A Compound Volume Scattering Model With Emphasis on the Morphological Diversity of Vegetation Canopy Scatterers

Existing volume scattering models play an important role in interpreting the scattering characteristics of vegetation canopies. A common assumption of these models is that a vegetation canopy consists of one type of particle. However, since a vegetation canopy comprises boughs, twigs, and leaves (or needles), they tend to form scatterers with various shapes, resulting in differing scattering processes. In this article, we propose a new volume scattering model. The proposed scattering model uses an isotropic plate, isotropic dihedral, and dipole particles to model vegetation scatterers. Different preferred orientation angles characterize the latter two types of particles. The proposed method is validated with AIRSAR and ALOS2/PALSAR2 datasets. The results show that the proposed model provides us an opportunity to extract refined scattering processes of vegetation canopies. In addition, it can be found that the proposed model shows potential in vegetation classification and biomass estimation, resulting from modeling a vegetation canopy as various types of particles.