PURPOSE: To facilitate the adjustment of a direction of a radiation beam and the polarized wave face of a linearly polarized wave by adopting the constitution such that a rotary shaft of a rotating parabolic face is place perpendicularly and a tilt angle of a dielectric plate and a rotating angle are adjusted.

CONSTITUTION: A metallic grating 3 formed by arranging lots of metallic strips with a narrower width than the wavelength of an operating frequency is provided to the inner face of a dielectric body 2 shaped as a rotating parabolic face. A dielectric plate 4 one side of which a metallic film 8 is provided and other side of which a metallic grating 5 formed hy arranging lots of metallic strips with a narrower width than the wavelength of an operating frequency is provided is placed in an inner space of the dielectric body 2. Furthermore, a primary radiator 1 radiating a radio wave of linearly polarized wave from the inner direction of the dielectric body 2 to the outside is provided and the rotating shaft of the rotating parabolic face of the dielectric body 2 is made almost perpendicular. Then the tilt angle and the rotating angle of the dielectric plate 4 are adjusted. Thus, the volume of the antenna system occupied in space is reduced, and the radiating beam direction of the antenna system and the polarized face of the linearly polarized wave are easily adjusted.