Electromagnetic Susceptibility of a Folded Cable of Finite Thickness in a Shielded Enclosure To External Excitation

Abstract

A numerically efficient Fourier series approach to the analysis of a folded cable of finite thickness enclosed in a rectangular cavity is presented. The electromagnetic susceptibility of the cable to external excitation is considered by computing the electromagnetic fields that exist within the cavity enclosure, and the current response induced on the cable. The cable penetrating through the top face of the cavity is folded at right angle within it. This boundary-value problem is an idealization of a folded cable in some shielded enclosure. The formulation is based on the Fourier series approach developed by the author. The current response on the cable is approximated by a truncated Fourier series. The current on the cable, in turn, results in an electromagnetic field within the cavity which is associated with a triply infinite sum. By using the Fourier series technique, the unknown mode amplitudes and hence the unknown Fourier coefficients are evaluated. Other information pertaining to cable-shielded enclosure problems can easily be derived from the current and the field distribution. Numerical results are presented to illustrate the effects of cable diameters on the current response of the folded cable. A threshold value of the wire diameter is identified below which the cable behaves like a thin one.