Surface impedance for coated bodies of revolution: a finite difference approach

A hybrid method is developed to obtain an approximate surface impedance for homogeneous or perfectly conducting bodies of revolution (BORs) coated with thin dielectric layers. It concerns bodies of various shapes whose dimensions are small or comparable to the wavelength lambda , for which accurate results and reasonable computation times are expected. A numerical evaluation of a perfectly conducting convex BOR with a single homogeneous layer with plane wave excitation is presented. It is shown that this method provides an accurate approximation to the true impedance on the outer surface of the coating. Furthermore, the speed of computation in a few hundred times faster than that of the method of moments.<>