CANADIAN JOURNAL OF PHYSICS, cilt.74, sa.9-10, ss.685-691, 1996 (SCI-Expanded)
E- and H-plane radiation patterns of focus-fed, axially symmetric Gregorian antennas are analyzed using the generalized method of the geometrical theory of diffraction. Only the rim of the main reflector was loaded; in a smoothly tapered manner, but the whole surface of the subreflector was loaded. Loads are defined in terms of surface impedances. With the help of this analysis, the effect of the smoothly tapered rim loading on the far-field radiation patterns of Gregorian antennas can be studied in detail.