Fast computation of RCS of 3D electrically large structure by modified multilevel fast multipole algorithm

In this paper, two novel strategies are proposed to determine the multipole number of multilevel fast multipole algorithm (MLFMA). With the modified multipole number, the computation of RCS of 3D electrically large structures is realized. Compared with traditional MLFMA, The proposed methods in this paper can reduce the multipole number, CPU time and the memory requirement. Numerical results show that the modified methods have the complexity of O(N log N) both for the computation of matrix-vector multiplication and the memory requirement, thus yields more efficiency for scattering problems of 3D electrically large structures.