Spatial weighting in signal subspace direction-of-arrival estimation

A novel approach for spatial weighting in high-resolution signal subspace methods for direction-of-arrival (DOA) estimation is proposed. It is based on a duality relation obtained when the weighting matrix has a band-Toeplitz structure and is applied to the array signal correlation matrix rather than directly to the array output. The result is a much larger freedom in choosing the array response than in the output-weighted beamspace approach since the weighting need no longer be restricted to that of a conventional beamformer but can be of a general polynomial type. The proposed scheme also preserves all structure of the original signal subspace estimation problem. Simulations are provided to illustrate the advantages with the scheme