PURPOSE:To facilitate the control of the directivity within a perpendicular plane by reflecting a radiated radio wave from an conical primary radiator in a sub-reflecting mirror having a hyperboloid or ellipsoid of revolution and making the radio wave incident in a main reflecting mirror having a conical paraboloid of revolution. CONSTITUTION:In adopting a hyperboloid of revolution for the reflecting plane of revolution, one focus of foci 8, 9 is made coincident with the focus of a parabolic curve 6 of the reflection plane of the main reflecting mirror 1 and the other focus 9 is made coincident with the center of phase of the conical primary radiator 3, the spherical wave radiated from the radiator 3 is reflected in the main reflecting mirror 1 and the plane wave is radiated horizontally with an equal phase from the aperture. Thus, the directivity in the horizontal plane is nondirectional and the directivity in the vertical plane is maximum in the horizontal direction. In varying the shape of the reflecting mirror 1 as shown in dotted lines 10, the directivity with an angle of theta upward in the horizontal direction. In exciting the conical primary radiator 3 by a mode generator 4, a horizontal polarized wave antenna is obtained.
展开▼
