A Quasi Elliptic Function 1.75–2.25 GHz 3-Pole Bandpass Filter With Bandwidth Control

Author

Chiou, Yi-Chyun ; Rebeiz, Gabriel M.

Volume

60

Issue

2

fYear

2012

Firstpage

244

Lastpage

249

Abstract

A three-pole microstrip combline filter with a center frequency of 1.75-2.25 GHz and a tunable bandwidth of 70-100 MHz is presented. In this design, an extra transmission zero is created using a non-adjacent resonator coupling, and is placed on the lower side of the passband to improve the filter selectivity. The filter bandwidth is also tuned by controlling the non-adjacent resonator coupling. The measured S -parameters, third-order intercept point and power handling, for different center frequencies and bandwidths, are presented and with good agreement with simulations. This topology is simple to implement and requires only one additional tunable component between the first and third resonator for bandwidth control.

Keywords

UHF filters; band-pass filters; comb filters; elliptic filters; microstrip filters; resonator filters; S-parameters; bandwidth 70 MHz to 100 MHz; bandwidth control; filter selectivity; frequency 1.75 GHz to 2.25 GHz; microstrip combline filter; non-adjacent resonator coupling; power handling; quasi elliptic function 3-pole bandpass filter; third-order intercept point; transmission zero; Bandwidth; Couplings; Filtering theory; Frequency measurement; Insertion loss; Resonant frequency; Tuning; Bandpass filter; combline resonator; elliptic-function response; non-adjacent resonator coupling; tunable bandwidth filter; tunable filter;

fLanguage

English

Journal_Title

Microwave Theory and Techniques, IEEE Transactions on

Publisher

ieee

ISSN

0018-9480

Type

jour

DOI

10.1109/TMTT.2011.2178260

Filename

6126068