A study of dense medium effect using a simple backscattering model

In an electrically dense medium, when the spacing between the scatterers is comparable to the wavelength, it is important to incorporate the near field effect, both amplitude and phase, into the backscattering theory. In this paper, a simple backscatter theory based on radiative transfer (RT) theory is presented. The random medium, bounded on top and bottom by a rough surface, contains a layer of randomly distributed spherical scatterers. The phase matrix for these closely packed discrete scatterers is obtained using the dense medium phase and amplitude correction theory (DM-PACT) and the rough surface is characterized by the IEM model. The integro-differential equations of radiative transfer theory are solved iteratively up to second order solutions. Scattering terms for direct surface, direct volume, surface-volume and volume-volume interactions are identified. These results are compared with full model solutions using the matrix doubling method.