Experimental analysis of a HF hybrid sky-surface wave radar

High-frequency (HF) radar systems exploit refractive and diffractive properties of HF waves to sense targets beyond the line of sight. HF skywave radars use the ionosphere medium to reflect the signals and thus illuminate targets of thousands of kilometers away, but they suffer from the close-distance blind zone and severe ionosphere decorrelation effect. HF surface wave radars exploit the diffraction of vertically polarized waves to detect targets within hundreds of kilometers offshore. But the diffracted surface wave is highly attenuated, and the radar has the vertical incidence ionospheric clutter problems. High-frequency hybrid sky-surface wave radar (HFSSWR) is a novel radar configuration containing a skywave transmitting path and a surface wave receiving path, which is a natural combination of HF skywave and HF surface wave radar systems [1]. In addition, multiple separate receiving sites can compose a multistatic network and operate with only one transmitter. The system configuration is flexible.