Dense medium radiative transfer theory: comparison with experiment and application to microwave remote sensing and polarimetry

The dense medium radiative transfer theory is used to study the multiple scattering of electromagnetic waves in a slab containing densely distributed spherical particles overlying a homogeneous half-space. This theory is used to explain phenomena observed in a controlled laboratory experiment. The experimental data indicate that, in a dense medium with small particles, both the coherent attenuation rate and bistatic intensities first increase with the volume fraction of the particles until a maximum is reached, and then decrease when the volume fraction further increases. Thus, attenuation rates and bistatic scattering exhibit a peak as a function of the concentration of particles. The magnitudes of both are also less than those predicted by the independent scattering assumption and the conventional radiative transfer theory. These phenomena cannot be explained by the conventional radiative transfer theory. It is shown that the dense medium radiative transfer theory is in agreement with these experimental features