高阻带抑制LTCC 滤波器的设计与实现*

提出了一种基于LTCC技术的新型高阻带抑制带通滤波器的实现方法.采用在并联谐振器的圆柱形电感之间引入感性耦合,在高阻带产生一个传输零点,并且能实现非常好的阻带衰减性能.本文对传统的梳状线带通滤波器结构进行改进,利用过孔的寄生电感效应,将过孔用作谐振杆,明显减小了器件的尺寸.并且通过利用空间耦合的寄生效应,实现滤波器的阻带高抑制传输零点,以满足了对特殊频点高抑制的要求.运用该方法设计了中心频率1.65 GHz,通带200MHz,带外2GHz处衰减大于60dBc的五级带通滤波器.实物测试结果和全波电磁仿真结果吻合较好.

Design and Realization of LTCC Bandpass Filterwith High Stopband Rejection

A new implementation method of high stopband rejection bandpass filter based on LTCC technology is proposed. By introducing inductive coupling between cylindrical inductance of parallel resonators, the filter produces one transmission zero in the high stopband and can achieve a very good stopband attenuation performance. The structure of the traditional comb-line bandpass filter has been improved in the paper, using the parasitic inductance effects of vias, which is usedas a resonator rod, greatly reducing the size of the device. And through the use of space coupling parasitic to achieve the highstopband inhibit transmission zero of the filter, it meets the requirements of special frequency high rejection. A five cavityband pass filter with a pass band of 200MHz at 1. 65GHz designed in this way , the attenuation at 2GHz was more than60dBc. The evaluation results show a good match with the fullwave electromagnetic simulation.