Experimental and theoretical comparison of some algorithms for beamforming in single receiver adaptive arrays

Adaptive null steering in single receiver adaptive arrays is discussed. Since the single receiver structure allows only output power for a given set of weights to be measured, the problem is to adaptively adjust the weights of the antenna array, based on output power measurements only, so as to reject interference signals while maintaining a fixed response in a given look direction. The key idea of this work is to determine the optimal beamformer weights in a single step, by estimating the covariance matrix of the array sensor outputs using a weight perturbation technique. Based on this covariance matrix estimate, three different approaches for finding the beamformer weights are studied.