Abstract: An equalizer circuit for equalizing RF frequencies implemented as an MMIC or MIC having a series of microstrip transmission lines between an RF input terminal and an RF output terminal and having at least one shunt path comprised of a series combination of a FET able to be switched between a conducting state and a nonconducting state and a stud tuner microstrip transmission line, wherein the FET is used as a voltage variable resistor to selectively de-Q the stub tuner and thereby control the depth of the equalization curve. In a modified embodiment, artificial transmission lines which include a plurality of inductive elements and FETs are coupled to each shunt path, wherein the shunt paths may be selectively shorted by changing the state of the FETs, thereby permitting the center frequency of the equalizer circuit to be shifted as well.

Abstract: The present invention is an equalizer circuit for RF frequencies comprising a microstrip transmission line having a stub tuner extending transversely therefrom and further having resistive means coupled to the stub tuner to de-Q the stub tuner, thereby selectively determining an attenuation profile for the equalizer circuit.