In this article, the secrecy performance of a hybrid radio frequency (RF)/visible light communication (VLC) system is studied. In this hybrid system, the source node (i.e., Alice) transmits information to the relay node via the outdoor RF link. Nakagami-m fading and path loss are considered for the RF link. The relay node includes an outdoor component and an indoor component, which are connected by using a wired medium. The outdoor component receives and recovers information by using the decode-and-forward (DF) relaying scheme and then transmits it to the indoor component. The indoor component then converts the received electrical signal into an optical signal by using a light-emitting diode. A legitimate receiver (i.e., Bob) deployed on the floor receives the optical signal. An eavesdropper (i.e., Eve) deployed in the RF or VLC link wiretaps the confidential information. In this study, we use the secrecy outage probability (SOP) and the probability of strictly positive secrecy capacity (SPSC) to evaluate the system performance. We then obtain the closed-form expression for a lower bound on the SOP and an exact closed-form expression for the probability of SPSC when the RF and VLC links are wiretapped, respectively. Numerical results are presented to validate the accuracy of our derivations. We further discuss the effects of the noise standard deviation, the equivalent threshold of the signal-to-noise ratio, and the floor radius on the system secrecy performance when the VLC link is eavesdropped upon. For the case when the RF link is eavesdropped upon, the impacts of the distance between Alice and the relay, the path loss exponent, the fading factor, and the distance between Alice and Eve on secrecy performance are also provided.
This letter studies the security performance of hybrid radio frequency (RF) and visible light communication (VLC) system. In this hybrid system, the source node (i.e., Alice) transmits information to the relay node via the outdoor RF link. Nakagami-m fading and path loss are considered for the RF link. The relay using the decode-and-forward (DF) relaying scheme. A legitimate receiver (Bob) arranged on the floor receives the optical signal. An eavesdropper (Eve) deployed in VLC link wiretaps the confidential information. In this paper, secrecy outage probability (SOP) is used to assess the performance of the system. We derive the closed expression of the lower bound of SOP when VLC link is wiretapped. Numerical results to validate the accuracy of our derivation.
Abstract In this paper, we investigate the secrecy performance of a dual-hop hybrid radio frequency–visible light communication (RF–VLC) system in which we consider a single source antenna ( S ) transmitting data signals via RF channel through decode and forward (DF) relay ( R ) toward an authorized receiving antenna ( D ) at the destination via VLC channel. In this system, we assume that the eavesdropper ( E ) attempts to eavesdrop the RF channel ( S , R ) during transmission of the signal. The relay decodes the incoming RF signal into corresponding optical signal and retransmits toward destination via VLC channel ( R , D ). The RF and VLC channels of the hybrid system are modelled using generalized-K fading distribution and generalized Lambertian radiant intensity distribution respectively. Also the receiver is assumed to be mobile and its mobility is defined by random waypoint (RWP) model. The channels statistics are used to derive the exact analytical expressions for average secrecy capacity and intercept probability in terms of Meijer’s G-function. The derived closed form analytical expressions are the efficient tool to illustrate the impact of variation in different channel parameters on the secrecy performance, namely, shadowing parameters of RF channel, field of view (FOV), semiangle, and the order of Lambertian emission of the VLC channel. Further, numerical analysis is carried out to support the mathematical analysis of the RF–VLC hybrid system.
In this paper, a cooperative hybrid visible light communication (VLC)-radio frequency (RF) system with spatially random terminals is considered. Especially, a source node (
S) with a group of light-emitting diode (LED) lamps transmits information bits to a destination (
D), which is located out of
S’s coverage area, via a relay node (
R).
Ris equipped with a photodetector and an antenna to set up a VLC link between
Sand
R, and a radio frequency (RF) link between
Rand
D, respectively. Meanwhile, an eavesdropper (
E) equipped with a photodetector and an antenna tries to overhear the information delivery over VLC and RF links. Also, diversity receiving scheme is considered at
E, while the same modulation scheme is considered over both VLC and RF links. Furthermore, decode-and-forward scheme is adopted at
Rto process and forward the received VLC signals. By employing stochastic geometry, we first characterize the probability density function and cumulative distribution function of the received signal-to-noise-ratio over both VLC and RF links, while considering the randomness of the locations of both
R,
E, and
D. Then, the secrecy performance of the target system is studied by deriving the approximated expressions for the secrecy outage probability under various cases. Finally, the proposed analytical models are verified via Monte-Carlo simulations.
Over recent years, visible light communications (VLC) has gained prominence as a promising alternative to traditional RF communication, offering advantages in terms of bandwidth and security. This paper investigates the physical-layer security for a practical indoor VLC system where the positions of a legitimate receiver (Bob) and an eavesdropper (Eve) are considered to be random within their circular receiving planes. For this system model, the statistics of the VLC channel gains are obtained using which, closed-form expressions for the secrecy outage probability are derived. The analytical results, validated through Monte Carlo simulations, demonstrate the impact of key system parameters, namely signal-to-noise ratio, Bob and Eve relative positions, and the target secrecy rate on the SOP performance.
In this paper, the secrecy performance of the physical layer security (PLS) of the hybrid free-space optical/radio frequency (FSO/RF) communication system is analyzed. The transmission protocol of the considered system is performed under the eavesdropper's attempt to overhear the RF link between the transmitter and legitimate receiver of the hybrid system. The FSO link is characterized by Málaga-M distribution while the RF links are modeled by Nakagami-m distribution. The two practical eavesdropping modes considered in this paper include: colluding and non-colluding. Exact closed-form expressions for the system's secrecy outage probability (SOP), the asymptotic of the SOP (SOP∞), the probability of strictly positive secrecy capacity (SPSC), the average secrecy capacity (ASC), and the asymptotic of the ASC (ASC∞), are specifically derived under the influence of both eavesdropper modes. Our derived analytical expressions present an efficient tool to investigate the impact of some channel parameters on the secrecy performance, namely the fading severity of the RF links, atmospheric turbulence severity, pointing error of the FSO link, number of eavesdroppers, and the power of the eavesdropper links. The results show that the increase of the eavesdroppers' number under both modes profoundly degrades the considered system secrecy performance. The accuracy of the numerical results obtained is validated by Monte-Carlo simulations.
This paper evaluates the secrecy outage probability of a hybrid radio frequency (RF) and visible light communication (VLC) network in the presence of an eavesdropper.We assume that data is transmitted over the RF and VLC links following a proposed multiplexing scheme in which the data sent by the source is split with a certain allocation ratio.Furthermore, the legitimate and eavesdropper users are assumed to have multihoming capabilities, so that they are able to receive data from both RF and VLC access points, simultaneously.We derive integral-form exact expression, as well as a closedform asymptotic expression for the secrecy outage probability and validate them via Monte Carlo simulations.Our results show that multiplexing the information signal by both links leads to an enhancement of the secrecy performance since it opportunistically takes advantages of the best characteristics of both domains.