Ionospheric Decontamination Based on General Parameterized Time-frequency Analysis for High-frequency Hybrid Sky-surface Wave Radar

In high-frequency (HF) hybrid sky-surface wave radar, the first-order sea clutter broadening is very severely under the influence of ionosphere, which affects the detection of ship target. A cascaded method is described to correct HF signals reflected by the ionosphere and backscattered by the sea surface for ionospheric frequency modulation, which produces spectral line smearing. Firstly, the radar configuration, sea clutter broadening model are introduced based on the newly-developed integrated HF sky-surface wave experimental system. Then, a new ionospheric decontamination method based on General Parameterized Time-frequency (GPTF) analysis is proposed to correct the ionospheric phase contamination with large amplitude. Finally, the proposed method is examined by measured data. Experimental results indicate that the proposed method can well suppress the broadening sea clutter and improve the ship target detection performance.