| Quantum key distribution(QKD)is currently one of the promising security technologies,which can theoretically guarantee the security of private communication.The QKD process requires the transmission of quantum signals,and simultaneous transmission technology refers to the transmission of quantum signals and classical signals in the same optical fiber,which can reduce deployment costs and promote the deployment of QKD.In the process of simultaneous transmission,quantum signals will be interfered by various noises generated by classical signals,which will degrade the secure key rate(SKR),and there is also a problem of resource competition between quantum signals and classical signals.Whether it is based on single-core fiber or multi-core fiber simultaneous transmission,it will involve the wavelength allocation of quantum signals and classical signals,and multi-core fiber also introduces the problem of core allocation.At present,there are many studies on the allocation of wavelength resources for single-core fibers,but less research on the allocation of space-frequency resources for multi-core fibers(in this paper,space-frequency resources refer to core resources and wavelength resources,respectively).Moreover,the space-frequency resource allocation of the current quantum signals and the classical signals is relatively independent,and the channels on the multi-core fiber are not fully utilized.Only by jointly planning the quantum signals and the classical signals can the optimal effect be achieved.Aiming at the above problems,this paper studies the space-frequency resource allocation for the joint planning of quantum signals and classical signals in the scenarios of independent-core-transmission and mixed-core-transmission.The research contents are as follows:(1)A joint-planned space-frequency resource allocation technique is proposed for independent fiber-core transmission scenario.It includes a distance maximization-based Alternate Core Allocation Algorithm(ACA)and an interleaved Iteration-Based Wavelength Allocation Algorithm(IBWA).In the independent-core-transmission scenario,classical and quantum signals are transmitted independently on different cores.ACA uses the core distance between the classical cores and the quantum cores as the criterion,alternately allocates the classical and quantum cores,and considers the allocation of core resources in a more balanced manner.Based on the idea of alternate iteration.IBWA considers various noises under the interleaved arrangement of classical and quantum channels,updates the interleaved positions of classical and quantum channels through continuous iteration,and jointly considers the wavelength planning of classical and quantum channels.In this scenario,the overall technique is:first use the proposed core allocation algorithm to perform fiber core allocation,and then use the proposed wavelength allocation algorithm to perform wavelength allocation.The simulation results show that the proposed technique can have better secure key rate(SKR)performance in the case of long-distance transmission and high classical signal power.When the transmission distance is 100 km,the classic signal power is 10 mW,and the minimum channel spacing is 50 GHz,under different combinations of channel requirements,compared with the baseline scheme,the proposed scheme can achieve at least 90.35%improvement in SKR in a regular hexagonal 7-core multi-core fiber.(2)A heuristic space-frequency resource allocation technique based on genetic algorithm is proposed for mixed-core-transmission scenario.In the mixed-core-transmission scenario,classical and quantum signals can be transmitted on the same core.Aiming at this problem,this paper adapts and optimizes the genetic algorithm for the space-frequency resource allocation problem in the mixed-core-transmission scenario.Firstly,a space-frequency matrix is designed,which contains the core and wavelength information of the classical channel in the multi-core fiber,and then the rule for modeling chromosome codes according to different spacefrequency matrices are designed.And linking the design of fitness function with SKR and space-frequency resource utilization of classical signals,a heuristic Genetic Algorithm Based Core and Wavelength Allocation(GACWA)technique for joint planning of classical and quantum signals is proposed.When the transmission distance is 100 km and the classic signal power is 10 mW,under different minimum channel spacing conditions,compared with the baseline scheme,the proposed technique can improve the SKR by 11.65%to 154.56%in a regular hexagonal 7-core multi-core fiber. |
