Study on Circularly Polarized Sea Clutter Doppler Spectrum Based on Refined Facet Scattering Field Model

As the primary source of interference in radar echoes, the Doppler spectrum of sea clutter directly reflects the motion state and scattering characteristics of the sea surface and serves as the core basis for clutter suppression and the inversion of sea state parameters. Given the unique advantages of circularly polarized sea clutter, such as strong polarization isolation and sensitivity to asymmetric scatterers, the circularly polarized electromagnetic scattering field of two-dimensional linear time-varying sea surface was modeled based on a refined facet scattering field model. Based on this, the simulation of the circularly polarized sea clutter Doppler spectrum at L-band was achieved. By utilizing the characteristic parameters such as the peak frequency, 3dB bandwidth, inter-peak spacing and peak ratio, the influences of polarization, incident angle, wind speed and wind direction on the characteristics of the circularly polarized sea clutter Doppler spectrum were systematically analyzed. The research results have certain reference significance for radar clutter suppression in complex sea conditions and sea surface parameter inversion.