Physical Layer Security Performance of Multi-User Mixed Radio-Frequency/Free-Space-Optics System Based on Optimal...

Area of Science:

• Wireless Communication
• Physical Layer Security
• Optical Communication

Background:

• Mixed radio frequency (RF) and free space optical (FSO) systems offer enhanced data rates and security.
• Physical layer security (PLS) is crucial for mitigating eavesdropping in wireless networks.
• Simultaneous wireless information and power transfer (SWIPT) enables energy harvesting and data transmission.

Purpose of the Study:

• To analyze the physical layer security performance of a multi-user mixed RF/FSO system.
• To investigate the impact of optimal user interference and SWIPT on system security.
• To derive and validate mathematical expressions for secrecy outage probability (SOP) and average secrecy capacity (ASC).

Main Methods:

• Modeling a mixed RF/FSO system with Rayleigh fading (RF) and Fischer-Snedecor F distribution (FSO).
• Implementing a double-hop decode-and-forward (DF) relay scheme with FSO directivity errors.
• Utilizing SWIPT for energy collection and information forwarding, with an optimal user jamming the eavesdropper.
• Deriving closed-form expressions for SOP and ASC, verified by Monte Carlo simulations.

Main Results:

• Closed-form expressions for SOP and ASC were derived and validated.
• Analysis revealed that increased antennas, interference SNR, time allocation, and energy conversion efficiency improve PLS.
• Improved atmospheric channel quality (weather) also significantly enhances system security.

Conclusions:

• The proposed optimal user interference strategy effectively enhances PLS in mixed RF/FSO systems.
• SWIPT integration and careful parameter selection are vital for robust physical layer security.
• The findings provide valuable insights for designing secure and efficient hybrid wireless communication systems.