本文报道一种利用谐振器中缺口位置设计双模带通滤波器的新方法.用这种方法既可以实现具有一对传输零点的双模带通滤波器,也可以实现无传输零点的双模带通滤波器.通过分析缺口位置对谐振器内电场模式分布的影响,建立了双模滤波器的拓扑结构图.利用全波仿真软件,基于不同的缺口位置设计了中心频率为2.05GHz,带宽为100MHz的两种滤波器.实验测试结果和滤波器理论仿真结果相一致.
A new method is introduced for designing microstrip dual-mode bandpass filters by using different notch positions.By using this method,dual-mode bandpass filter with a pair of transmission zeros or with no transmission zeros can be realized.After analyzing the influence of the notch position to the dual modes in the resonator,the topology structure of the dual mode filter is established.Using full-wave EM software,two kinds of filters with center frequency of 2.05GHz and bandwidth of 100MHz are designed based on different notch positions.Both simulated and measured results are in good agreement.