Quasi‐Helmholtz projector including multibranch Rao‐Wilton‐Glisson basis functions for multiscale objects at low frequency

Abstract

AbstractIn this letter, a Quasi‐Helmholtz Projector method including multibranch Rao‐Wilton‐Glisson (MB‐RWG) basis function to calculate the scattering problem of multiscale targets at low frequencies is proposed. The loop basis function and the star basis function including MB‐RWG basis function are constructed, and the loop basis function and the star basis function including MB‐RWG basis function are used to construct the Quasi‐Helmholtz Projector. The proposed method is coined MB‐Quasi‐Helmholtz Projector (MB‐QHP) method. The MB‐QHP method can effectively solve the low frequency breakdown (LFB) problem in electric field integral equation (EFIE). Compared with the MB‐loop‐star method, the condition number is lower, the convergence is faster, and the search for global loop is avoided. Meanwhile, due to the existence of the MB‐RWG basis function, the proposed method can divide the calculation region into several regions with different mesh sizes. Numerical example shows the advantages of the proposed method.