基于折叠型谐振结构的宽带带阻滤波器的设计

Wideband Bandstop Filter Based on Folded Resonator

基于三组折叠型谐振结构设计出一款紧凑宽带带阻滤波器。首先,对折叠型谐振结构的特性进行分析,结果表明,该结构具有传输零点,且该传输零点具有可调节性。之后,通过分析折叠型谐振结构之间的间隔影响,得到较为合适的间距。在此基础上,通过增加另一组折叠型谐振结构的形式,设计得到了宽带带阻滤波器。仿真结果表明,该滤波器的10-d B工作带宽为1.98 GHz。通过仿真优化,得到一款采用三组折叠型谐振结构的宽带带阻滤波器。将该滤波器进行加工并测试,结果表明,滤波器的工作带宽为2.41 GHz。此外,为了进一步说明该结构的滤波特性,我们对其等效电路进行了分析。由于采用了折叠型结构,所以这款滤波器具有小型化的特性。

A compact wideband bandstop filter composed of three pairs of folded resonators is presented.Firstly,analyzing the characterization of one pair of folded resonators it is found that the structure linked with a pair of folded resonators exhibits adjustable transmission zeros.Then,analyzing the effect of the distance between folded resonators an appropriate distance is got.What’s more,through adopting another pair of folded resonators,a wider band bandstop filter is achieved.Simulated results demonstrate that the 10-dB bandwidth is 1.98 GHz.After optimization,a wideband bandstop filter adopting three pairs of folded resonators has been fabricated and measured.The results show that the bandwidth is 2.41GHz.In addition,in order to explain the mechanism of proposed structure,the equivalent circuit is also analyzed.The length and width of structure get reduced owing to the folded shape.