An algebraic preconditioner based on properties of the skew-hermitian part of the linear systems arising from the discretization of the e-field integral equation

It is well established in literature that the rate of convergence of the Generalized Minimum Residual Method (GMRES), when it is applied to the solution of the (generally dense and unstructured) linear systems of equations coming out from the discretization process of the Electrical Field Integral Equation (EFIE) through the Method of Moments (MoM), can be significantly improved by a suitable preconditioning strategy. Along those lines the present paper inquiries the advantages of employing an easy-to-build algebraic preconditioner based on some expected properties of the skew-Hermitian part S of the MoM impedance matrix Z. Some numerical results are presented in order to evaluate its performances and numerically validate the proposed approach.