Enhancing Design and Performance Analysis of Satellite Entanglement-Based CV-QKD/FSO Systems

Abstract

This paragraph of the first footnote will contain support information, including sponsor and financial support acknowledgment."ABSTRACT Satellite QKD/FSO systems, which facilitate quantum key distribution (QKD) over freespace optical (FSO) links between satellites and ground stations, present a promising pathway toward achieving global security in upcoming sixth-generation (6G) wireless communications. Our study focuses on a superior type of these systems, the satellite EB/CV-QKD/FSO, which utilizes the continuousvariable (CV) method for quantum state representation and the entanglement-based (EB) scheme for QKD implementation. We propose the use of optical phase-shift keying (QPSK) signaling and dualthreshold/heterodyne detection (DT/HD) receivers to bolster the reliability and feasibility of satellite EB/CV-QKD/FSO systems. Closed-form expressions for key system performance metrics are derived using improved channel modeling. Numerical results are presented to showcase the effects of channel impairments on the system performance. We also provide recommendations for optimal system setup parameters, aiming to enhance performance.INDEX TERMS Free-space optics (FSO), quantum key distribution (QKD), entanglement-based (EB) scheme, continuous-variable QKD (CV-QKD), optical phase-shift keying (QPSK) signaling, heterodyne detection (HD) receivers.