Third order integrable UHF bandpass filter using active inductors

In this article, an UHF third order bandpass filter based on an high‐Q active inductor (AI) is described and measurement results, performed on a prototype board, are presented and compared with software simulations. The designed AI includes a passive variable phase‐ and amplitude‐compensating network and a highly linear inverting amplifier, forming a gyrator‐C architecture that gives to the filter also frequency and amplitude tuneability proprieties. The fabricated Butterworth filter has a center frequency of 600 MHz and a measured noise figure of 11 dB with a 5 dBm 1‐dB compression point and a 82 dB dynamic range. All passive components values have been chosen to allow the circuit to be completely integrated in a standard IC design. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1426–1429, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26857