Physical layer security of HAPS-based space-air-ground-integrated network with hybrid FSO/RF communication

• Main Authors: Bankey, Vinay, Sharma, Shubha, Swaminathan, R., Madhukumar, A. S.
• Other Authors: School of Computer Science and Engineering
• Format: Article
• Language: English
• Published: 2023
• Subjects: Engineering::Computer science and engineering; Gamma-Gamma Distribution; Physical Layer Security
• Online Access: https://hdl.handle.net/10356/170679
• Institution: Nanyang Technological University

In this article, we study the physical layer security performance of a downlink space-air-ground-integrated network (SAGIN), where a satellite communicates with the ground user/destination via a high-altitude-platform-station-based relay in the presence of an eavesdropper. In particular, we propose to use hybrid free-space optical (FSO)/radio frequency (RF) transmission to enhance the security of the considered system. Herein, the FSO and RF links are assumed to experience Gamma-Gamma and Shadowed-Rician distributions, respectively. Specifically, we derive exact and asymptotic expressions of secrecy outage probability for the considered SAGIN by employing intensity modulation/direct detection. We provide the numerical and simulation results to validate our analysis.