Artificial Noise Injection–Based Secrecy Improvement for FSO Systems

• Main Authors: Aman Sikri, Aashish Mathur, Manav Bhatnagar, Georges Kaddoum, Prakriti Saxena, Jamel Nebhen
• Format: Article
• Language: English
• Published: IEEE 2021-01-01
• Series: IEEE Photonics Journal
• Subjects: <inline-formula xmlns:ali="http://www.niso.org/schemas/ali/1.0/" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"> <tex-math notation="LaTeX">$\mathcal {M}$</tex-math> </inline-formula> turbulence model; artificial noise (AN); free -space optical communication (FSO); physical layer security; pointing errors
• Online Access: https://ieeexplore.ieee.org/document/9360442/

In this paper, an artificial noise (AN) injection technique is incorporated in a free-space optical (FSO) communication system with the aim of enhancing the secrecy performance of the system. An intensity modulated direct detection (IM/DD) FSO link which is subjected to Malaga (<inline-formula><tex-math notation="LaTeX">$\mathcal {M}$</tex-math></inline-formula>) distributed turbulence with pointing errors is considered in this paper. The performance of FSO systems is evaluated by deriving novel closed-form expressions for the secrecy outage probability (SOP), strictly positive secrecy capacity (SPSC), and throughput of the system. By formulating a constrained optimization problem, we discuss an optimal power allocation strategy for throughput maximization in the considered system. It is shown through the results that the proposed technique is very effective in improving the secrecy performance of FSO systems.