A Hierarchical Fast Solver for EFIE-MoM Analysis of Multiscale Structures at Very Low Frequencies

We present an EFIE fast solver that is stable down to very low frequencies, for very dense meshes and multi-scale problems. The proposed approach uses a split-potentials formulation in association to a hierarchic pre-conditioner for the underlying low-rank fast factorization. Potential splitting prevents the numerical cancellation problem that undermines the effectiveness of the low-rank factorization, negatively impacting on the necessary factorization tolerance. The fast method presented in this work can be directly implemented into existing codes.