An efficient approach to evaluate multiple scattering by foliage in a 3D-FDTD model

In this paper, an approach is presented to study multiple scattering by periodically arranged obstacles in the 3D finite-difference time-domain (FDTD) method. The computational efficiency is improved by applying period boundary conditions; in this way multiple passages through the zone with scattering objects can be modeled. This method is exemplified by modeling sound propagation through foliage. Leaves are modeled as bending plates with damped vibrations. The separation of the incident wave and reflected wave is realized in frequency domain by using the least squares method. The energy attenuation obtained by propagation through this scattering medium can be calculated based on the cross power spectral density of pressure and velocity in the propagation direction. Finally, the method has been used to quantify the effect of different foliage properties on sound propagation through them.