Collective scattering effects in vegetation canopies at microwave frequencies based on Monte Carlo simulations

Vector radiative transfer theory based on independent scattering can be invalid for certain cases of vegetation canopy where the scatterers can scatter collectively. Collective scattering effects include correlated scattering and the mutual coherent wave interactions between scatterers in close proximity of each other. The authors perform Monte Carlo simulations of scattering by vegetation with clustering structures. Two cases are considered. The first case is scattering from a large number of trees with clustering branches and leaves. The location and orientation of each branch and leaf is generated by using the stochastic Lindenmayer system (L-system) which is a technique of computer growth of vegetation and plants. The second case is vertical dielectric cylinders placed randomly on a dielectric surface. Results of both cases are compared with independent scattering