An equivalent dipole-moment method combined with multilevel adaptive cross approximation for PEC targets

A novel hybrid method is proposed for solving electromagnetic scattering problem of three-dimensional perfect electric conducting (PEC) targets with electrically large size. In this work, we use the equivalent dipole-moment method (EDM) to accelerate the near region interactions in the multilevel adaptive cross approximation (MLACA) via solving the surface integral equation (SIE). Compared with the conventional MLACA, the time of near region interactions can be much reduced using Rao-Wilton-Glisson (RWG) basis functions. On the other hand, the proposed method can save memory requirement of the EDM from O(N²) to O(N^4/3 log N), where N is the number of unknowns. Numerical results are presented to validate the efficiency and accuracy of this method.