An extension of Rusch's asymptotic physical optics diffraction theory of a paraboloid antenna

An extension of Rusch's asymptotic physical optics (APO) diffraction theory as applied to a parabolic antenna is presented. This extension provides a continuous solution throughout the shadow boundary region. The complete field expressions and the associated "new" physical optics diffraction coefficients are derived. Using the solution, the diffraction pattern for a 10-ft diameter focal plane parabola at 6 GHz is calculated.