This paper presents a novel method of sea state characterization by using four criteria, which are applied to normalized experimental Synthetic Aperture Radar (SAR) one–dimensional signatures (range profiles), provided to our research group by SET 215 Working Group on “SAR radar techniques”. These criteria are the “Fractal Dimension”, “Fractal Length”, “Variance σ²”, and “Power Spectrum Density - Least Squares”. The “Fractal Dimension” and “Fractal Length” criteria, which appear to be the most important out of the four criteria, use the “blanket” technique to provide sea state characterization from SAR radar range profiles. It is based on the calculation of the area of a “blanket”, corresponding to the range profile under examination, and then on the calculation of the corresponding “Fractal Dimension” and “Fractal Length” of the range profile. The main idea concerning this proposed technique is the fact that normalized SAR radar range profiles, corresponding to different sea states, produce different values of “Fractal Dimension” and “Fractal Length” for all angles of incidence examined here. As a result, a sea state characterization technique for two different sea states (turbulent and calm sea) is presented in this paper.

In this paper, we introduce a novel method for calculating the electromagnetic (EM) field below a flat interface between two lossless media when a radiating vertical Hertzian dipole (VHD) is located far from the interface. The method uses a Geometrical Optics (GOs) approach based on the concept of ‘equal optical lengths’, in the framework of which the location of the ‘virtual image’ of the original source is calculated. Using the well-known formulae for the far EM field of a vertical Hertzian dipole, the EM field at a point below the flat interface is calculated in a closed mathematical form.