A focused image processing procedure using near zone scattered fields obtained in a compact range

The backscattered data are obtained using an array of defocused feeds which simulate a complex illumination of the target. The target is kept stationary, and its backscattered field is received by each array element. The focusing procedure is applied by appropriately compensating the phase of the backscattered field received by each element. These compensated signals are summed coherently to obtain a cross-range/down-range image of the target which indicates the location of the various scattering centers associated with the target. Numerical examples and experimental results are presented to validate this technique