A Novel Time-Domain Asymptotic Solution for a Backward Transient Scattered Electric Field by a Coated Metal Cylinder

In this paper, we propose a novel high frequency method for a backward transient scattered electric field by a metal cylinder covered with a lossless dielectric medium layer (coated metal cylinder). A time-domain (TD) asymptotic solution, which is referred to as a TD Fourier transform method (TD-FTM), is derived by applying the FTM to a backward transient scattered electric field expressed by an integral form. The TD-FTM is represented by a combination of a direct geometric optical ray (DGO) and a reflected GO (RGO) series, where each field component is given by a closed form. The accuracy and practicality of the TD-FTM are evaluated by comparing it with three reference solutions.