Influence of canopy shape on SAR speckle distributions over woodland

A first order, mean field model for scattering from a woodland canopy is developed in the distorted Born approximation. The model is applied to simulated mixed woodland. Full account is taken of shading, shadowing and the SAR imaging process. The resulting simulated SAR images are barely distinguishable from real C-band SAR images of woodland, and show intensity speckle distributions that are well modelled by the K distribution at low to moderate resolutions. Speckle distribution shape is revealed to depend upon resolution, incidence angle, canopy topography and instrument function and the physical origins of these dependencies are identified within the context of the model