Space–time matrix method for 2-D direction-of-arrival estimation

This paper presents a novel space–time matrix method for two-dimensional direction-of-arrival estimation of multiple narrow-band sources impinging on the far field of a planar array. Using the proposed method, both the elevation angle and the azimuth angle of a source can be estimated by the same eigenvector of a space–time matrix, or the elevation angle is estimated by the eigenvector, but the azimuth angle is estimated by the corresponding eigenvalue. At the same time, the paring of the estimated elevation angles and azimuth angles is automatically determined. Compared with the previous works, the proposed method can provide better performance with substantially reduced computational complexity since the associated eigenvalue decompositions are for smaller-sized data matrices. In addition, it can resolve the incoming rays with very close azimuth angles or very close elevation angles.