3D near field far field correction using the approximations of the physical optic

Abstract

Measurement facilities are not still compact and therefore the measured radar cross section (RCS) is a near field RCS. In order to get a prediction of the far field RCS from near field measurements a near field far field (NFFF) correction must be done. In this paper a NFFF correction using the approximation of Physical Optic is proposed. This method is easy to apply and allows calculating the far field RCS in all the dimensions of the space with good results. This article is divided into three parts. The first part allows to demonstrate how the far field RCS may be calculated from near field measurements under the hypothesis of approximations of the Physical Optic. The second part allows explaining how to implement this theory in the case of real RCS measurements. Finally a demonstration of the results got while applying this method on a target constituted by bright points is presented.