Efficient Calculation of Electromagnetic Scattering Problem with Multiple Excitations by Sherman-Morrison-Woodbury Formula

In this article, the Sherman-Morrison-Woodbury (SMW) formula is applied to accelerate the direct solution of electromagnetic scattering problem with multiple excitations by electric field integral equation (EFIE). To reduce the calculation burden in method of moments (MoM), the dense discretized impedance matrix is transformed into several diagonal matrix blocks via the SMW formula. The low rank matrices are compressed by Lagrange interpolations. The adaptive cross approximation algorithm (ACA) is applied to reduce the storage costs for multiple right-hand sides (RHS) matrix, which can solve the monostatic radar cross section (RCS) over a wide angular band efficiently. The numerical results demonstrate both the effectiveness and accuracy of the proposed method.