RCS code for large obstacles using PTD-TC

We have developed a calculation method for the RCS of large obstacle illuminated by a plane wave. When the size of the scatterer is large with respect to the wavelength, the Physical Optics (PO) approximation method is known to be a powerful approach for predicting diffracted or radiated fields. However, conventional PO has an unreliable feature caused by Geometrical Optics (GO) currents. Here we present a method that approximates an impedance surface patch as a quadric in order to shorten computing time and considers electromagnetic transition currents determined from the canonical problem, wedge and/or smooth convex, to improve accuracy. We then report RCS calculation software for large complex obstacles like an automobile.