中文摘要：

采用MgB2超导薄膜材料设计了一个L频段的滤波器。该滤波器采用半开环结构微带谐振腔,产生准椭圆函数响应。滤波器带宽为61 MHz,中心频率为1.75 GHz,带内波纹小于0.1 dB,回波损耗大于18 dB。针对微带滤波器设计过程中出现的中心频率偏移、回波损耗过大等问题提出了解决方法。

英文摘要：

An L- band microstrip filter is designed using MgB2 superconducting film. Semi-open-loop microstrip resonators are utilized to realize the quasi-elliptic function response. The bandwidth of the filter is 61 MHz at 1.75 GHz center frequency, the band ripple is less than 0.1 dB and the retum loss is better than 18 dB. Methods are proposed to solve the problem that the center frequency deviates and the return loss is too high.