Modeling of Multilayer MMIC Coplanar Waveguide Low Pass Filter for Cellular Application

Abstract

In the early development of Monolithic Microwave Integrated Circuit (MMIC) technology, most of the components use Microstrip structure. In order to connect the active components to the ground in the Microstrip design is limited by the thickness of the substrate to avoid circuit performance degradation due to vertical coupling. Thus it can be said that the Microstrip is not the primary choice of design in operating components at microwave and millimeter wave frequencies. The Coplanar Waveguide (CPW) design technique was proposed as an alternative to the Microstrip structure for MMIC components. With CPW design technique, it generates components and circuits which are cost-effective and allow miniaturization of components in MMIC environment. In this paper, CPW Low Pass Filter (LPF) electromagnetic modeling has been demonstrated based on multilayer MMIC technology for the 2,100 MHz mobile application. The LPF CPW specification has been modeled with the substrate of GaAS (εr=12.9) and Polymide (ϵr=3.7). The thickness of GaAS substrate and Polyimide dielectric is 600 micron and 2.5 micron respectively for each layer.