Doppler Bin Blanking CFAR Processor for Airborne Radars.

摘要

Constant false alarm rate (CFAR) processors are used to prevent automatic detection radar systems from becoming overloaded with false targets, in the presence of time varying or unknown interference environments. They maintain the number of false alarms at a level consistent with the design goals. Unfortunately, large clutter returns can cause severe degradation in the performance of these processors. The degradation manifests itself as a reduction in the ability to detect targets of a given signal to noise ratio, while maintaining the overall system false alarm rate. As well, the constant multiplying factor used in CFAR processors tends to vary as the range-Doppler resolution cell map changes. In this report a novel adaptive algorithm to exclude the range-Doppler cells which contain clutter is developed. This algorithm, when used in conjunction with a CFAR processor, greatly enhances the system's sensitivity to targets which reside in the clutter free region of the range-Doppler map. It is also shown that the CFAR multiplier is relatively invariant to changes in the geometric conditions of the radar, when the adaptive Doppler bin blanking scheme is used. This blanking scheme could lead to a simple CFAR processor which would be effective in any possible clutter environment.