Multilevel Fast Multipole Algorithm Enhanced Characteristic Mode Solver for Large-Scale Objects

Typically, the characteristic mode (CM) analysis is based on the electric field integral equation (EFIE) and the characteristic modes are calculated numerically using the method of moments (MoM). The high computational complexity of conventional MoM approach hinders large-scale CM analysis in the practical engineering application. In this paper, the conventional multilevel fast multipole algorithm (MLFMA) is embedded into the implicitly restarted Arnoldi method (IRAM), an iterative eigenvalue solver to solve standard complex eigenvalue problem, which provides an appealing possibility for the CM analysis of electrically large complex objects.