Robust adaptive beamforming via recursive spatial autoregressive modeling

In this work, we propose a new diagonal loading approach to improve the robustness of the standard Capon beamformer. For this purpose, the array is analyzed using spatial autoregressive modeling. The proposed regularization method is order-recursive, which allows the definition of a Levinson-like algorithm. This eliminates the need to invert the regularized array covariance matrix, essential for all types of Capon beamformers. The proposed diagonal-loading approach involves two regularization parameters, thereby increasing the robustness compared to one-parameter diagonal-loading approaches.