Modelling microwave emission from forests: theory and results

Models of microwave emission have generally represented vegetation as an ensemble of identical lossy scatterers characterized by global parameters, such as single-scattering albedo ω and optical thickness τ. Representation of leaves through dielectric discs, and of trunks, branches and stems by means of cylinders to model contributions to emission has been much less frequent than in the backscatter simulation case, although it turns out to be indispensable to explain several experimental observations. The model developed at Tor Vergata University, based on radiative transfer theory and the matrix doubling method, simulates emission of both agricultural and forest canopies through the bistatic scattering functions taking also into account the geometrical properties of the single vegetation elements