W波段片上基片集成波导高选择性滤波器研究

W-Band High-Selective BPF Based on On-Chip SIW Technology

本文研究了通过引入负耦合结构为复平面虚轴增加一对零点以改善传统四阶滤波器的选择特性,通过设计刻蚀不同的耦合槽来比较不同耦合结构对滤波器幅频带外抑制度的改善效果。文章在先前已有的普通片上SIW四阶94GHz滤波器的基础上,为使其拓扑结构产生异相耦合,进一步地分别在两个非相邻耦合腔之间刻蚀了一种“H”形和一种为“弓”字形的两种不同槽结构,为原来均为磁耦合的拓扑添加一对电耦合。最后仿真结果成功地验证了所提出的方法,在保持其94GHz工作频率的同时实现了传输零点的产生,进而增加了滤波器的选择性。

In this paper,a negative coupling structure is introduced to add a pair of zeros to the virtual axis of the complex plane to improve the selection characteristics of the traditional fourth-order filter,and the effect of different coupling structures on the out-of-band suppression of the filter is compared by designing and etching different metal slots.On the basis of the existing SIW fourth-order 94GHz filter on a common chip,two different slot structures,an“H”shape and a“bow”shape,are etched respectively between two non-adjacent coupling cavities in order to produce heterophase coupling,and a pair of electrical coupling is added to the original magnetic coupling topology.Finally,the simulation results successfully verify the proposed method,which achieves the generation of transmission zero while maintaining the 94GHz operating frequency,thus increasing the selectivity of the filter.