Research On Structure Optimization And Performance Of Splitter In Optical Interconnection

With the rapid development of fiber to the home(FTTH)transmission technology,optical communication systems have many outstanding advantages.For example,low power consumption,high integration density,large bandwidth,mature equipment,and highly immune to EMI,etc.The optical splitter as a kind of passive device can bring fast and efficient transmission of information,which is an important part of FTTH and widely used in optical communication systems.The transmission performance and the integration of the optical splitter requirements are gradually increased with the continuous development of passive optical network.Optical power splitter with low loss and small size has become the current research focus.In this paper,the impact of the Y-branch structural parameters on the device performance are studied by the Beam Propagation Method(BPM).The optimization design analysis is carried out to reduce the losses and sizes.The main contents can be summarized as follows:1.The optical transmission and power distribution of the Y-branch are analyzed based on BPM,and the structure model is established in Rsoft.The impact of three structural parameters(trapezoidal waveguide,transition waveguide and S-bend)on the power transmission performance is studied and analyzed.The insertion loss and polarization dependent loss caused by the changes of three structural parameters in the Y-branch is studied.The loss tolerance analysis of the waveguide width,the waveguide height,the spacing at bifurcation of the S-bend output waveguide and the input optical fields are carried out.And that reduce the deviation between actual process production and simulation design further improve the effect of structural optimization analysis.Accroding to the response surface methodology,the impact of three structural parameters(trapezoidal waveguide,transition waveguide,and S-bend)on insertion loss is analyzed,and the optimal combination of three structural parameters is obtained.The total transmission power of the optimized Ybranch 1×2 optical splitter is 96.60%.2.According to the design principle of the asymmetric Y-branch,the geometric structure model is established,and then three structural parameters which can affect the coupling ratio are analyzed,including the transverse offset of the output waveguide,the length of the S-Bend curved waveguide and the width of output waveguide.The significance of the influence of each structural parameter on the excess loss was obtained by the response surface methodology.Based on the above analysis,an asymmetric Y-branch with adjustable large coupling ratio of 10%:90% to 50%:50% and low excess loss could be obtained.3.The transmission performance of the Y-branch with multiple-channel is studied by using the BPM.Taking four output ports as an example,two planar Y-branch 1×4 optical splitters with tree and Sparkle cascading mode are studied.Besides,two types of 3D 1×4 Ybranches have been designed.The transmission performance of four kinds of structures is compared,and the results show that the single-stage 3D 1×4 optical splitter has the advantages of lower loss and smaller size.