应用缺陷地结构设计低通滤波器  

Designing Lowpass Filter Using Defected Ground Structure

作　　者：高初[1] 王蕴仪[1] 

机构地区：[1]东南大学无线电工程系毫米波国家重点实验室,南京210096

出　　处：《微波学报》2007年第2期51-54,共4页Journal of Microwaves

基　　金：国家自然科学基金资助项目(60071018)

摘　　要：对缺陷地结构(DGS)实现的等效均匀传输线提出了一种简单有效的由S参数求其特性阻抗和有效相对介电常数的方法。而后比较了缺陷地结构和微带线的特性阻抗和有效介电常数随频率变化的规律。最后,应用缺陷地结构设计了两个Chebyshev低通滤波器,并进行了制作和测试。所得滤波器与采用微带线设计的相同参数的低通滤波器相比,阻带最大衰减有超过5dB的改善,并避免了实现高阻抗微带线的工艺困难。In this paper, a simple and effective method to extract characteristic impedance and effective relative permittivity of equivalent even transmission line realized by defected ground structure has been presented. Then, the variation of characteristic impedance and effective relative permittivity with frequency of defected ground structure are compared with those of microstrip. Finally, two Chebyshev lowpass filters employed defected ground structure have been designed, fabricated and tested. It shows more than 5dB improvement in maximum stopband attenuation compared to the same designs using microstrip. Moreover, fabrication difficulty for high impedance microstrip has been avoided.

关 键 词：缺陷地结构 微带线 低通滤波器 特性阻抗 有效相对介电常数 

分 类 号：TN713.4[电子电信—电路与系统]