GB683732A - Improvements in or relating to wireless aerials - Google Patents

Abstract

683,732. Aerials. RADIO - INDUSTRIE SOC. ANON. Dec. 20, 1950 [Jan. 18, 1950], No. 31035/50. Class 40 (vii). An aerial of the kind comprising at least a pair of radiators energized in phase opposition consists of a rigid conducting mast to which is attached one conductor of a feeder pair, a rigid conductive coaxial sleeve to which is attached the other conductor of the feeder, the sleeve being shorted at one of its ends to the mast and being a quarter of the operating wavelength long or an odd multiple thereof, a first half-wave radiator fixed to the free edge of the sleeve and a second half-wave radiator fixed to the mast along a line neighbouring the edge of the sleeve, both of said radiators being of the same overall revolution shape about the mast axis and diverging in opposite directions so that their remote ends are each a quarter wavelength, or an odd multiple thereof, distant from the mast. and joined to the mast by conductive supports, Figs. 1 and 2 show respectively the energization of the upper and lower radiators 5 of the complete aerial supported by mast 1 and fed through sleeve 2 by coaxial line 3, 4. A complete aerial having differently-shaped radiators 9, 10 is shown in Fig. 4. A number of aerial units may be stacked one above the other with a narrow gap between the end conductive supports of each, in which case only one sleeve need be energized the other aerial units being coupled by the quarter wavelength line formed by the gaps. The feeder may be placed inside the mast.