Application of Asymptotic Waveform Evaluation to Hybrid FE-BI-MLFMA for Fast RCS Computation Over a Frequency Band

The asymptotic waveform evaluation (AWE) technique has been widely used in the method of moment (MoM), the finite element method (FEM), and the hybrid finite element-boundary integral method (FE-BI) for fast computation over a wide frequency band. However, how to apply AWE to the multilevel fast multipole algorithm (MLFMA) still remains challenge. This paper proposes an efficient and robust approach to apply AWE to the hybrid finite element-boundary integral-multilevel fast multipole algorithm (FE-BI-MLFMA). The validity of the proposed approach is verified by numerical examples for scattering problems. Numerical experiments show that the application of AWE to FE-BI-MLFMA can greatly improve the efficiency of FE-BI-MLFMA for computation of scattering over a wide frequency band.