Small scale surface roughness effects on enhanced backscatter from a layer of vegetation

The effect of surface roughness on enhanced backscatter from a layer of vegetation is investigated. The vegetation layer is modeled as a discrete random media over a dielectric half-space and a rough surface having a Gaussian height profile. The following scattering components are present within the layer: direct (or volume) scatter, direct-reflected scatter and surface scatter. The direct-reflected scatter consists of two components that have equal path lengths at backscatter, resulting in enhanced backscatter for like-polarized radar returns. The reduction in this enhanced backscatter due to small-scale surface roughness is shown to be less pronounced for layers with low volume scatter and high direct-reflected scatter.