Fast analysis of electromagnetic scattering problems using SAIM-FAFFA method

A subdomain adaptive integral method (SAIM) in conjunction with the fast far-field approximation (FAFFA) technique is presented for fast analysis of electromagnetic scattering from 3D PEC objects. In the SAIM technique, the whole structure is divided into several subdomains and each subdomain is properly enclosed in its local Cartesian grid. Then the AIM is applied to reduce the matrix storage and accelerate the matrix-vector multiplication for each subdomain. A current continuity boundary condition between adjacent subdomains is introduced to ensure the accuracy. Moreover, the FAFFA technique is adopted to speed up the process of updating the modified excitation vectors. Numerical results show that good accuracy of the proposed SAIM-FAFFA is achieved.