Improved adaptive-beamforming target for self-calibrating a distorted phased array

An improved adaptive beamforming procedure is presented for self-calibrating a distorted phased array. The multiple scatterer algorithm (MSA) combines the echoes from several range bins to synthesize a beamformer that is less perturbed by clutter than the basic dominant scatterer algorithm (DSA). It was tested using experimental microwave echoes from industrial sites near Phoenixville, PA. It was found that the MSA can synthesize a nearly ideal beamformer using the echoes from three range bins having good beamformers, and that it can improve the image quality using the echoes from three bad beamformers, each of which is incapable of phase cohering the array by itself. >