A radon transform interpretation of the physical optics integral

Abstract

Physical optics (PO) is a well-known asymptotic technique for evaluating the fields scattered from an object. Evaluation of a surface integral forms the crux of this technique. In this paper, the PO integral is formulated for plane-wave incidence and far-field observation. Then, this integral is converted to the time domain and interpreted as a Radon transform. When the integration domain is a triangle, this interpretation yields a closed-form expression that can be employed in both the frequency and time domains. The efficacy of using the derived closed-form expression in the frequency domain is demonstrated through numerical examples. (C) 2005 Wiley Periodicals, Inc.