提出了一种基于双微环引起范诺共振效应实现超窄带滤波的微环谐振滤波器，通过泵浦波导和微加热装置使其同时具备有源和可调谐性能。通过耦合模理论，推导了该结构的透射率及超窄带带宽公式，并利用MATALAB软件模拟了在滤波器结构中注入增益对超窄带带宽和滤波器的透过率的影响，以及微环波导的热光效应对滤波器谐振波长的影响。仿真结果表明，在滤波器中注入增益能增大透过率，压缩滤波器的超窄带带宽，且微环波导的热光效应可使谐振波长发生红移或蓝移。

We demonstrate theoretically an active tunable filter with a simple two-coupled-ring structure, which yields very narrow passband based on Fano resonance in the transmission spectra. The active and tunable performances of the microring filter are achieved by the pump waveguide and micro-heating device, respectively. The formulas of the resonant transmission and the ultra narrow pass-band linewidth are derived through the coupled-mode theory. Then, the relationships between the gain and the transmission and linewidth, as well as the thermo-optic effect and the resonance wavelength of the microring waveguide are simulated useing MATLAB, respectively. The numerical calculation and simulation results show that the gain can increase transmittance and compress linewidth of the microring filter. It is also shown that the thermo-optic effect can make the resonant wavelength red shift or blue shift.