Adaptive beamforming for spatially spread sources

We consider the problem of adaptive beamforming for enhancing spatially spread sources. Traditional adaptive beamforming techniques have been designed for point sources which travel along a single path to an antenna array. However, in practical applications such as wireless communications, multipath propagation due to local scattering of the sources causes spreading of the signal energy around the nominal direction-of-arrival (DOA). We propose a non-parametric technique for estimating the spatial distribution, which is then used to design beamformer weights. Simulation examples demonstrate that the proposed technique performs well for a variety of multi-user scenarios using different spreading models.