Coupled-Theoretical-Model-Based on-Demand Quantum Secured Future Fronthaul Architecture Over Hybrid Core Fibers

In this paper, we propose a coupled theoretical model used for noise processing at nodes of hybrid core fiber with single core fiber (SMF)-multicore fiber (MCF), and intra-core noises and inter-core noises are considered in the model. Then, we propose an on-demand quantum secured future fronthaul architecture and a channel allocation algorithm over hybrid core fibers, and the proposed coupled theoretical model is used to calculate the noises in architecture. For fronthaul optical signals, wavelength modes and the number of transceiver modules in the distributed unit (DU) can be dynamically adjusted according to requirements, and the function of load aggregation is adopted. For quantum key distribution (QKD), quantum signals are transmitted in a dedicated core, and wavelength-time multiplexing is adopted to increase the number of quantum secured base station (BSs) while improving wavelength utilization. Finally, simulation results show that proposed channel allocation algorithm can suppress noise about 60% compared to First-Fit. The architecture can save up to 83.3% modules in 7-core feeder fiber, and it is feasible to support 128 BSs. The experimental and simulation results show that the proposed coupled theoretical model matches well with the experimental results, and the quantum bit error rates in experiment are both lower than 2.5%. The results show that the architecture has the advantages of allocating time-space-frequency resources on-demand, saving power consumption, and expanding the number of users. Therefore, it provides a feasible solution for future optical fronthaul networks secured by QKD.