Calculating the Poles of Complex Radar Targets

Abstract

The complex natural resonances (poles) of complex radar targets are usually extracted frommeasured signature, and have low precision because of being extremely sensitive to noise. In numerically methods to calculate targets' poles, the method of moment (MoM) combined with contour integration is a smart one and widely used. But that method is limited to simple shaped or revolution objects. For complex shaped targets by that method, the number of poles in contour is incorrectly estimated, and the results are inaccurate. In this paper, a domain difference method for searching complex targets' poles on complex plane is proposed on the criterion, that the second-order differenced logarithm of determinant of coefficient matrix from MoM is local maximum. Numerical results of a conducting sphere are presented to demonstrate the accuracy and capability of the proposed method. Lastly, the poles of a missile model and a plane model are calculated, and compared with those from the Matrix-Pencil (MP) method.