Finite element analysis of cable shields to investigate the behavior of the transfer impedance with respect to fast transients

Investigation of electrical fast transients and their influence on signal integrity in shielded cables is an important topic in the field of electromagnetic compatibility (EMC). Signal integrity problems can occur on the basis of coupled disturbances on the transmitting cable in form of fast transients caused by some electromagnetic interference (EMI) current in the shield together with the transfer impedance. The aim of this paper is to develop an applicable model to calculate and estimate the behavior of cable shields and their transfer impedance over a wide frequency spectrum and under the direct influence of fast transient phenomena.

I. Introduction

Currently, the influence of transient events on cable shields and their influence on the quality of signal transmission still is not fully clarified. Manufacturers provide graphical data regarding shielding effectiveness but insufficient information concerning the transfer impedance which is known to be an important parameter.