Broadband beamforming on the 2-D transform plane

On taking the 2D Fourier transform of the output of a linear array, a ridge will appear on the frequency-wave number plane if a source is present. The slope of this ridge is determined by the direction of arrival of the wavefront. Two methods are proposed to estimate this slope. The first one takes the sums of the squared magnitude of the transform along predetermined slopes to find the maximum sum. The second one requires less computation; it first locates all the maxima of the transform. A weighted-least-squares fit is then taken through these maxima to give a slope estimation. The multisource case is considered, and properties and statistics of the beamformer, together with simulation results, are given