源与负载感性交叉耦合的小型介质滤波器

为了提高滤波器的阻带衰减，研究了源与负载感性交叉耦合的小型介质滤波器。首次提出一种新概念：将源和负载看作准谐振器。以贴片电感作为源与负载之间、源与第二个谐振器之间的交叉耦合元件，两个准谐振器和两个介质谐振器可构成级联四节(CQ)，一个准谐振器和两个介质谐振器可构成级联三节(CT)。分析了传输零点的位置，详细讨论了这种滤波器结构的设计方法。采用介电常数为80的介质陶瓷组装了3个两级介质滤波器，并进行测试，结果表明传输零点的个数和位置与仿真设计相符合。滤波器的体积小，均为14 mm×6.5 mm×10 mm。

Compact Dielectric Filters With Inductive Cross Coupling Between Load and Source

In order to improve the stopband attenuation of the filter, a compact dielectric filter with inductive cross coupling between the load and the source has been developed.A new concept that the source and the load can be regarded as pseudo resonator is proposed for the first time. An inductor is used as the cross coupling element between the source and the load or the source and the second resonator.Two pseudo resonators together with two dielectric resonators can form a cascaded quadruplet (CQ),two dielectric resonators together with a pseudo resonator can form a cascaded triplet (CT).The locations of the transmission zeros are analyzed and the design of the proposed filters are discussed in details. Three second order filters made of dielectric ceramics with dielectric constant of 80 are fabricated and measured.The results show the measured numbers and positions of transmission zeros have a good agreement with the simulation. The fabricated filters have compact volumes of 14 mm×6.5 mm×10 mm.