Transformation of the physical optics integral to the boundary integral and its application to metal scattering problems

Abstract

AbstractThe physical optics approximation (PO) is a powerful calculation method in the analysis of the radiation pattern of a reflector antenna and of the radar cross section (RCS). At high frequencies, the computational efficiency of the radiation surface integration is poor. In the present research, a method is proposed in which the radiation surface integral of PO is rigorously transformed to a line integral along the scatterer boundary. Since the line integral is used in this method, the computation time can be reduced in comparison with PO. When the RCS of an arbitrary shape is computed, the shape is often approximated by a combination of planar patches. Therefore, PO and the proposed method are compared with respect to the numerically calculated scattering patterns of a circular disk and a square plate. It is confirmed that these two methods are similar in accuracy. An example of application to a three‐dimensional body is presented. © 2002 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 85(12): 30–37, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.10059