This paper studies adaptive radar detection of point-like targets in the presence of Gaussian interference and possible diffuse multipath. For this problem, [3] proposed a Tunable Adaptive Matched Filter (T-AMF) detector which contains a tuning parameter ruled by the strength of multipath effects. This paper develops a two-stage strategy for the selection of the tuning parameter by jointly using a two-step energy detector and the expected likelihood (EL)-based principle. Once plugged into the T-AMF, the selected parameter yields a fully adaptive detector free of any user parameter. Remarkably, the new architecture possesses the desired constant false alarm rate (CFAR) property with respect to the disturbance covariance. Finally, its detection performance is assessed and validated via numerical examples.

diffuse multipath; adaptive signal detection; tuning parameter; energy detector; expected likelihood approach