Active tuning of high frequency resonators and filters

Author

Xu, Hui ; Gao, Erzhen ; Ma, Q.Y.

Author_Institution

Dept. of Electr. Eng., Columbia Univ., New York, NY, USA

Volume

11

Issue

1

fYear

2001

fDate

3/1/2001 12:00:00 AM

Firstpage

353

Lastpage

356

Abstract

In this paper, we present a new electromechanical approach of active control of high temperature superconducting (HTS) resonator and filter center frequency. The design of the tunable devices incorporates piezoelectric bender or tube actuator, which acts as a varactor of the resonance circuit, with YBCO thin film on LAO substrate. The resonator has an unloaded Q of over 18,000 at 77 K and a center frequency of 362 MHz and a tuning range of over 20% with unloaded Q over 10,000. By applying different voltages to the piezoelectric bender, we have tuned the resonance frequency over 30% with a good linearity and high Q. Based on this structure, a two-pole HTS bandpass filter was designed, fabricated and tested. The filter has a tunable center frequency from 17 to 20 MHz while maintaining a 2.5% 3dB bandwidth, and an insertion loss of less than 0.5 dB at 77 K

Keywords

Q-factor; barium compounds; circuit tuning; high-temperature superconductors; piezoelectric actuators; radiofrequency filters; superconducting filters; superconducting resonators; superconducting thin films; yttrium compounds; 0.5 dB; 17 to 20 MHz; 362 MHz; 77 K; LAO substrate; Q-factor; YBCO thin film; YBaCuO; active tuning; center frequency; electromechanical control; high temperature superconductor; high-frequency filter; high-frequency resonator; insertion loss; linearity; piezoelectric bender actuator; piezoelectric tube actuator; resonance circuit; varactor; Band pass filters; Circuit optimization; High temperature superconductors; Resonance; Resonant frequency; Resonator filters; Superconducting filters; Temperature control; Tunable circuits and devices; Tuning;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/77.919355

Filename

919355