GLRT-based array receivers to detect a known signal corrupted by noncircular interferences

The problem of detecting a known signal with unknown parameters in the presence of interferences, whose second order statistics (SOS) are unknown, has received considerable attention these last decades. However, most of the available receivers assume second order (SO) circular interferences and become suboptimal in the presence of SO noncircular interferences, omnipresent in applications such as radar, satellite localization or radio communications. The scarce optimal receivers taking into account the potential SO non-circularity of the interferences have been developed under the limiting assumption of a known signal with known parameters or of a random signal. For this reason, following a generalized likelihood ratio test (GLRT) approach, we introduce different new array receivers for the detection of a known signal, with different sets of unknown parameters, corrupted by unknown noncircular interferences and we analyze their performances. Specifically, we show that these new non conventional (NC) detectors entail large gains in performance with respect to conventional (C) ones, depending on the a priori information available.