The effective scatterer approximation in mean field modeling of random media with application to vegetation canopies

The mean electromagnetic field problem of partially organized random media has been studied in relation to organized vegetation canopies such as agricultural crops. The row structure in these canopies may induce coherence related effects such as the enhancement of backscattered power in excess of the classical backscattering enhancement and may also lead to enhancement or de-enhancement of thermal emission in passive remote sensing.;These existence of these enhancement effects is shown by Monte-Carlo simulations. Monte-Carlo simulations are performed to simulate the propagation, backscattering and emission by a defoliated corn canopy. The canopy is assumed to be composed of dielectric cylinders that are distributed with an average periodicity.;For the mean field problem of organized canopies an analytic method is developed. For this purpose, the more general problem of an ensemble of partially organized particles is considered where the particles are distributed in bounded disjoint regions. In this analytic method a fictitious effective scatterer is first defined. With suitable approximations the mean field problem is cast into an equivalent deterministic problem of a collection of effective scatterers. Numerical results are compared with Monte-Carlo simulations.