Two-Dimensional DOA Estimation Algorithm for Coherent Sources Based on Axial Spatial Smoothing

This paper proposes a fast two-dimensional direction-of-arrival (2D DOA) estimation algorithm for coherent sources based on axial spatial smoothing of uniform circular arrays (UCA’s). The proposed algorithm begins with axial spatial smoothing of UCA, which is used to restore the rank of the covariance matrix to achieve the decoherence of coherent signals. Subsequently, beamspace transformation is applied to the denoised and smoothed covariance matrix. Finally, we can use UCA-ESPRIT algorithm to jointly estimate azimuth and elevation angles. Above all, we can quickly estimate 2 D DOA of coherent sources. This approach avoids computationally expensive spectral searches, significantly lowering complexity while ensuring automatic angle matching.