| 摘要 |
PURPOSE:To obtain a small-sized parabolic antenna which has a simple structure and a sufficient performance and has a primary radiator suitable for circular polarized waves, by combining an axially symmetrical waveguide and a reflective conductor by die casting or the like. CONSTITUTION:A tip part 2 of an axially symmetrical round waveguide 1 is cut by the face perpendicular to the axis. A reflective face 4 of a reflective conductor 3 is arranged oppositely to the tip face with a gap D1 for the tip 2. the reflective face 4 is connected to a conductor face 4' which covers a conductor face 5 on the outside circumference of the waveguide 1 by holding a gap D2, and the inside conductor face of the reflective conductor 3 is formed into an axially symmetrical recess. Electromagnetic waves in the waveguide are radiated through gaps D1 and D2 from an aperture face 6 to a reflective face 7 of the parabolic antenna. A corner 8 is provided in the aperture part for determining the radiation directivity of the primary radiator, and the directional pattern is adjusted by the size and the angle of the corner 8. |
