A method for combining integral equation and asymptotic techniques for solving electromagnetic scattering problems
Abstract
A new approach is presented for combining the integral equation and high frequency asymptotic techniques, e.g., the geometrical theory of diffraction. The method takes advantage of the fact that the Fourier transform of the unknown surface current distribution is proportional to the scattered far field. A number of asymptotic methods are currently available that provide good approximation to this far field in a convenient analytic form which is useful for deriving an initial estimate of the Fourier transform of the current distribution. An iterative scheme is developed for systematically improving the initial form of the high frequency asymptotic solution by manipulating the integral equation in the Fourier transform domain. A syntheticaperturedistribution scheme is also developed in which the approximate scattered farfield pattern obtained by asymptotic techniques is improved by systematically correcting the scattered field distribution on an aperture erected in juxtaposition with the obstacle.
 Publication:

NASA STI/Recon Technical Report N
 Pub Date:
 May 1976
 Bibcode:
 1976STIN...7714300K
 Keywords:

 Asymptotic Methods;
 Electromagnetic Scattering;
 Integral Equations;
 Alternating Current;
 Far Fields;
 Fourier Transformation;
 Numerical Analysis;
 Radar Transmission;
 Communications and Radar