link due to the line of sight component. In final, the analytical results are verified by Monte-Carlo simulation.
In this paper, we investigate the secrecy performance of single-input single-output (SISO) system over fading, such that the main channel and the eavesdropper channel are subject to Rician/Nakagami-m fading or Nakagami-m/Rician fading, and derive the analytical expressions of the probability of the existence of the non-zero secrecy capacity and the outage probability of secrecy capacity. Although many authors have analyzed the secrecy performance of SISO system over various fading, the secrecy performance in the cases we assume has not been clarified. Furthermore, the simulation and numerical results show that the results using the approximation between Rician and Nakagami-m fading is insufficient in evaluating those probabilities because of only approximation to main bodies of the probability density function, and that our analyses are valid.
A secure multicasting framework is considered in this paper to investigate the secrecy performance of a single-input multiple-output (SIMO) system in which a single antenna source transmits private message to multiple receivers in the presence of multiple eavesdroppers. All the receivers and eavesdroppers are equipped with multiple antennas. The perfect secrecy is obtained when evasedroppers can not be able to decode any transmitted information. Considering independent and identically distributed (i.i.d) Rician-K fading channels, the mathematical expressions for the probability of non-zero secrecy multicast capacity, the ergodic secrecy multicast capacity and the secure outage probability for multicasting are derived in closed-forms. Numerical results are provided to show the impact of the diversity provided by the multiple antennas at the receivers. In addition, the impact of Rician factor, K on the secrecy capacity and outage behaviour of the proposed multicasting scenario is also demonstrated. The performance analysis includes the Rayleigh fading scenario as a special case of Rician-K fading channel and focuses the performance comparison between Rician-K and Rayleigh fading channels.
This paper investigates the performance of physical layer security (PLS) in fluid antenna-aided communication systems under arbitrary correlated fading channels. In particular, it is considered that a single fixed-antenna transmitter aims to send confidential information to a legitimate receiver equipped with a planar fluid antenna system (FAS), while an eavesdropper, also taking advantage of a planar FAS, attempts to decode the desired message. For this scenario, we first present analytical expressions of the equivalent channel distributions at the legitimate user and eavesdropper by using copula, so that the obtained analytical results are valid for any arbitrarily correlated fading distributions. Then, with the help of Gauss-Laguerre quadrature, we derive compact analytical expressions for the average secrecy capacity (ASC), the secrecy outage probability (SOP), and the secrecy energy efficiency (SEE) for the FAS wiretap channel. Moreover, for exemplary purposes, we also obtain the compact expression of ASC, SOP, and SEE by utilizing the Gaussian copula under correlated Rayleigh fading channels as a special case. Eventually, numerical results indicate that applying the fluid antenna with only one activated port to PLS can guarantee more secure and reliable transmission, when compared to traditional antenna systems (TAS) exploiting maximal ratio combining (MRC) and antenna selection (AS) under selection combining (SC).
This paper studies performance analysis of physical layer security in a Rayleigh fading wiretap channel, where, the main (transmitter-to-legitimate receiver) and eavesdropper (transmitter-to-eavesdropper) channel coefficients are correlated. By exploiting the novel approach called Copula theory, we derive closed-form expressions for average secrecy capacity (ASC), secrecy outage probability (SOP), and secrecy coverage region (SCR). Moreover, to more evaluate the impact of channel correlation, the asymptotic behavior of SOP in high signal-to-noise ratio (SNR) regime and other scenarios is studied, and finally, the analytical results are illustrated numerically under the positive dependence, independence, and negative dependence structures. Based on the insights from this analysis, we found that the effect of correlated fading on the performance of physical layer security can be helpful or harmful in different scenarios, depending on the structure of dependency between the main and eavesdropper channels.