Noise versus Coherency in Mm-wave and Mi- Crowave Scattering from Nonhomogeneous Materials

Forward scattering effects have been studied and compared when nonhomogeneous medium is illuminated by coherent and quasi-noise sources operating in mm-wave and microwave ranges. Double-layers dielectric structure simulating Fabry-Perot resonator properties was employed to develop a relevant model used for comparing transmittances of both coherent and noise signals. Experiments with nonhomogeneous materials such as coal, wood chips, sand and others have proved the basic modeling predictions and the role of noise bandwidth in averaging process important for material characterizations. It was found out that efficient averaging associated with noise nature of probing signal can be reached for the relative noise bandwidth of 25% and more.