| 摘要 |
976,334. Aerial systems. MARCONI CO. Ltd. July 19, 1961 [Nov. 25, 1960], No. 40576/60. Heading H4A. A receiving aerial system suitable for use in a satellite re-broadcasting station and adapted to receive desired polarized signals at a first frequency and to reject signals at a second, different, frequency incoming in a direction perpendicular to the polarization of said desired signals comprises two plane polarized component aerials spaced in a predetermined direction by a predetermined number of half wavelengths at said second frequency and means for connecting said aerials to a common feed point so that signals reaching the system from a direction in the plane of polarization are in phase at said feed point and signals for a direction perpendicular to said plane of polarization are in phase opposition at said feed point. In order to receive horizontally polarized signals of wavelength # from a horizontal direction and reject such signals from a vertical direction, dipoles or dipole arrays 1, 2, Fig. 1, are arranged in a vertical plane with dimension d = #/2. In a second embodiment, Fig. 3, the elements 1, 2 are in a horizontal plane and separated in the reception direction by a distance #/2 and are displaced perpendicular to this direction by a distance s##. The elements are connected to a common feed point 3 by leads differing in length by a distance p = (2n + 1)#/2 where n is integral. In modifications, dimensions s and l may be zero. The aerial system may be mounted vertically below a transmitting aerial for a satallite re-broadcasting system. |
