设计了一种基于异质结构的低串扰3-LP模12芯光纤,纤芯采用异质无沟槽辅助的环形折射率分布,结构简单且能增大纤芯的有效模场面积。利用COMSOL软件分析了异质纤芯的芯间串扰、有效模场面积等性能,结果表明,异质纤芯LP01,LP11,LP21模的芯间串扰分别低于-0.78,-0.66,-0.4 dB/km,有效模场面积分别为150,166,200 μm 2。使用方点阵型纤芯排布方式,可实现包层直径约为213.8 μm、相对纤芯复用因子为26.9的低串扰3-LP模12芯光纤设计,为通信容量的升级扩容提供器件支持。

In this paper, a low crosstalk 3-LP mode 12-core fiber based on heterogeneous structure is designed. The core adopts a heterogeneous ring refractive index distribution without trench-assisted structure, which is simple in structure and can increase the effective mode area of the core. COMSOL software is used to analyze the performance of crosstalk and effective mode area of heterogeneous cores. The results indicate that the inter-core crosstalk of the heterogeneous core LP01, LP11, and LP12 modes are lower than -0.78, -0.66, and -0.4 dB/km, respectively, and their effective mode areas are 150, 166, and 200 μm 2, respectively. With a square lattice core arrangement, a low crosstalk 3-LP mode 12-core fiber design with a cladding diameter of about 213.8 μm and a relative core multiplexing factor of 26.9 can be realized, providing device support for the upgrade and expansion of communication capacity.