A Novel Transition-Included Multilayer Filter

Abstract

A novel transition-included multilayer filter is proposed with the associated electromagnetically coupled transition from conductor-backed coplanar waveguide to stripline designed as a part of the bandpass filter. Specifically, a filter equivalent-circuit model is introduced with the transformer turn ratio to specify the impedance-transformation characteristic of the transition. The proposed transition-included multilayer filter is then designed by simultaneously taking both embedded stripline resonator circuits and associated transitions into consideration. Being designed along with the transition, the implemented filter occupies a size only half of the conventional filter while still achieving the same specifications. The implemented filter does not require bond wires or air bridges, thereby reducing the response shift caused by misalignment in fabrication. Finally, the measurement and simulation results are presented and good agreement between them is observed.