Computationally efficient method for joint azimuth-elevation direction estimation with L-shaped array

For overcoming the problems of pairing failure and estimation failure, which are frequently encountered in two-dimensional (2-D) direction-of-arrival (DOA) estimation of multiple signals, we propose a new computationally efficient subspace-based based 2-D DOA estimation with automatic pair-matching method for noncoherent narrowband signals impinging on the L-shaped sensor array structured by two uniform linear arrays (ULAs). In the proposed method the computationally expensive procedures of eigendecomposition in subspace estimation and pair-matching of the estimated azimuth and elevation angles are avoided, while the problems of pairing failure and estimation failure are overcome. The statistical analysis is studied, and the closed-form expressions of the asymptotic mean-square-errors (MSEs) of the elevation and azimuth estimates are derived explicitly. Finally the effectiveness of the proposed method and the theoretical analysis are substantiated through numerical examples.