Beamspace low complexity partially adaptive beamforming and angle of arrival estimations

Several applications such as RADAR, SONAR, underwater, space-satellite communication systems involve the use of very large arrays. In these cases the computational complexity related to array processing algorithms can become prohibitive for both adaptive interference cancellation and directions of arrival (DOA) estimation (or in general, parameters estimation). Herein we deal with the problem of reducing the degrees of freedom of the array processor for achieving a low complexity adaptive beamforming-DOA estimator system. We are mainly focussed into the problem of the interference cancellation. Hence the most part of the paper is devoted to outline a technique for a beamspace based partially adaptive beamformer (PAB) design. Then we show how effective beamspace-multirate DOA estimation algorithms can be implemented jointly to the proposed PAB.