IEICE Electronics Express
Online ISSN : 1349-2543
A compact quad-band bandstop filter using dual-plane defected structures and open-loop resonators
Huansheng NingJun WangQingxu XiongHong LiuLingfeng Mao
Author information

2012 Volume 9 Issue 21 Pages 1630-1636


A novel approach for designing a quad-band bandstop filter is proposed by using dual-plane E-shaped defected structures and open-loop resonators coupled to the microstrip line. Through this design, the proposed filter features four conveniently adjusted stopbands, compact size and simple design procedure. The equivalent circuit model of the quad-band bandstop filter is derived before the design procedure is summarized. To facilitate the filter design, an approximate design rule for the resonant frequency of the E-shaped defected structure and the open-loop resonator is presented. As an illustrated example, a quad-band bandstop filter is designed and fabricated. The fabricated filter has four stopbands with center frequency at 2.37/3.52/5.20/5.76GHz and the rejection levels of the stopbands are all better than 31dB, verifying our proposed design concept.

Information related to the author
© 2012 by The Institute of Electronics, Information and Communication Engineers
Previous article Next article