A compact UWB bandpass filter with ultra narrow notched band and competitive attenuation slope

Author

Luo, Xiaohua ; Qian, Hua ; Ma, Jiaxin ; Ma, Kwan-Liu ; Yeo, Kiat Seng

Author_Institution

University of Electronic Science and Technology of China, Chengdu, China

fYear

2010

fDate

23-28 May 2010

Firstpage

1

Lastpage

1

Abstract

A compact ultra-wideband (UWB) bandpass filter with notched band is proposed using the microstrip/coplanar waveguide (CPW) composition structure and quarter wavelength (λ/4) embedded CPW resonator in this paper. Basic quasi-elliptic response and multi-mode UWB operation are achieved through a λ/4 CPW detached-mode resonator (DMR) and broadside-coupled transitions from microstrip to CPW. To avoid the interferences in the UWB passband, two identical λ/4 CPW resonators embedded in the DMR are employed to obtain a narrow notched band. To further improve the selectivity, two microstrip short-stubs are introduced to provide an additional observable transmission zero at 1.86 GHz, which leads to enhanced roll-off characteristic at the lower end of the passband. As such, the proposed filter exhibits a 10 dB notched band fractional bandwidth (FBW) smaller than 2.26% and a competitive attenuation slope with 94.34 dB/GHz in the lower and 67.92 dB/GHz in the upper transition bands, respectively.

Keywords

Attenuation; Band pass filters; Coplanar waveguides; Filtering theory; Interference; Microstrip filters; Microstrip resonators; Passband; Resonator filters; Ultra wideband technology;

fLanguage

English

Publisher

ieee

Conference_Titel

Microwave Symposium Digest (MTT), 2010 IEEE MTT-S International

Conference_Location

Anaheim, CA

ISSN

0149-645X

Print_ISBN

978-1-4244-6056-4

Electronic_ISBN

0149-645X

Type

conf

DOI

10.1109/MWSYM.2010.5516879

Filename

5516879