Variable permittivity dielectric material loaded stepped-horn antenna

where Ywg is the admittance matrix for waveguide region and its size is NM x NM , withelements defined as.. ..and Y hs is the admittance matrix for half-space region and its size is NM x NM and itselements areand Iim is an excitation vector with size NM x I. Its elements areIn the method of moments solution, the aperture is subdivided into Lx and Ly segmentsin the x and y directions, respectively, resulting in patches of size AxAy. Two orthogonallypolarized sets of overlapping rooftop basis functions Mxn and /11,g, are used to model themagnetic surface currents across the aperture (2.39), as shown in Figure 2.8. The totalnumber of expansion functions is NM = (Lx — 1)Ly + (Ly — 1)Lx .The set of x directedmagnetic current basis functions Mxn and the set of y directed magnetic current basisfunction Ay are defined by