Fast solver for uncertainty EM scattering problems by the perturbed-based MLFMA

A novel fast algorithm is proposed to analyze the EM scattering from electrically large conducting targets with varying geometrical shapes. Firstly, the target surface can be constructed with several control points by using the non-uniform rational B-spline surface modeling method. More specifically, the surface integral equation can be rewritten in terms of these control points, which contains the geometrical coordinate information. Moreover, it should be noted that the derivatives of both the L and K operates are needed to describe the perturbation of electric currents. Therefore, a perturbed multilevel fast multipole algorithm (P-MLFMA) is proposed to accelerate the matrix vector multiplication. At last, numerical results are given to verify the accuracy and efficiency of the proposed P-MLFMA. It can be seen that higher computational efficiency can be obtained when compared with both the traditional Monte Carlo method and the Perturbation Approach for MoM.