DOA Estimation for Mixed Circular and Noncircular Coherently Distributed Sources Under Impulsive Noise

In this study, we propose a method for direction of arrival (DOA) estimation of mixed circular and noncircular coherently distributed (CD) sources under impulsive noise. The existing methods estimate the angular parameters of circular and noncircular CD sources simultaneously under Gaussian noise, but they encounter issues such as low resolution at small angular separation and performance degradation under impulsive noise. To overcome these challenges, we first construct an augmented norm covariance to mitigate the effects of impulsive noise, and then we present a high-resolution DOA estimation approach that handles circular, general noncircular, and rectilinear CD sources separately by analyzing the constraints satisfied by the generalized steering vector. We evaluate the superior performance of our proposed method through numerical simulations and compare it with the derived Cramér-Rao bound for the considered scenarios.