Maximum likelihood direction-finding in unknown noise environments

In array signal processing, most high resolution methods are established based on the spatially white noise model. However, in real environments, the noise model is often either unknown or undeterminable. This may cause the high resolution methods severe degradation in performance. In the paper, under the assumption that noise correlation is spatially limited, using two separated arrays, the authors propose a maximum likelihood method for the directions of arrival (DOA) estimation in unknown noise environments