The method of equivalent dipole moments (MEDM) combined with CBFM for the fast and accurate solution of dielectric scattering problems

High-resolution basis functions are employed for accurate modelling of electromagnetic scattering from dielectric objects. It is shown that the field radiated by each of these micro basis functions resembles the dipole field, even in the immediate vicinity of its cubic support. This, in turn, significantly eases the computational burden of generating the off-diagonal elements of the moment matrix. Furthermore, the on-diagonal self-term is known analytically and only governed by the electrostatic field (electrodynamic part is negligible). This method has been hybridised with the Characteristic Basis Function Method (CBFM) and the Adaptive Cross Approximation (ACA) algorithm to reduce both the size and generation time of the moment matrix equation. It is demonstrated that the proposed method, herein referred to as MEDM, is not only fast and memory efficient but it also generates an accurate solution of scattering problems associated with complex-shaped, thin and electrically large objects.