Fast Analysis of Electromagnetic Scattering From Large-Scale Quasi-Periodic Arrays Using the CMBF-EIM-AEGA Method

An efficient modeling method for analyzing the electromagnetic scattering from large-scale quasi-periodic arrays with varying element sizes is proposed through a smart combination of characteristic mode basis functions (CMBFs), empirical interpolation method (EIM), and adaptive enriching greedy algorithm (AEGA). This method takes a small set of CMBFs as the entire-domain basis functions and extends it to the whole array in the process of the method of moments (MoM). To speed up the assembly time of the reduced MoM impedance matrix of the whole array resulting from CMBFs, the EIM is used for Green’s function interpolation to obtain a set of interpolation basis functions independent of geometric parameters. With this set of interpolation basis functions, the reduced MoM impedance matrix can be quickly assembled under any geometric parameters. The AEGA is employed to address the inefficiency of the EIM in high-dimensional parameter spaces induced by mutual coupling. As a result, the dimension of the final MoM matrix equation of modeling the whole array is significantly reduced and its solution process is greatly accelerated with shorter runtime. Finally, numerical results validate the efficiency and accuracy of the proposed method.