Title :
Monolithic narrow-band filter using ultrahigh-Q tunable active inductors
Author :
Lucyszyn, Stepan ; Robertson, Ian D.
Author_Institution :
Dept. of Electr. & Electron. Eng., London Univ., UK
fDate :
12/1/1994 12:00:00 AM
Abstract :
A tunable active inductor is presented where the novel topology enables both the inductance and series resistance to be varied. With a discrete MMIC realization of this active inductor, Q-factors in excess of 15000 have been measured over a wide range of inductance values. Applications for these active inductors include high-performance narrow-band filters, voltage controlled oscillators, and analog phase shifters. Analytical equations for the novel active inductor and a 3-resonator filter are given. The measured performance for a monolithic 2 GHz filter achieves a mean insertion loss of 0.9 dB, passband ripple of ±0.7 dB, with a 3 dB bandwidth of 70 MHz, and an excellent out-of-band rejection which exceeds 50 dB up to 18 GHz
Keywords :
MESFET integrated circuits; Q-factor; UHF filters; active filters; field effect MMIC; inductors; resonator filters; 0.5 μm MESFET process; 0.9 dB; 2 GHz; 3 dB bandwidth; 3-resonator filter; 70 MHz; Q-factors; active filter; analog phase shifters; common source cascode FET arrangement; discrete MMIC realization; inductance; mean insertion loss; monolithic 2 GHz filter; monolithic narrow-band filter; out-of-band rejection; passband ripple; series resistance; ultrahigh-Q tunable active inductors; voltage controlled oscillators; Active inductors; Band pass filters; Electrical resistance measurement; Inductance measurement; MMICs; Narrowband; Phase shifters; Q factor; Topology; Voltage-controlled oscillators;
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on
