Analyse On Spurious Mode Suppression Of Microring Resonator Filters

Because its compactness and excellent performance, microring resonator has great application potentials in fiber-optic networks. When used as filters or multiplexers, commonly, several rings are serially coupled to get a big free spectrum range. In these structures, spurious modes need to be suppressed and the passbands need to be optimized. Uesing the transfer matrix method, the output characteristics of the serially cascaded dual-microring and three-microring resonators are analyzed in this thesis. The influence of the coupling coefficients on passband width, flatness, and suppression of spurious mode is analyzed in detail. Result shows that there is a compromise relationship between the bandwidth of the passband and the suppression of the spurious modes. For the dual-microring structures, the optimization route is given. For the three-microring situation, four different structures are compared, and the optimization route for the best structure is offered. Work in this thesis may offer a reference to the design of using large microrings to realize large free spectrum range, and to get good pass band character and spurious mode suppression.