Abstract:
Kobayashi potential method has successfully been applied to potential as well as scattering geometries
containing perfect electrically conducting (PEC) objects by many investigators. The purpose of present
study is to extend Kobayashi potential method to study the scattering from non-PEC objects hence, to
enhance the applicability of the method. First, geometries containing strip are considered and diffracted
fields have been determined from an impedance strip, from a strip placed at dielectric slab and from a
perfectly electromagnetic conducting (PEMC) strip. Then slit geometries are included. And studies are
conducted to analyze the diffraction from an impedance slit placed at the interface of two different media,
from two parallel slits in an impedance plane and from a slit in PEMC plane.
While applying this method to above type of problems, diffracted fields are considered in terms of unknown
weighting functions. Imposition of boundary conditions give dual integral equations. These dual integral
equations are then used to decide the nature of weighting functions by using the discontinuous properties of
Weber-Schafheitlin’s integral. Edge conditions are also taken into account at this moment. Finally, matrix
equations are obtained to evaluate the expansion coefficients. The elements of these matrix equations are the
infinite integrals and are usually, very complex in nature and hard to solve analytically. So these integrals
and the matrix equations are then solved numerically for unknown expansion coefficients.
Diffracted fields are presented for each geometry. Their dependence on different parameters like angle
of incidence, slit/ strip size, impedance of plane, relative permittivity of the surrounding media has been
discussed and analyzed. Comparison with physical optics is also presented in some problems to validate the
presented results.
