Extraction of ionospheric clutter in HFSWR

The two main applications of High frequency surface wave radar (HFSWR) are maritime surveillance of the Exclusive Economic Zone (EEZ) and the remote sensing of the sea. Ionospheric clutter strongly limits the detection capabilities of HFSWR. In order to analyze the effect of ionospheric clutter, a method based on image processing is proposed to extract ionospheric clutter. In this method, the Range-Doppler spectrum of radar echo was processed as image, and the color image segmentation technique was used to extract ionospheric clutter. By a preliminary analysis of the ionospheric clutter extract results, we can get that the average power of ionospheric clutter is big, and it occupies many Range-Doppler cells, and it has direction. The results provide a frame of reference for the ionospheric clutter assessment, suppression and frequency selectivity, etc.