Driven by increasing demand for broadband services and access network,Fiber-To-The-House (FTTH) has been intensively investigated for its unlimited bandwidth.With the develop of FTTH,the ultimate goal is to realize the union of CATV,telephone and internet,so triplexer is one of the key components in FTTH.This theisis suggests a novel structure for triplexer, which is more integrated compared to traditional ones.In addition,based on the birefringence material PPESK,polarization dependence problem is effectively solved.First,the basic theories of optical waveguides are thoroughly investigated.The waveguide propagation condition for three-layer symmetric and asymmetric slab waveguides is deduced from Maxwell's equations.Especially,the effective index method for channel waveguides is introduced.In addition,the frequently used numerical simulation method for waveguides——Finite-Difference-Beam-Propagation Method(FD-BPM).All of the work above can shed light on the design and analysis for the triplexer.Then the design and analyze of low insertion Y-branch waveguide based on polymer material PSQ-L is followed.
