Computationally efficient subspace-based method for direction estimation and tracking in array processing

In this paper, we propose a new computationally efficient subspace-based method without eigendecomposition (SUMWE) for the direction-of-arrival (DOA) estimation of narrowband signals impinging on a uniform linear array (ULA) by exploiting the array geometry and its shift invariance property. Further an adaptive implementation of the SUMWE is presented for tracking the time-varying directions of slowly moving (relative to the sampling rate) signals. The effectiveness of the proposed algorithm is verified through numerical examples, and it is shown that the proposed algorithm is computationally simple and has a good tracking performance.