Fast analysis of EM scattering by joint use of the MLFMA and the FGG-FG-FFT

In this paper, a hybrid algorithm of the MLFMA and the FGG-FG-FFT is proposed for fast analysis of multiscale EM scattering from electrically large PEC objects. For multiscale problems, both the MLFMA and the FGG-FG-FFT have their own disadvantages. However, the hybrid algorithm can more easily deal with multiscale problems, leading to higher efficiency than either of these two algorithms. Numerical examples are provided to demonstrate the validity and efficiency of the proposed method.