Patent ID: 6020859
Filing Date: 2000-02-01
Classification: H01Q

Abstract:
In an antenna system, a reflector in a feed element for radiating and intercepting electromagnetic waves, comprising:a) a main reflector; andb) a self-supported waveguide feed element located along the axis which passes through the center of said main reflector, said feed element including;1) a support-tube which has a first, inner end attached to the center of said main reflector and a second, outer end located near the focal region of the reflector;2) a waveguide in said tube;3) a sub-reflector located outside said second, outer end of said tube and said waveguide, said sub-reflector having a diameter larger than said second, outer end of said support-tube;4) a gap provided between said sub-reflector and said second, outer end of said tube;5) said sub-reflector consisting of reflective material with a plurality of rotationally symmetric grooves; and6) said plurality of grooves of said sub-reflector which are located outside a diameter equal to the diameter of said support-tube being filled with a dielectric material.