Temporal impulsive noise excision in the range-Doppler map of HF radar

In this paper we present an effective scheme to excise impulsive noise pixels from a range-Doppler image or map. The temporal impulses in high frequency ocean surveillance radar (HFOSR) Doppler spectrum image arise due to local lightning discharges or man-made sources. Previous work focused on locating the noise position (detection) and applying a simple blanking technique, thereby burying targets in the noise spectrum. Built on these prior approaches, our current work develops an additional key step that uses weighted or block prediction method to estimate the possible true values of the destroyed ones. A range-Doppler image with much higher signal to clutter and noise ratio (SCNR) results. Another direct advantage over the former scheme is the improved robustness. Experimental images verify both the effectiveness and advantage of our method.