The radar frequency backscattering behavior of rough ocean surfaces has been investigated using a physical scale modeling approach and a millimeter-wave compact radar range. The method involved fabrication of two 1/16th scale simplified rough ocean surfaces from a material that at 160 GHz behaved as the dielectric equivalent of seawater at 10 GHz. By measuring the backscattering behavior of the physical models in a 160 GHz compact range, the X-band radar frequency scattering behavior was determined. Though the physical models used were static, a scale modeling approach readily offers the ability to examine ocean backscattering phenomenology of a given surface texture over an extended range of look angles and radar frequencies, which otherwise would be challenging in a dynamic ocean environment. Computational electromagnetic modeling of the surface was also performed and compared with compact range measurements. This effort, involving more realistic ocean surfaces, builds on previous ocean modeling work presented by our team that utilized a periodic rough surface. The simulated surfaces studied here represent a natural progression toward our goal of developing reliable methodologies to characterize the backscattering behavior of land and sea clutter using physical scale modeling technologies.
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