On the field iterative method for modeling of two-dimensional large aperture open-ended cavity

The scattering from air inlets and cavities contributes significantly to the overall radar signature of real targets. One of the well-cited methods for this class of problems is the field iterative method (FIM), first proposed by Reuster and Thiele [1] to compute the scattered electric fields at the aperture of an electrically large perfectly conducting cavity. In this paper, the correct formulations of the FIM for two-dimensional (2D) large aperture open-ended cavity, for both parallel and perpendicular polarization, are presented. The numerical results obtained using the present formulations show that the results are in reasonably good agreement with that of the method of moments, in particular, for small angles of incidence. This is consistent with the Kirchhoff's approximation.