Compact microstrip bandpass filter with two transmission zeros based on λ/8 coupled-line sections

Author

Chao-Huang Wu ; Yo-Shen Lin ; Chi-Hsueh Wang ; Chun Hsiung Chen

Author_Institution

Dept. of Electr. Eng., Nat. Taiwan Univ., Taipei, Taiwan

Volume

2

fYear

2005

fDate

4-6 Oct. 2005

Abstract

Compact microstrip bandpass filter with two transmission zeros is proposed based on one-eighth wavelength (λ/8) coupled-line sections. The proposed filter occupies only half of the circuit area of conventional parallel coupled-line bandpass filter, and exhibits good stopband rejection with no repeated passband at twice center frequency. By introducing a cross-coupled shunt inductor, two transmission zeros at upper and lower stopbands may be created without increasing the circuit area. The desired locations of transmission zeros can be adjusted by varying the value of cross-coupled inductance. Specifically, a microstrip coupled-line bandpass filter centered at 2.45 GHz with a 3dB bandwidth of 9.6% and two transmission zeros is implemented.

Keywords

band-pass filters; coupled circuits; microstrip filters; poles and zeros; λ/8 coupled-line sections; 2.45 GHz; compact microstrip bandpass filter; cross-coupled shunt inductor; microstrip coupled-line bandpass filter; transmission zeros; Band pass filters; Bandwidth; Coupling circuits; Filtering theory; Frequency; Inductance; Inductors; Microstrip filters; Passband; Shunt (electrical);

fLanguage

English

Publisher

ieee

Conference_Titel

Microwave Conference, 2005 European

Print_ISBN

2-9600551-2-8

Type

conf

DOI

10.1109/EUMC.2005.1610080

Filename

1610080