Efficient Analysis of Electromagnetic Scattering in Large-Scale Finite Periodic Structures Using Characteristic Modes

Periodic characteristic mode (CM) analysis (PCMA) has proven to be an efficient method for analyzing large-scale finite periodic structures (LFPSs). However, its CMs are obtained solely from the reference cell, the solution process neglects the coupling effects among cells. To address this issue, this letter proposes an accurate method for analyzing the scattering properties of LFPSs. On one hand, by introducing dummy cells, the computation of CMs incorporates the coupling effects of surrounding cells, thereby improving accuracy. On the other hand, the compressive sensing (CS) technique is utilized to partially fill the impedance matrix to rapidly construct an overdetermined equation instead of a reduced matrix equation. Numerical examples are given to verify the accuracy and efficiency of the proposed method.