An equivalent dipole-moment method combined with multilevel fast multipole algorithm for PEC targets

In this paper, an equivalent dipole-moment method (EDM) combined with multilevel fast multipole algorithm (MLFMA) is proposed for the electromagnetic scattering from three-dimensional (3D) perfect electric conducting (PEC) targets. In this work, we use the MLFMA to accelerate the interactions in the far regions, and the EDM in the near regions via solving the surface integral equation (SIE). Compared with the conventional EDM, the memory requirement and CPU cost are reduced from O(N²) to O(N log N), where N is the number of unknowns. On the other hand, the proposed method saves CPU time compared with the conventional MLFMA using Rao-Wilton-Glisson (RWG) basis functions. Numerical results are presented to validate the efficiency and accuracy of this method.