Primary radiator and antenna apparatus

摘要

Disclosed is a primary radiator in which a central portion (3) of a subreflector (2) is formed in a conical shape, grooves (4) extending, in relation to their depth direction, parallel to an axis of a circular waveguide (1) are formed cylindrically in a surrounding portion of the subreflector (2) surrounding the central portion (3) formed in a conical shape, and a portion extending from the grooves (4) formed in the surrounding portion of the subreflector (2) to a peripheral portion (5) of the subreflector (2) has a sloped structure which is formed in such a way that the peripheral portion (5) projects toward the circular waveguide (1).