Volume-integral-equation-based analysis of transient electromagnetic scattering from three-dimensional inhomogeneous dielectric objects

A novel technique for analyzing transient electromagnetic scattering from t hree-dimensional inhomogeneous dielectric targets is proposed. An integral equation for the electric flux density throughout the scatterer is construc ted by invoking the electromagnetic volume equivalence principle. This equa tion is solved using a marching-on-in-time scheme in which the electric flu x density is expanded in space by volumetric rooftop basis functions define d on a tetrahedral mesh and in time by piecewise polynomials. The proposed method is validated for representative dielectric structures by comparison via Fourier transformation of scattering data obtained with this method and various frequency domain techniques.