Title :
A Low Loss X-Band Quasi-Elliptic Ferroelectric Tunable Filter
Author :
Courrèges, Stanis ; Li, Yuan ; Zhao, Zhiyong ; Choi, Kwang ; Hunt, Andrew ; Papapolymerou, John
Author_Institution :
Sch. of Electr. & Comput. Eng. (ECE), Georgia Inst. of Technol., Atlanta, GA
fDate :
4/1/2009 12:00:00 AM
Abstract :
A compact high quality factor four-pole X-band tunable quasi-elliptic bandpass filter is presented in this letter. The filter is enabled by high-Q ferroelectric barium strontium titanate capacitors and open-loop resonators. The central frequency of 8.35 GHz and the frequency tuning range of 500 MHz (6%) are achieved with a dc bias voltage of 30 V. The selective filter has a fractional 1 dB bandwidth ranging from 5.5% up to 7.3%. The measured insertion loss and return loss are 5.7-3.5 dB and 10.2-7.9 dB, respectively, with a dc bias range of 0 to 30 V. To the best of our knowledge, this is the best analog tunable performance and selectivity in X-band.
Keywords :
Q-factor; band-pass filters; barium compounds; circuit tuning; elliptic filters; ferroelectric capacitors; microstrip filters; microwave filters; resonator filters; strontium compounds; BaSrTiO3; X-band quasi-elliptic ferroelectric tunable filter; four-pole X-band tunable quasi-elliptic bandpass filter; frequency 8.35 GHz; high-Q ferroelectric barium strontium titanate capacitors; loss 10.2 dB to 7.9 dB; loss 5.7 dB to 3.5 dB; microstrip tunable filter; open-loop resonators; voltage 30 V; Barium strontium titanate (BST) capacitors; micro-electro-mechanical systems (MEMS);
Journal_Title :
Microwave and Wireless Components Letters, IEEE
DOI :
10.1109/LMWC.2009.2015494
