An efficient PML absorbing medium in FDTD simulations of acoustic scattering in lossy media

The concept of the PML is used to construct a novel, anisotropic, absorber for acoustic scattering FDTD simulations in lossy media. Overcoming the original PML lossless profile, it is proved that by a proper selection of additional attenuation parameters in a stretched coordinate system a theoretically zero reflection can be achieved, independently of frequency and incident angle. Numerical results - addressing several open-region problems of acoustic propagation and scattering in ordinary media - verify the efficiency of the proposed algorithm, and the accuracy of the computations.