Synthetic dense media fabrication with application to sea ice

Microwave remote sensing of sea ice has been an area of intensive study for over twenty years due to the role of sea ice in the global energy balance and due to its navigational importance. In theory, sea ice has usually been modelled as a collection of spherical scatterers within a dielectric medium. Using this approach, various researchers have tried to match measurement data with models that account for assumed important scattering mechanisms such as positional correlation between scatterers or close spacing effects. However, until now there have been few experiments in which the various scattering mechanisms, assumed to be of importance within the sea ice, have been studied precisely. This paper presents a fabrication technique for synthetic dense media, in which scatterer positions are robotically controlled. The authors also examine the measured effects of deviation from uniformity of scatterer distribution, particle clustering, and volume fraction dependence. These effects will be examined by comparing microwave scattering from various manually and robotically fabricated dense medium targets composed of a polystyrene background with glass spheres as scatterers