Title :
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
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;
Journal_Title :
Components, Packaging and Manufacturing Technology, IEEE Transactions on
DOI :
10.1109/TCPMT.2014.2349151
