Null-steering beamspace transformation design for robust data reduction

In this paper, we present a robust solution for data reduction in array processing. The purpose is to reduce the computation and improve the performance of applied signal processing algorithms by mapping the data into a lower-dimension beamspace through a transformation. Nulls steering to interference are incorporated into a transformation using the subspace projection technique, and the beamspace spatial spectrum estimation accuracy is evaluated and maximized with a measure. The derived transformation tries to preserve the full dimension Cramer-Rao bounds for the parameters of interest while rejecting undesired signals effectively. When compared with an optimal method and an adaptive approach, simulation results show that significant improvements are obtained in terms of beamspace direction-of-arrival estimation root-mean-squared error, bias and resolution probability.