Application of the integral equation-asymptotic phase (ie-AP) method to three-dimensional scattering

An approach for numerically analyzing electromagnetic scattering from conve x conducting obstacles which possess large, relatively smooth surfaces is d iscussed in this work. In this approach, the current density induced on the scatterer is represented in terms of basis functions which are capable of representing rapid phase variation with very few unknowns per square wavele ngth. The unknowns associated with the surface current are then determined through testing of appropriate surface integral equations. A special techni que is introduced to accelerate calculations of portions of the resultant m atrix equation associated with shadow regions and edges. The results of a s eries of numerical experiments on canonical objects demonstrate the efficie ncy and accuracy of the technique.