为改善普通马赫-曾德尔干涉仪(MZI)滤波器的输出性能,采用将双微环谐振器与马赫-曾德尔干涉仪相结合,设计出一种新的滤波器结构。采用信号流程图理论分析得出该结构的传递函数,并对输出端口的透射谱进行数值模拟分析。仿真结果表明,与普通马赫-曾德尔干涉仪滤波器相比,当选择合适的耦合系数,双微环谐振器辅助马赫-曾德尔干涉仪滤波器的透射谱顶部平坦,形状类似于方形,自由光谱范围达到了19nm,锐度因子为1.16,消光比为54dB,品质因子为94.5,滤波性能得到较大改善。详细研究了耦合系数和微环半径对滤波器输出性能的影响。 In order to improve the output performance of an ordinary Mach-Zehnder interferometer (MZI) filter, a novel filter structure is designed by combining a two-microring resonator with a Mach-Zehnder interferometer. The transfer function of the structure was obtained by using the signal flow diagram theory and the numerical simulation of the transmission spectrum of the output port was carried out. The simulation results show that compared with the conventional Mach-Zehnder interferometer filter, when the appropriate coupling coefficient is selected, the transmission line of the dual-microring resonator-assisted Mach-Zehnder interferometer filter has a flat top and a shape similar to the square The spectral range reached 19nm, the sharpness factor was 1.16, the extinction ratio was 54dB, the quality factor was 94.5, and the filtering performance was greatly improved. The effect of coupling coefficient and microring radius on the output performance of the filter is studied in detail.