Hybrid clutter-map/L-CFAR procedure for clutter rejection in nonhomogeneous environment

The author introduces a new CFAR procedure, which relies on a hybrid clutter-map/L-CFAR strategy, aimed at improving the system robustness against possible nonhomogeneities, while preserving target detectability in a homogeneous environment. After presenting the procedure, guidelines for the design of the relevant system subblocks are given, from both quantitative and qualitative points of view. As to the performance analysis, closed-form formulas are given for the detection and false alarm probabilities in case of a single point-like target, showing that proper system design yields near-optimum performance. Moreover, approximated expressions of the detection probability are derived for the case of multiple targets entering the map cell, and possibly persisting in there for several scans: it is shown that data censoring prevents the masking effect which is typical of clutter-map systems, at the price of a very limited incremental CFAR loss