The improved constant false alarm rate detector based on multi-frame integration for fluctuating target detection in heavy-tailed clutter

In this paper, attention is devoted to the analysis of the detection threshold based on the multi-frame integration in heavy-tailed clutter for the radar with high resolution and even smaller grazing angle. The closed-form expressions of both the probability of the detection and the probability of false alarm for the heavy-tailed clutter background, which can be used for the theoretical analysis of constant false alarm rate (CFAR) detectors, are derived with the multi-frame integration technique. Accordingly, an improved CFAR detector is designed to work well with the presence of target-like outliers in the heavy-tailed clutter. In addition, the proposed CFAR detector is capable to alleviate the masking-effect resorting to the additive feedback operation when a target is large enough to cross several cells in multi-target case. The theoretical analysis and numerical simulations demonstrate that the proposed CFAR detector based on multi-frame integration can improve the signal-to-clutter rate of the targets exhibiting better performance than ones based on single frame in heavy-tailed clutter background. It is validated from the simulations that the proposed CFAR detector with additive feedback operation can deal with masking-effect for large target occupying several cells.