An Analytical Method for Radiated Electromagnetic and Shielding Effectiveness of Braided Coaxial Cable

Abstract

Electromagnetic radiation from transmission lines is an important topic in electromagnetic compatibility. Thus, this paper aims at developing an analytical technique to evaluate radiated electric field and shielding effectiveness (SE) of shielded cable. The induced voltages and currents on the screen are modeled by the surface transfer impedance with Kley's method. Then, based on the Hertzian dipole technique, the radiating transmission line is decomposed into small-length hypothetical dipoles and the total electromagnetic radiation can be replaced by the summation of the dipoles. After that, the SE expression of shielded cable is obtained according to the electromagnetic calculation results, which is defined by using transfer impedance. Finally, numerical simulations are carried out by using a commercial software computer simulation technology (CST) to validate the proposed approach. The expressions give a way of allowing fast parametric analysis of radiation and SE during the design phase of the electrical and geometrical configuration of shielded cable.