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

Optical Engineering

Secrecy analysis of a free-space laser communication system with a coherent main channel

Manuel Prasanna Kalaimani, Harishankar Ramachandran

Published Jun 2, 2023• 2 citations
Publisher

Abstract

Physical layer security of a free-space optical (FSO) communication link is investigated for certain eavesdropping scenarios in which the eavesdropper exploits the divergence of the transmitted laser beam, which is subject to atmospheric turbulence, to compromise the security of the transmission link. A solution for physical layer security in which the legitimate receiver is positioned to receive only the coherent component of the transmitted laser beam is proposed. The irradiance fluctuations are modeled with separate distributions for the coherent and non-coherent components of the transmitted beam, corresponding to the main channel and the eavesdropper’s channel, respectively. Complete secrecy analysis of this setup is presented, and closed form expressions of the probability of strictly positive secrecy capacity, average secrecy capacity, and secrecy outage probability are derived. The analytical results are verified by Monte-Carlo simulations. Secrecy performance for worst-case scenarios corresponding to an adversary with powerful resources to capture all of the leaked information is explored. Results are analyzed for different turbulence regimes, and it was found that secure communication is possible even in the region of strong turbulence.

DOI
10.1117/1.oe.62.6.068101

Related papers

Secrecy outage probability analysis in a free-space optical system based on partially coherent beams through anisotropic non-Kolmogorov turbulent atmosphere

Hongyu Wu, Jing Ma, Pengzhen Guo +4 more

In this paper, the secrecy outage probability of a partially coherent beam free-space optical communication system considering the combined effect of anisotropic non-Kolmogorov strong turbulent atmosphere and the eavesdropper’s position is investigated. The Fisher–Snedecor distribution is chosen to model the atmospheric turbulence because it is not only suitable for weak to strong turbulence conditions but is also mathematically simple. Based on the fading channel model and the generalized pointing error model, we derive analytical expressions for the lower bounded secrecy outage probability. Also, we obtain asymptotic closed-form expression at a high signal-to-noise regime. The obtained expressions are corroborated by Monte Carlo simulations. The calculation results based on the analytical expressions show that increasing the source coherence parameter makes the secrecy interruption probability performance first better and then worse for a given condition, and an optimal value is observed. The anisotropic coefficient and power law have a positive effect on the secrecy outage probability of the free-space optical communication system. Under the given conditions, the performance of the secrecy outage probability is significantly improved by the divergent beam, although the increased spot size at the receiver makes it easier for eavesdroppers to tap the link. The secrecy outage probability performance deteriorates as the vertical component of Bob, the jitter variance, and the refractive index structure constant increase.

Journal of the Optical Society of America B•Apr 6, 2022•5 citations

On Secure Free-Space Optical Communications Over Málaga Turbulence Channels

Mohammad Javad Saber, Seyed Mohammad Sajad Sadough

The security issue is investigated from a physical layer perspective in the context of free-space optical (FSO) communications. More precisely, the performance of secure FSO link with intensity modulation/direct detection over Málaga (M) atmospheric turbulence channels that accounts for pointing errors is addressed in this letter. The closed-form expressions for the average secrecy capacity, the secrecy outage probability and the strictly positive secrecy capacity are derived by considering the specific nature of FSO channels modeled by the general M distribution. Monte-Carlo simulations are provided to verify the accuracy of our derivations.

IEEE Wireless Communications Letters•Feb 20, 2017•119 citations

Physical Layer Security Performance Analysis of Hybrid FSO/RF Communication System

Wafaa Mohammed Ridha Shakir

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.

IEEE Access•Dec 31, 2020•37 citations

On Secure Communications for FSO Systems Over Generalized Turbulence Channels

Wafaa Mohammed Ridha Shakir, Ruwaida A. A. Abdul Kareem

With the continued development of optical wireless communications, the security performance of free space optical (FSO) communications is the most crucial aspect that should receive significant attention. Despite the fact that FSO communications are considered more secure than radio frequency systems, their link performance degrades due to some environmental factors such as atmospheric turbulence, fog, and non-zero boresight pointing errors. The combined effect of these factors on the secrecy performance of FSO communication systems over the generalized Malaga- M fading channel is investigated in this paper. This work assumes a more realistic eavesdropping scenario in which both legitimate and unauthorized receivers are located on the same receiving plane. Secrecy outage probability and strictly positive secrecy capacity are expressed in exact closed-form expressions in this work. The results show that the FSO system has acceptable secrecy performance in moderate and light fog, with potential reach distances ranging from hundreds of meters to a few kilometers. Monte-Carlo simulations are used to verify the numerical results.

IEEE International Symposium on Measurements & Networking (M&N)•Jul 18, 2022•10 citations

Secrecy performance analysis in the FSO communication system considering different eavesdropping scenarios

Hongyu Wu, Dongpeng Kang, Junrong Ding +4 more

In this paper, we numerically study the secrecy performance of the free-space optical (FSO) system by considering different eavesdropping scenarios. More precisely, we considered three possible eavesdropping scenarios for Eve : 1) Eve is between Alice and Bob ; 2) Eve and Bob are in the same receiving plane; 3) Eve is behind Bob . We adopt the Málaga ( M )-distribution channel to model atmospheric turbulence due to the presence of link blockage while considering the non-zero boresight pointing error and path loss. To do so, we obtain a novel probability density function (PDF) and cumulative distribution function (CDF) under different eavesdropping scenarios, based on which we derived the secrecy outage probability (SOP) analytical expressions as well as their asymptotic expressions at a high SNR regime. We verified the results using Monte Carlo simulations, which showed that the parameters related to atmospheric turbulence and pointing errors, as well as the location of the eavesdropper, have different effects on different eavesdropping scenarios.

Optics Express•Oct 17, 2022•23 citations

Secrecy Analysis of FSO Systems Considering Misalignments and Eavesdropper’s Location

Phuc V. Trinh, Alberto Carrasco‐Casado, Anh T. Pham +1 more

The use of free-space optical (FSO) systems as secure transmission media has recently attracted research efforts worldwide. However, their secrecy performance may be compromised by the presence of an adversarial eavesdropper. In addition, misalignments between transceivers could severely affect the legitimate FSO channel and increase eavesdropping risks. This paper, for the first time, offers a complete framework to analyze the impact of an eavesdropper's location on the secrecy performance of terrestrial FSO systems under generalized misalignments and atmospheric turbulence conditions. Particularly, the probability density functions (PDFs) of the eavesdropping channel are newly developed and presented in closed-form expressions. Capitalizing on the derived PDFs, secrecy performance metrics in the physical-layer security (PLS) and intensity modulation/direct detection (IM/DD) continuous-variable quantum key distribution (CV-QKD) systems can be analytically analyzed, incorporating all combined effects of the atmospheric turbulence, transceiver misalignments, receiver noises, and the eavesdropper's location. Monte-Carlo (MC) simulations are also implemented to corroborate the analytical results.

IEEE Transactions on Communications•Sep 11, 2020•57 citations
Physical layer security of a free-space optical (FSO) communication link is investigated for certain eavesdropping scenarios in which the eavesdropper exploits the divergence of the transmitted laser beam, which is subject to atmospheric turbulence, to compromise the security of the transmission link. A solution for physical layer security in which the legitimate receiver is positioned to receive only the coherent component of the transmitted laser beam is proposed. The irradiance fluctuations are modeled with separate distributions for the coherent and non-coherent components of the transmitted beam, corresponding to the main channel and the eavesdropper’s channel, respectively. Complete secrecy analysis of this setup is presented, and closed form expressions of the probability of strictly positive secrecy capacity, average secrecy capacity, and secrecy outage probability are derived. The analytical results are verified by Monte-Carlo simulations. Secrecy performance for worst-case scenarios corresponding to an adversary with powerful resources to capture all of the leaked information is explored. Results are analyzed for different turbulence regimes, and it was found that secure communication is possible even in the region of strong turbulence.
In this paper, the secrecy outage probability of a partially coherent beam free-space optical communication system considering the combined effect of anisotropic non-Kolmogorov strong turbulent atmosphere and the eavesdropper’s position is investigated. The Fisher–Snedecor distribution is chosen to model the atmospheric turbulence because it is not only suitable for weak to strong turbulence conditions but is also mathematically simple. Based on the fading channel model and the generalized pointing error model, we derive analytical expressions for the lower bounded secrecy outage probability. Also, we obtain asymptotic closed-form expression at a high signal-to-noise regime. The obtained expressions are corroborated by Monte Carlo simulations. The calculation results based on the analytical expressions show that increasing the source coherence parameter makes the secrecy interruption probability performance first better and then worse for a given condition, and an optimal value is observed. The anisotropic coefficient and power law have a positive effect on the secrecy outage probability of the free-space optical communication system. Under the given conditions, the performance of the secrecy outage probability is significantly improved by the divergent beam, although the increased spot size at the receiver makes it easier for eavesdroppers to tap the link. The secrecy outage probability performance deteriorates as the vertical component of Bob, the jitter variance, and the refractive index structure constant increase.
The security issue is investigated from a physical layer perspective in the context of free-space optical (FSO) communications. More precisely, the performance of secure FSO link with intensity modulation/direct detection over Málaga (M) atmospheric turbulence channels that accounts for pointing errors is addressed in this letter. The closed-form expressions for the average secrecy capacity, the secrecy outage probability and the strictly positive secrecy capacity are derived by considering the specific nature of FSO channels modeled by the general M distribution. Monte-Carlo simulations are provided to verify the accuracy of our derivations.
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.
With the continued development of optical wireless communications, the security performance of free space optical (FSO) communications is the most crucial aspect that should receive significant attention. Despite the fact that FSO communications are considered more secure than radio frequency systems, their link performance degrades due to some environmental factors such as atmospheric turbulence, fog, and non-zero boresight pointing errors. The combined effect of these factors on the secrecy performance of FSO communication systems over the generalized Malaga- M fading channel is investigated in this paper. This work assumes a more realistic eavesdropping scenario in which both legitimate and unauthorized receivers are located on the same receiving plane. Secrecy outage probability and strictly positive secrecy capacity are expressed in exact closed-form expressions in this work. The results show that the FSO system has acceptable secrecy performance in moderate and light fog, with potential reach distances ranging from hundreds of meters to a few kilometers. Monte-Carlo simulations are used to verify the numerical results.
In this paper, we numerically study the secrecy performance of the free-space optical (FSO) system by considering different eavesdropping scenarios. More precisely, we considered three possible eavesdropping scenarios for Eve : 1) Eve is between Alice and Bob ; 2) Eve and Bob are in the same receiving plane; 3) Eve is behind Bob . We adopt the Málaga ( M )-distribution channel to model atmospheric turbulence due to the presence of link blockage while considering the non-zero boresight pointing error and path loss. To do so, we obtain a novel probability density function (PDF) and cumulative distribution function (CDF) under different eavesdropping scenarios, based on which we derived the secrecy outage probability (SOP) analytical expressions as well as their asymptotic expressions at a high SNR regime. We verified the results using Monte Carlo simulations, which showed that the parameters related to atmospheric turbulence and pointing errors, as well as the location of the eavesdropper, have different effects on different eavesdropping scenarios.
The use of free-space optical (FSO) systems as secure transmission media has recently attracted research efforts worldwide. However, their secrecy performance may be compromised by the presence of an adversarial eavesdropper. In addition, misalignments between transceivers could severely affect the legitimate FSO channel and increase eavesdropping risks. This paper, for the first time, offers a complete framework to analyze the impact of an eavesdropper's location on the secrecy performance of terrestrial FSO systems under generalized misalignments and atmospheric turbulence conditions. Particularly, the probability density functions (PDFs) of the eavesdropping channel are newly developed and presented in closed-form expressions. Capitalizing on the derived PDFs, secrecy performance metrics in the physical-layer security (PLS) and intensity modulation/direct detection (IM/DD) continuous-variable quantum key distribution (CV-QKD) systems can be analytically analyzed, incorporating all combined effects of the atmospheric turbulence, transceiver misalignments, receiver noises, and the eavesdropper's location. Monte-Carlo (MC) simulations are also implemented to corroborate the analytical results.