Accuracy demonstration of physical optics with modified surface-normal vectors

In this paper, the simple equivalent surface currents, which are enhanced accuracy of the physical optics (PO) to the level of GTD, were obtained by introducing the modified surface-normal vectors in the PO currents. The effectiveness was numerically demonstrated to the scattering problems for the three-dimensional circular disc, the two-dimensional corner and parabola reflector. This concept is perfectly different from the fringe wave correction. The PO with the modified surface-normal vectors has high versatility owing to the free singularities in the GO boundaries, focus, and caustics