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International Conference on Optical Network Design and Modeling (ONDM)

WDM-Enabled Classical/Quantum Coexistence During Full Daylight for Converged Fiber/FSO Networks

Aristeidis Stathis, Argiris Ntanos, Panagiotis Toumasis, Nikolaos K. Lyras, Giannis Giannoulis, H. Avramopoulos

Published May 6, 2024• 2 citations
Publisher

Abstract

We propose a WDM-enabled optical architecture in support of optimized classical/QKD coexistence over the deployed fiber/FSO infrastructure for 6G communications. A detailed analysis of 4-channel C-band WDM Classical/Quantum coexistence over deployed fiber/FSO links was conducted, showcasing the feasibility of QKD links for intra-campus connections in both mediums revealing QBER values (<3.2%) under daylight conditions.

DOI
10.23919/ondm61578.2024.10582761

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We propose a WDM-enabled optical architecture in support of optimized classical/QKD coexistence over the deployed fiber/FSO infrastructure for 6G communications. A detailed analysis of 4-channel C-band WDM Classical/Quantum coexistence over deployed fiber/FSO links was conducted, showcasing the feasibility of QKD links for intra-campus connections in both mediums revealing QBER values (<3.2%) under daylight conditions.
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In this work, we demonstrate the coexistence system integrating commercial-grade optical transport network equipment from a pilot production line with silicon photonics based quantum key distribution operating in the C-band over a 10 km hollow-core fiber link. The system simultaneously achieves a secure key rate of 2 kbps and supports classical communication at 80λ×100 Gbps capacity with 11 dBm launch power, establishing a new benchmark for practical quantum-classical network integration. This implementation represents a significant advancement toward deployable, high-performance quantum-secured communication infrastructure.