Study On Low Crosstalk And Bend Insensitive Multi-core Fiber

Due to the explosion of information on the Internet,optical communication network is under tremendous pressure.Although the transmission capacity of single mode single core fiber(SM-SCF)has been close to 100Tb/s with the improvement of manufacturing technology,it also cannot satisfy the growing capacity demand.Multi-core fiber is proposed as a solution to expand transmission capacity.Thanks to the reduction of the core pitch and outer cladding thickness,crosstalk and bending loss are becoming the most important issues affecting performance of multi-core fiber.Considering low crosstalk and low bending loss characteristics,a dual-cladding trench assisted heterogeneous multi-core fiber is proposed by analyzing the influence of parameters on crosstalk and bending loss.The main research work is summarized as follows:1.The model of heterogeneous multi-core fiber is established based on finite element method to analyze the effects of fiber parameters including bending radius,core pitch,core radius and the relative refractive-index difference between core and cladding on crosstalk and bending loss.It provides a theoretical basis for designing low crosstalk and bending insensitive multi-core fiber.2.The dual cladding fiber is studied by analyzing the influence of the inner cladding parameters on the mode field area.Based on the analysis result,two different core structures are designed with the mode field area of 10O?m2.Next,by comparing the advantages of the three core arrangement methods,the single-ring arrangement is adopted for fiber design.Then the number of cores is calculated to be 6 by setting the cladding diameter to 150?m.Finally,the effects of trench parameters on effective refractive index difference,crosstalk and RCMF are discussed in detail for the optimization scheme of low crosstalk and bending resistance.3.A dual-cladding trench-assisted heterogeneous multi-core fiber is proposed in this paper to achieve large mode field area of each core about 97?m2 and low bending loss less than 3.96×10-5B/m.The crosstalk value at 1550nm wavelength can even reach-89dB/100km.