Ionospheric Decontamination Method Based on Optimization Criteria in Over-the-Horizon Radar

Abstract

Over-the-horizon (OTH) radar is important equipment for wide-area surveillance; it has several uses, including aircraft tracking, ship and missile detecting, and remote sensing of the ocean surface. OTH radar uses high frequency electromagnetic wave which propagates by means of refraction within ionosphere; it can provide large range coverage. But this will cause phase contamination due to the unstable movement of the ionosphere. The spectrum of sea clutter and target will be expanded by the ionospheric contamination in the Doppler domain, which will cause the ship target more difficult to separate from the clutter and even buried in the clutter. A new decontamination method is proposed to solve this problem. By analyzing the sea clutter signal model, the proposed method designs an ideal optimized matrix and then uses optimization criteria to estimate phase contamination. Based on the real data, the effectiveness of the new method was validated and compared against other methods.