Design of the Compact Tunable Filter With Modified Coupled Lines

Author

Ching-Wen Tang ; Chien-Tai Tseng ; Shih-Chieh Chang

Author_Institution

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

Volume

4

Issue

11

fYear

2014

fDate

Nov. 2014

Firstpage

1815

Lastpage

1821

Abstract

A compact tunable bandpass filter (BPF) with a broad stopband is presented. The proposed filter is composed of two modified coupled lines and one varactor-loaded stub. In terms of measurement, the tunable BPF with the transmission zero within the higher passband skirt has a very wide tuning range, from 0.95 to 1.55 GHz (48%). Moreover, with the return loss > 10 dB, there is a controllable constant passband bandwidth 120 MHz. Furthermore, within the tuning range, the insertion loss is from 2.4 to 2.8 dB and the return loss is > 20 dB.

Keywords

UHF filters; band-pass filters; band-stop filters; varactors; BPF; bandwidth 120 MHz; broad stopband; compact tunable bandpass filter; compact tunable filter; frequency 0.95 GHz to 1.55 GHz; loss 2.4 dB to 2.8 dB; modified coupled lines; transmission zero; varactor-loaded stub; Band-pass filters; Capacitance; Filtering theory; Microstrip; Passband; Varactors; Voltage measurement; Bandpass filter (BPF); modified coupled line; varactor;

fLanguage

English

Journal_Title

Components, Packaging and Manufacturing Technology, IEEE Transactions on

Publisher

ieee

ISSN

2156-3950

Type

jour

DOI

10.1109/TCPMT.2014.2349151

Filename

6891231