Nondiagonally anisotropic PML : a generalized unsplit wide-angle absorber for the treatment of the near-grazing effect in FDTD meshes

Abstract

A new generalization of the PML with wide-angle absorption is presented, for the efficient truncation of FDTD lattices. The proposed unsplit-field layer uses a nondiagonal symmetric tensor anisotropy and via an appropriate parameter selection achieves notable attenuation rates in the case of near-grazing angles. Hence, it can be placed much closer to large structures. Improved accuracy and lower dispersion errors are attained via higher-order FDTD schemes with regular and non-Cartesian lattices constructed by hexagonal or tetradecahedral cells. Finally, Ramahi ABC's are invoked for the absorber's termination. Numerical results, addressing wave attenuation at grazing incidence, prove the efficiency of the proposed PML

Nondiagonally anisotropic PML: A generalized unsplit wide-angle absorber for the treatment of the near-grazing effect in FDTD meshes (PDF Download Available). Available from: http://www.researchgate.net/publication/3101799_Nondiagonally_anisotropic_PML_A_generalized_unsplit_wide-angle_absorber_for_the_treatment_of_the_near-grazing_effect_in_FDTD_meshes [accessed Jul 2, 2015].