摘要

An alternative multiresolution (MR) basis is presented for the method-of-moments (MoM) solution of the electric-field integral equation (EFIE) for the analysis of low-frequency problems. The proposed MR basis functions can be treated as an extension of the traditional loop-tree basis function to hierarchical functions. Similar to the loop-tree basis, the MR basis functions are linear combinations of standard Rao-Wilton-Glisson (RWG) functions. Therefore, the MR algorithm can be easily applied to MoM codes with RWG basis. Since the MR basis is immune from the so-called low-frequency breakdown, the MR basis is especially suitable for the analysis of low-frequency problems. Compared with the previous MR basis, the present MR basis is easier to construct and comprehend, and the basis-changing matrix is sparser. Physical interpretation and comparison are given for the previous and present MR bases. Numerical results demonstrate that the both the previous and present MR bases are efficient for 3D electromagnetic scattering problems at low frequencies.