A Compact Tunable Notch Filter With Wide Constant Absolute Bandwidth

Author

Ching-Wen Tang ; Wei-Chen Chen

Author_Institution

Dept. of Electr. Eng., Nat. Chung Cheng Univ., Chiayi, Taiwan

Volume

25

Issue

3

fYear

2015

fDate

Mar-15

Firstpage

151

Lastpage

153

Abstract

A compact notch filter with a wide tunable frequency range is developed. This tunable filter is composed of two varactor-tuned resonators, shunted at input/output ports separately, and one quarter-wavelength transmission line connecting two varactor-tuned resonators. By enlarging impedance of the quarter-wavelength transmission line, the proposed tunable filter can obtain a wide and constant absolute bandwidth within the whole tunable frequency band. The measured results show that there is a wide tuning range, 124.3%. In addition, with insertion loss greater than 20 dB, a wide constant absolute bandwidth can be achieved at 450 MHz.

Keywords

circuit tuning; notch filters; resonator filters; transmission lines; varactors; compact tunable notch filter; input-output ports; quarter wavelength transmission line; varactor-tuned resonators; wide constant absolute bandwidth; wide tunable frequency range; Bandwidth; Impedance; Power transmission lines; Transmission line measurements; Tuning; Varactors; Wireless communication; Notch filter; tunable filter; varactor;

fLanguage

English

Journal_Title

Microwave and Wireless Components Letters, IEEE

Publisher

ieee

ISSN

1531-1309

Type

jour

DOI

10.1109/LMWC.2014.2382671

Filename

7004059