A technique to combine the geometrical theory of diffraction and the moment method

For many years, The Geometrical Theory of Difraction (GTD) has been applied to antenna and scattering problems for which the structure is large in terms of wavelength. GTD solutions have mainly been concerned with pattern computations with little information concerning antenna impedance and/or aperture distributions. This is especially true for wire-type antennas. On the other hand, The Method of Moment (MM) has been applied to such problems for which the structure is small in terms of wavelength. This paper presents a technique which can be used to combine these two solutions such that a whole host of new problems can be handled.