| 摘要 |
<P>PROBLEM TO BE SOLVED: To enable acquisition of a rotationally symmetrical radiation characteristic irrespective of the frequency of a radio wave, without enlarging the diameter of a sub-reflector, and to suppress unnecessary radio wave radiation to the back face of the sub-reflector. <P>SOLUTION: A center portion 3 of a sub-reflector 2 has a conical formation. In the periphery of the center portion 3 of the conical formation, a vertical groove 4 is formed in a cylindrical shape in parallel to the axis of a circular waveguide 1. A portion from the vertical groove 4 formed in the periphery of the center portion 3 to an outer peripheral portion 5 has an inclined structure 6 in such a manner that an outer peripheral portion 5 of the sub-reflector 2 protrudes on the circular waveguide 1 side. <P>COPYRIGHT: (C)2013,JPO&INPIT |
