波导带通滤波器

On Waveguide Band-Pass Filter

针对一般平面结构滤波器,如微带线切比雪夫型滤波器所面对的带内插损和带外抑制这一对矛盾,本文使用圆形波导腔体作为谐振器,有效地提高了谐振器的Q值,使在满足带内插损不大于指标要求的前提下,尽量使滤波器的带外抑制提高。另外,在函数类型上使用椭圆函数型,使带外出现有限频率传输零点,进一步提高了带外抑制能力。利用一腔多模,可以在相同的级数要求下,大大减小滤波器的尺寸和重量,可使其能胜任星载通信设备的要求。

Facing the contradiction between the pass - band insertion loss and the stop - band rejection in the planar filter design, in this paper a circular cavity is used as the resonator, and the Q factor of the resonator is considerably increased. The stop - band rejection is increased as much as possible within the confines of the pass - band insertion loss target. In addition, the stop- band rejection can be further increased by using elliptic filter function which has limited frequency transmission zeros. Introducing multi modes in a single cavity can reduce the dimension and weight of the filter considerably compared to the other function filters in the same order so as to meet the requirements in the satellite communication.