A tunable and reconfigurable active filter based on distributed structure concept

Abstract

The filter presented in this article is an active band-pass filter which center frequency and bandwidth can be tuned. It is composed of channels inserted into a distributed structure, and the frequency agility is obtained by activating one or more of them. The concept is validated with measurements realized on a 3-channel prototype structure implemented in a PPH25 GaAs technology. This filter is tunable throughout the X and Ku bands. This first prototype yields encouraging results: the center frequency can be tuned between 9.7 and 14 GHz, with an average gain of 10 dB throughout this range. The filter occupies 13.5 mm2 of area and consumes 10.5 mA per active stage from a 4V supplying voltage. It is designed for wideband and agile receivers.