Solution of combined-field integral equation using multi-level fast multipole algorithm for scattering by homogeneous bodies

In this paper, we present an accurate method of moments (MoM) solution of the combined-field integral equation (CFIE) using the multi-level fast multipole algorithm (MLFMA) for scattering by large, three-dimensional, arbitrary-shaped, homogeneous objects. We first investigate several different MoM formulations of CFIE and propose a new formulation, which is both accurate and free of interior resonance. We then employ MLFMA to significantly reduce the memory requirement and computational complexity of the MoM solution. Numerical results are presented to demonstrate the accuracy and capability of the proposed method. The method can be extended in a straightforward manner to scatterers composed of different homogeneous dielectric and conducting objects.