A varactor-tuned RF filter

Author

Brown, Andrew R. ; Rebeiz, Gabriel M.

Author_Institution

Dept. of Electr. Eng., Michigan Univ., Ann Arbor, MI, USA

Volume

48

Issue

7

fYear

2000

fDate

7/1/2000 12:00:00 AM

Firstpage

1157

Lastpage

1160

Abstract

An electronically tunable filter at 1 GHz is presented in this paper. The filter uses a suspended substrate design and commercially available varactors for filter tuning. The filter has a 60% tuning range from 700 MHz to 1.33 GHz with a low insertion loss (better than 3 dB from 1 to 1.33 GHz). This paper discusses the effects of the varactor series resistance and the electrical length of the distributed resonator on the overall resonator quality factor and filter insertion loss. The input third-order intermodulation product intercept point was measured to be better than 17 dBm across the entire tuning range

Keywords

Q-factor; UHF filters; band-pass filters; circuit tuning; losses; passive filters; resonator filters; varactors; 3 dB; 700 MHz to 1.33 GHz; distributed resonator; electrical length; electronically tunable filter; filter insertion loss; filter tuning; input third-order intermodulation product intercept point; low insertion loss; resonator quality factor; suspended substrate design; varactor series resistance; varactor-tuned RF filter; Band pass filters; Diodes; Fingers; Insertion loss; Magnetic separation; Radar tracking; Radio frequency; Resonator filters; Tuning; Varactors;

fLanguage

English

Journal_Title

Microwave Theory and Techniques, IEEE Transactions on

Publisher

ieee

ISSN

0018-9480

Type

jour

DOI

10.1109/22.848501

Filename

848501