Derivation and Analysis of an Adaptive Detector with Enhanced Mismatched Signals Rejection Capabilities

We consider the problem of adaptive radar detection with a view to provide a detector with high sidelobe signals rejection capabilities. Towards this end, we consider a modification of the adaptive beamformer orthogonal rejection test by enforcing the presence of a fictitious signal under the null hypothesis, orthogonal to the presumed target signature in the whitened space. We derive the generalized likelihood ratio test for this problem and provide analytical expressions for its probability of false alarm and probability of detection, for both matched and mismatched signals. The new detector is shown to offer very good performance in terms of mismatched signals rejection.