New electrical equivalent circuit model of the inset fed rectangular patch antenna

Abstract

We present through the study of the discontinuity between transmission line and conductor backed coplanar wave guide a new accurate equivalent circuit model for the inset fed rectangular patch antenna. In this work the inset fed rectangular patch antenna is decomposed into three parts: transmission line part which is the feed line. The second part is the conductor backed coplanar waveguide witch is at the middle of the antenna structure, and the last one, is again, a transmission line one. Each of these parts will be studied a part: each of them is characterized by its characteristic impedance Z c and its electrical length s computed via LineCalc tool of Advanced design system software than all parts will be put together to form our antenna, but we have to study the discontinuities impact. In order to provide a perfect electrical model of the antenna at the resonance frequency the parameters for each discontinuity are computed using the reflection parameter: Su and transmission parameter: S12 related to the brought backed impedance for each part of the antenna. the validation of this work is done by the Momentum solver of Advanced Design System environment software, by taking into account the studied discontinuities and simulating the electrical circuit model on the same software so the comparison between Su given by the circuit model simulation and the one given by the electromagnetic Momentum simulation show a great accordance around the resonance frequency. Such electrical circuit model is very useful in front end simulation and it show the importance of the discontinuities which are neglected for most electrical model.