Three branch microwave channelized active bandpass filter

In this paper, a three branch channelized active bandpass filter with an elliptical response is presented. All branches are connected through power dividers/combiners allowing signal distribution and combination. The filter consists of a main branch and two auxiliary branches, each of them has a third order Chebyshev filter made out of active inductances based on CMOS operational transconductance amplifiers according to the 0.18μm TSMC technology. The auxiliary branches have each a delay element that creates a 180° phase shift between the responses of the branches leading to transmission zeros in the bandwidth. The simulation results, obtained by means of CADENCE 16.6 Pspice software, show that the filter produces an elliptic narrow band response, centered at 1,13GHz with good frequency performances in terms of scattering parameters and the noise figure.