一种DGS带状线低通滤波器的设计

A Design of Stripline DGS Loss-Pass Filter

缺陷地结构(DGS)具有单极点低通特性、慢波效应以及等效高特性阻抗的特性,可以有效地改善低通滤波器的特性。本文针对经典的哑铃状DGS单元进行分析,讨论了其尺寸对频率特性的影响。另外,本文还利用这种结构设计了一种截止频率为3.6GHz的七阶带状线低通滤波器,与传统的高低阻抗带状线低通滤波器相比,其具有矩形系数更高,阻带范围更宽,尺寸更小的优点。这种DGS带状线低通滤波器可应用于基板层间走线和布局有限的场合。

Defective ground structure(DGS)has the characteristics of unipolar point low pass characteristic,slow wave effect and equivalent high characteristic impedance,which can effectively improve the characteristics of low pass filter.This paper analyzes the classical dumbbell-shaped DGS unit and discusses the influence of its size on the frequency characteristics.In addition,this paper also uses this structure to design a seventh-order stripline low-pass filter with a cut-off frequency of 3.6 GHz.Compared with the traditional stripline high-low impedance low-pass filter,it has the advantages of higher rectangular coefficient,wider stopband range and smaller size.The DGS stripline low pass filter can be used in the applications where the wiring between substrates is limited and the layout is limited.