The Research Of Crosstalk Suspression In Spacial Multiplexing Network

With the development of cloud computing,distributed computing,content distribution and other internet services,the capacity requirements of communication networks are increasing rapidly.However,single-core fiber is getting close to the Shannon limit and will soon be difficult to meet network capacity requirements.Therefore,multicore fiber witch has multiple cores in one cladding is potentially one option for addressing the rapidly growing network needs in the future.While solving the physical limitations of single-core fiber and greatly increasing the network capacity,multi-core optical fibers are also facing new problems,that is,crosstalk between cores.Since the distance between adjacent cores is very close,crosstalk can not be neglected if the same frequency slot is used for propagation.Therefore,how to suppress the crosstalk between the cores in the multi-core optical fiber in the space division multiplexing network influence whether or how much the capacity of the network can be really improved.This paper first introduces the low crosstalk multi-core optical fiber technology(weakly coupled multi-core optical fiber;strongly coupling multi-core optical fiber),including its classification criteria and the characteristics of each.Then the crosstalk evaluation for the main applications of weakly coupled multi-core optical fiber in space division multiplexing is introduced,both the method and formula derived.On this basis,this paper introduces the technology of crosstalk suppression,including trench-assisted multi-core fiber,heterogeneous multi-core fiber and bi-directional polarization fiber.For each technology,the principle of suppressing crosstalk is described,as well as the current research progress and application.In order to further improve the load capacity of the space division multiplexing network and adapt to the future network services,this paper analyzes the difficulties for FM-MCF utilized MIMO-DSP technology will face while applicated in spatial division multiplexing elastic optical networks.Besides the crosstalk suppression technology mentioned above,crosstalk can also be suppressed by advanced route-space-core allocation strategy.This paper also proposed a RSCA strategy based on service priorities.This strategy takes 7-core MCF for simulation.In addition to crosstalk suppression,it also considers the trade-off between throughput and blocking rate,Therefore,the throughput of high-priority services can be improved as much as possible under the condition that the blocking rate is similar.Then the application of this multi-core SDM network is analysed.Finally,an evaluation method which combined principal component analysis and analytic hierarchy process is put forward to analyse the adaptability of multi-core SDM network,especially in smart grid.