5G X-haul/QKD Multiplexing over Deployed Infrastructure
Aristeidis Stathis, Argiris Ntanos, Panagiotis Kourelias +4 more
With the rise of 5G X-haul networks and emerging infrastructure segments, efficient multiplexing is essential for enabling secure quantum communication alongside classical data. In this work, we present a polarization-encoded Quantum Key Distribution (QKD) system deployed within the C-band over a live 5G network in Athens, demonstrating coexistence of QKD and 5G services on shared infrastructure. Our setup enables simultaneous transmission of 10 Gb/s classical data and QKD raw click rates of 4.3 kbps (22.6 km backhaul) and 51.9 kbps (2.2 km fronthaul). We propose a novel multiplexing approach using high-isolation, commercial-off- the-shelf (COTS) fiber filters and multiplexers, requiring no changes to existing infrastructure. The system achieves Quantum Bit Error Rates (QBER) below 1.5% and expected Secret Key Rates (SKR) of 650 bps and 11.3 kbps for backhaul and fronthaul, respectively, while maintaining uninterrupted 5G performance. This work offers a practical and scalable path for integrating QKD into future quantum-secured mobile networks.
International Conference on Transparent Optical Networks•Jul 6, 2025•0 citations