Efficient computation of transient TM scattering from a cylinder above an infinite periodic surface

The transient electromagnetic field scattered by a perfectly conducting cyl inder located above an infinite, perfectly conducting, periodic surface is computed for TM polarization. A decomposition technique is used to form a s et of coupled electric field integral equations for the current on the cyli nder and that portion of the surface most strongly interacting with the cyl inder. Use of this technique for studying the transient multipath phenomeno n of a target located above a sinusoidal surface is discussed.