Performance evaluation of RQ non‐parametric CFAR detector in multiple target and non‐uniform clutter

The performance analysis of the rank quantisation (RQ) non‐parametric constant false alarm rate (CFAR) detector in homogeneous and non‐homogeneous backgrounds is carried out. A closed‐form expression of the false alarm rate of the RQ detector at clutter edges is derived. It is shown that the RQ detector pays an additional loss of about 3 dB in detection performance relative to the cell averaging (CA)‐CFAR with incoherent integration in homogeneous background, but it can accommodate a number of strong interfering targets within the reference window. When both of the heavy and the weak clutters follow a Rayleigh distribution, the rise of false alarm rate for the RQ detector at clutter edges lies between that of the CA‐CFAR and the ordered statistic (OS)‐CFAR with incoherent integration. If the Weibull distributed clutter with a long tail moves into the reference window, the rise of the false alarm rate of the CA‐CFAR, the OS‐CFAR and the greatest‐of‐CFAR with incoherent integration reaches a peak of more than three orders of magnitude, and cannot return to the original design P fa . However, the RQ detector reveals its inherent virtue that it can maintain a CFAR despite the changes in the underlying distributions of observed data.