Patent ID: 6597322
Filing Date: 2003-07-22
Classification: H01Q

Abstract:
A primary radiator comprising:a base part in an upper surface of which a groove having a width of Â½ to {fraction (1/1)} of signal wavelength of a high frequency signal and a depth approximately equal to Â¼ of the signal wavelength, and whose inner wall is formed of an electrically conductive material, is formed as a waveguide for the high frequency signal; and a moving part formed of an electrically conductive material and placed above the upper surface of the base part in such a manner as to cover the groove, the moving part including a coupling window for an electromagnetic wave of the high frequency signal, the coupling window being positioned above the groove, and a reflecting member that is formed on a lower surface of the moving part in such a manner as to fit in a cross section of the groove and is positioned away from the coupling window by &frac18; to {fraction (1/1)} of guide wavelength of the high frequency signal, and whose thickness in a longitudinal direction of the groove is not smaller than {fraction (1/10)} of the guide wavelength, wherein the coupling window and the reflecting member are together movable along the groove in the longitudinal direction, and the electromagnetic wave of the high frequency signal propagated through the waveguide formed by the groove and the lower surface of the moving part is radiated through the coupling window.