Design And Fabrication Of Space Division Multiplexer/Demultiplexer Based On Bridge Fiber

With the rapid development of Internet technology,traditional single-mode fiber(SMF)communication systems will not be able to meet the rapacity requirement of future network.Space division multiplexing(SDM)technology which based on multi-core fiber(MCF)is a technology with great development potential to increase the capacity of communication systems.Therefore,MCF has been widely studied by scholars at home and abroad.A major challenge for the development of MCFs is to fabricate high-performance MCF multiplexer/demultiplexer(MUX/De-MUX).Through the MUX/De-MUX,the MCF can be connected to SMFs to achieve the input and output of optical signals.In this paper,the MUX/De-MUX of MCF are designed and fabricated.The main research contents of this dissertation are as follows:(1)A fused taper type MCF MUX/De-MUX based on bridge fiber is proposed.Based on the finite element method(FEM),a numerical simulation model of bridge fiber is established.The model field distribution of bridge fiber with different refractive index structure was calculated by using COMSOL Multiphysics with MATLAB,and the coupling loss of MUX/De-MUX is calculated and optimized.(2)The bridge fibers with different refractive index structures are designed for 7-core MCF and 8-core MCF.Through the bridge fiber,the MUX/De-MUX for 7-core MCF and8-core MCF are fabricated successfully.The performance of the fabricated MUX/De-MUX are measured,and the requirements of insertion loss and crosstalk are achieved.(3)The MUX/De-MUX for few-mode multi-core fiber(FM-MCF)are studied.It is suggested to demultiplex the core and the mode independently.Two types of MUX/De-MUX method are proposed: bridge fiber tapering and stacking etched bridge fiber.A few-mode bridge fiber is designed preliminarily which laid the foundation for future work.