A DOPPLER BIN BLANKING CFAR PROCESSOR FOR AIRBORNE RADARS

In this report a novel scheme for adaptively "blanking-out " the radar resolution cells which contain high clutter interference is developed and investigated. For the particular set of radar parameters that are used, a 60 dB clutter peak appears across all of the range gates, and many of the Doppler bins. If not dealt with, this huge peak severely degrades the performance of the CFAR processor, and reduces the sensitivity of the system to targets which reside outside of the clutter region. Our technique consists of adaptively excluding from the decision process, the range-Doppler cells located within this clutter peak region. As a result, the performance in the noise dominated interference region is greatly enhanced. Blanking out the clutter peak also reduces the variation which occurs in the values of the CFAR threshold multiplier over various geometric conditions in which the radar may be operated. It is shown that a single value of the CFAR constant can maintain the false alarm rate for large differences in the operating environment of the radar, if Doppler bin blanking is employed. Consequently, a much simpler CFAR processor can be implemented. RltSUM