Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:2009.09550

Physical-Layer Security for Two-Hop Air-to-Underwater Communication Systems With Fixed-Gain Amplify-and-Forward Relaying

Lou, Yi, Ruofan Sun, Julian Cheng, Songzuo Liu, Feng Zhou, Gang Qiao

Published Sep 21, 2020• 9 citations
arXivHTMLPDF

Abstract

We analyze a secure two-hop mixed radio frequency (RF) and underwater wireless optical communication (UWOC) system using a fixed-gain amplify-and-forward (AF) relay. The UWOC channel is modeled using a unified mixture exponential-generalized Gamma distribution to consider the combined effects of air bubbles and temperature gradients on transmission characteristics. Both legitimate and eavesdropping RF channels are modeled using flexible $α-μ$ distributions. Specifically, we first derive both the probability density function (PDF) and cumulative distribution function (CDF) of the received signal-to-noise ratio (SNR) of the mixed RF and UWOC system. Based on the PDF and CDF expressions, we derive the closed-form expressions for the tight lower bound of the secrecy outage probability (SOP) and the probability of non-zero secrecy capacity (PNZ), which are both expressed in terms bivariate Fox's $H$-function. To utilize these analytical expressions, we derive asymptotic expressions of SOP and PNZ using only elementary functions. Also, we use asymptotic expressions to determine the optimal transmitting power to maximize energy efficiency. Further, we thoroughly investigate the effect of levels of air bubbles and temperature gradients in the UWOC channel, and study nonlinear characteristics of the transmission medium and the number of multipath clusters of the RF channel on the secrecy performance. Finally, all analyses are validated using Monte Carlo simulation.

DOI
10.48550/arxiv.2009.09550

Related papers

Secrecy Outage Analysis of Two-Hop Decode-and-Forward Mixed RF/UWOC Systems

Yi Lou, Ruofan Sun, Julian Cheng +2 more

The secrecy performance is analyzed for a two-hop mixed radio frequency (RF)/underwater wireless optical communication (UWOC) system using a decode-and-forward (DF) relay. All RF and UWOC links are modeled by the$\alpha -\mu $and exponential-generalized Gamma distributions, respectively. We first derive the expressions of a lower bound of secrecy outage probability in closed-form, and these expressions are used to derive asymptotic expressions in simple functions at high signal-to-noise ratio. Moreover, based on the asymptotic expressions, we can numerically determine a suboptimal transmit power for a wide variety of RF and UWOC channel conditions. All analyses are validated using Monte Carlo simulation.

arXiv:2009.00328•IEEE Communications Letters•Feb 12, 2021•40 citations

Dual-Hop Mixed RF-UOW Communication System: A PHY Security Analysis

Elmehdi Illi, Faissal El Bouanani, Daniel Benevides da Costa +2 more

In this paper, the secrecy performance of a dual-hop mixed radio-frequency/underwater optical wireless communication (RF-UOWC) system is investigated. The considered system consists of one single antenna source node (S) communicating with one destination node (D), considered as the legitimate receiver, through an amplify-and-forward relay node equipped with multiple antennas for reception. Specifically, the relay receives the incoming signal from S via an RF link, applies maximal-ratio combining technique, amplifies the output combined signal with either a fixed gain or variable gain, and then forwards it to the destination via an UOWC link. The transmission protocol is performed under the eavesdropper's attempt to overhear the RF link (i.e., S-R). We derive exact closed-form expressions for the system's average secrecy capacity and the intercept probability in terms of Meijer's G-function as well as the univariate and bivariate Fox's H-functions. A complexity analysis is also performed to analyze the evaluation time of the derived analytical formulas as well as Monte Carlo simulation method complexity. Our derived analytical formulas present an efficient tool to depict the impact of some system and channel parameters on the secrecy performance, namely, the number of relay antennas, the number of eavesdropping nodes, relay gain, fading severity of RF links, and water turbulence severity of the UOWC link.

IEEE Access•Jan 1, 2018•54 citations

Security at the Physical Layer Over GG Fading and mEGG Turbulence Induced RF-UOWC Mixed System

A. S. M. Badrudduza, Md. Najib Ibrahim, S. M. Riazul Islam +4 more

With the rapid evolution of communication technologies, high-speed optical wireless applications under the water surface as a replacement or complementary to the conventional radio frequency (RF) and acoustic technologies are attracting significant attention from the researchers. Since underwater turbulence (UWT) is an inevitable impediment for a long distance underwater optical wireless communication (UOWC) link, mixed RF-UOWC is being considered as a more feasible solution by the research community. This article deals with the secrecy performance of a variable gain relay-based mixed dual-hop RF-UOWC framework under the intercepting attempt of a potential eavesdropper. The RF link undergoes Generalized Gamma (GG) fading distribution, whereas the UOWC link is subjected to mixture Exponential Generalized Gamma (mEGG) distribution. The eavesdropper is capable of wiretapping via a RF link that also experiences the GG fading. The secrecy analysis incorporates the derivations of closed-form expressions for strictly positive secrecy capacity, average secrecy capacity, and exact as well as lower bound of secrecy outage probability in terms of univariate and bivariate Meijer's G and Fox's H functions. Based on these expressions, impacts of heterodyne and intensity modulation/direct detection techniques along with weak, moderate, and severe UWT conditions due to air bubbles, temperature, and salinity gradients are quantified. To the best of authors' knowledge, the proposed model is the first of its kind that addresses the secrecy analysis of a temperature gradient RF-UOWC system along with air bubbles, as opposed to the existing models that considered thermally uniform scenarios only. Finally, the derived expressions are verified via Monte-Carlo simulations.

IEEE Access•Jan 1, 2021•48 citations

Secrecy Outage Performance Analysis of Dual-Hop RF-UOWC Systems

Hongjiang Lei, Chen Zhu, Imran Shafique Ansari +2 more

This article investigates the secrecy performance of a dual-hop radio frequency-underwater optical wireless communication (RF-UOWC) system. Using stochastic geometry theory, the eavesdroppers are modeled as a Poisson point process distribution, and RF and UOWC links are modeled as Nakagami-$m$and mixture exponential-generalized gamma distributions, respectively. Firstly, we derive the statistical laws of signal-to-noise ratio for illegitimate receivers in both colluding and noncolluding scenarios and legitimate receivers when amplify-and-forward and decode-and-forward relaying strategies are employed. Subsequently, closed-form expressions for the lower bound of secrecy outage probability (SOP) are derived. Finally, analytical results are verified via Monte Carlo simulation results, and the effects of channel and system parameters on secrecy outage performance of dual-hop systems are analyzed. Numerical results demonstrate that environmental parameters, such as temperature and bubble levels, exhibit an important impact on the SOP of RF-UOWC systems.

IEEE Systems Journal•Aug 8, 2022•15 citations

On the Secrecy Performance of Mixed RF/UOW Communication System

Elmehdi Illi, Faissal El Bouanani, Daniel Benevides da Costa +2 more

In this paper, the secrecy performance of a dual-hop mixed radio-frequency/underwater optical wireless communication (RF/UOWC) system is investigated. The considered system consists of one single antenna source node (S) communicating with one destination node (D), considered as the legitimate receiver, through the help of one amplify-and-forward (AF) relay node R equipped with multiple antennas for reception. Specifically, the relay receives the incoming signal from S via an RF link, applies maximal-ratio combining (MRC) technique, amplifies the output combined signal with a fixed gain, and then forwards it to D via a UOWC link. The transmission protocol is performed under the eavesdroppers' attempt to overhear the RF link (i.e., S -R). We derive an exact closed-form expression for the secrecy intercept probability (IP) in terms of the Fox's H-function, or in terms of the Meijer's G-function as a particular case. The derived secrecy performance metric is evaluated in terms of various channel and system parameters, and corroborated by Monte-Carlo simulation method. Our derived analytical formulas present an efficient tool to highlight the impact of some system and channel parameters on the secrecy performance.

IEEE Globecom Workshops (GC Wkshps)•Dec 1, 2018•12 citations

Effective Secrecy Throughput Analysis Over Underwater Wireless Optical Channel

Auntora Roy Chowdhury, Milton Kumar Kundu, A. S. M. Badrudduza

The advantages of physical layer security (PLS) have led researchers to apply this in various communication scenarios, such as radio frequency (RF) communication, free space optical (FSO) communication, and underwater optical wireless communication (UOWC). This paper analyzes the PLS, specifically the effective secrecy throughput (EST) over the mixture exponential generalized gamma (mEGG) UOWC channel link in the presence of a passive eavesdropper. To achieve this goal, firstly the closed-form expression of the secure outage probability (SOP) of the system is derived, and using that SOP expression, the final EST expression is found considering the underwater turbulence (air bubble and temperature gradient) as well as two different detection scenarios (heterodyne detection (HDD) & intensity modulation/direct detection(IM/DD)) in terms of Meijer-G functions. Moreover, the average secrecy capacity (ASC) of such a scenario is also exploited in this work. Finally, the expressions are verified through Monte-Carlo simulation.

International Conference on Electrical, Computer and Communication Engineering•Feb 23, 2023•5 citations
We analyze a secure two-hop mixed radio frequency (RF) and underwater wireless optical communication (UWOC) system using a fixed-gain amplify-and-forward (AF) relay. The UWOC channel is modeled using a unified mixture exponential-generalized Gamma distribution to consider the combined effects of air bubbles and temperature gradients on transmission characteristics. Both legitimate and eavesdropping RF channels are modeled using flexible α−μα-μα−μ distributions. Specifically, we first derive both the probability density function (PDF) and cumulative distribution function (CDF) of the received signal-to-noise ratio (SNR) of the mixed RF and UWOC system. Based on the PDF and CDF expressions, we derive the closed-form expressions for the tight lower bound of the secrecy outage probability (SOP) and the probability of non-zero secrecy capacity (PNZ), which are both expressed in terms bivariate Fox's HHH-function. To utilize these analytical expressions, we derive asymptotic expressions of SOP and PNZ using only elementary functions. Also, we use asymptotic expressions to determine the optimal transmitting power to maximize energy efficiency. Further, we thoroughly investigate the effect of levels of air bubbles and temperature gradients in the UWOC channel, and study nonlinear characteristics of the transmission medium and the number of multipath clusters of the RF channel on the secrecy performance. Finally, all analyses are validated using Monte Carlo simulation.
The secrecy performance is analyzed for a two-hop mixed radio frequency (RF)/underwater wireless optical communication (UWOC) system using a decode-and-forward (DF) relay. All RF and UWOC links are modeled by the$\alpha -\mu $and exponential-generalized Gamma distributions, respectively. We first derive the expressions of a lower bound of secrecy outage probability in closed-form, and these expressions are used to derive asymptotic expressions in simple functions at high signal-to-noise ratio. Moreover, based on the asymptotic expressions, we can numerically determine a suboptimal transmit power for a wide variety of RF and UWOC channel conditions. All analyses are validated using Monte Carlo simulation.
In this paper, the secrecy performance of a dual-hop mixed radio-frequency/underwater optical wireless communication (RF-UOWC) system is investigated. The considered system consists of one single antenna source node (S) communicating with one destination node (D), considered as the legitimate receiver, through an amplify-and-forward relay node equipped with multiple antennas for reception. Specifically, the relay receives the incoming signal from S via an RF link, applies maximal-ratio combining technique, amplifies the output combined signal with either a fixed gain or variable gain, and then forwards it to the destination via an UOWC link. The transmission protocol is performed under the eavesdropper's attempt to overhear the RF link (i.e., S-R). We derive exact closed-form expressions for the system's average secrecy capacity and the intercept probability in terms of Meijer's G-function as well as the univariate and bivariate Fox's H-functions. A complexity analysis is also performed to analyze the evaluation time of the derived analytical formulas as well as Monte Carlo simulation method complexity. Our derived analytical formulas present an efficient tool to depict the impact of some system and channel parameters on the secrecy performance, namely, the number of relay antennas, the number of eavesdropping nodes, relay gain, fading severity of RF links, and water turbulence severity of the UOWC link.
With the rapid evolution of communication technologies, high-speed optical wireless applications under the water surface as a replacement or complementary to the conventional radio frequency (RF) and acoustic technologies are attracting significant attention from the researchers. Since underwater turbulence (UWT) is an inevitable impediment for a long distance underwater optical wireless communication (UOWC) link, mixed RF-UOWC is being considered as a more feasible solution by the research community. This article deals with the secrecy performance of a variable gain relay-based mixed dual-hop RF-UOWC framework under the intercepting attempt of a potential eavesdropper. The RF link undergoes Generalized Gamma (GG) fading distribution, whereas the UOWC link is subjected to mixture Exponential Generalized Gamma (mEGG) distribution. The eavesdropper is capable of wiretapping via a RF link that also experiences the GG fading. The secrecy analysis incorporates the derivations of closed-form expressions for strictly positive secrecy capacity, average secrecy capacity, and exact as well as lower bound of secrecy outage probability in terms of univariate and bivariate Meijer's G and Fox's H functions. Based on these expressions, impacts of heterodyne and intensity modulation/direct detection techniques along with weak, moderate, and severe UWT conditions due to air bubbles, temperature, and salinity gradients are quantified. To the best of authors' knowledge, the proposed model is the first of its kind that addresses the secrecy analysis of a temperature gradient RF-UOWC system along with air bubbles, as opposed to the existing models that considered thermally uniform scenarios only. Finally, the derived expressions are verified via Monte-Carlo simulations.
This article investigates the secrecy performance of a dual-hop radio frequency-underwater optical wireless communication (RF-UOWC) system. Using stochastic geometry theory, the eavesdroppers are modeled as a Poisson point process distribution, and RF and UOWC links are modeled as Nakagami-mmmand mixture exponential-generalized gamma distributions, respectively. Firstly, we derive the statistical laws of signal-to-noise ratio for illegitimate receivers in both colluding and noncolluding scenarios and legitimate receivers when amplify-and-forward and decode-and-forward relaying strategies are employed. Subsequently, closed-form expressions for the lower bound of secrecy outage probability (SOP) are derived. Finally, analytical results are verified via Monte Carlo simulation results, and the effects of channel and system parameters on secrecy outage performance of dual-hop systems are analyzed. Numerical results demonstrate that environmental parameters, such as temperature and bubble levels, exhibit an important impact on the SOP of RF-UOWC systems.
In this paper, the secrecy performance of a dual-hop mixed radio-frequency/underwater optical wireless communication (RF/UOWC) system is investigated. The considered system consists of one single antenna source node (S) communicating with one destination node (D), considered as the legitimate receiver, through the help of one amplify-and-forward (AF) relay node R equipped with multiple antennas for reception. Specifically, the relay receives the incoming signal from S via an RF link, applies maximal-ratio combining (MRC) technique, amplifies the output combined signal with a fixed gain, and then forwards it to D via a UOWC link. The transmission protocol is performed under the eavesdroppers' attempt to overhear the RF link (i.e., S -R). We derive an exact closed-form expression for the secrecy intercept probability (IP) in terms of the Fox's H-function, or in terms of the Meijer's G-function as a particular case. The derived secrecy performance metric is evaluated in terms of various channel and system parameters, and corroborated by Monte-Carlo simulation method. Our derived analytical formulas present an efficient tool to highlight the impact of some system and channel parameters on the secrecy performance.
The advantages of physical layer security (PLS) have led researchers to apply this in various communication scenarios, such as radio frequency (RF) communication, free space optical (FSO) communication, and underwater optical wireless communication (UOWC). This paper analyzes the PLS, specifically the effective secrecy throughput (EST) over the mixture exponential generalized gamma (mEGG) UOWC channel link in the presence of a passive eavesdropper. To achieve this goal, firstly the closed-form expression of the secure outage probability (SOP) of the system is derived, and using that SOP expression, the final EST expression is found considering the underwater turbulence (air bubble and temperature gradient) as well as two different detection scenarios (heterodyne detection (HDD) & intensity modulation/direct detection(IM/DD)) in terms of Meijer-G functions. Moreover, the average secrecy capacity (ASC) of such a scenario is also exploited in this work. Finally, the expressions are verified through Monte-Carlo simulation.