Integration of C-Band Polarization-Encoded QKD Over Deployed 5G X-Haul Infrastructure
Year: 2026
Type: article
Abstract: With the evolution of 5G X-haul connections and the emergence of new infrastructure segments, the need for efficient multiplexing schemes is paramount to support secure quantum communications alongside classical traffic. This study addresses this need by demonstrating successful coexistence of QKD and 5G services over existing X-haul infrastructure, with simultaneous transmission of 10 Gb/s classical data alongside C-band single photons, achieving raw click rates of 4.3 kbps and 51.9 kbps over 22.6 km backhaul (BH) and 2.2 km fronthaul (FH) fiber links, respectively. We introduce a practical multiplexing scheme based on high-isolation, fiber-based filters and multiplexers, enabling the seamless integration of the QKD transmitter and receiver into both BH and FH links without modifying the existing X-haul infrastructure. Experimental results demonstrate continuous and stable operation achieving average QBER values of 4.7% and 2.6%, yielding calculated Secret Key Rates (SKRs) of 650 bps and 6.8 kbps for quantum-secured BH and FH links, respectively, while also maintaining uninterrupted 5G service. Finally, it is investigated whether these SKR are sufficient to meet the requirements for AES-256 encryption for securing the X-haul data exchange. This work provides a practical approach to integrating QKD within deployed 5G X-haul connections, supporting future quantum-secured mobile communications.
Source: Journal of Lightwave Technology
Institution: National Technical University of Athens
Language: English
Subfield: Artificial Intelligence
Field: Computer Science
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $2,645
Funder: European Commission
OpenAlex ID: W7168217943