An Equivalent Circuit Model for Predicting EM Radiation from Stripline Structure with a Thin Wire

摘要

In recent years, effective methods for predicting and suppressing EMI over a broad band are required. In this paper, we newly focus on prediction of EM radiation from a strip line structure with a ground thin wire by an equivalent circuit model. Firstly, frequency responses of common-mode (CM) current on the PCB and EM radiation are studied with FDTD modeling. Secondly, an equivalent circuit model for predicting CM current was proposed. The equivalent circuit model for prediction is based on consideration of concepts of CM antenna impedance distributed constant circuit and electric coupling between the power plane and the thin ground wire. The good agreement between the predicted and full-wave results indicates the validity of the equivalent circuit model. The frequency response of EM radiation from strip line structure can be identified using our proposed model. In addition, the equivalent circuit model provides enough flexibility for different geometric parameters and can be used to develop physical insights and design guidelines.