Perfectionnements aux ensembles d'antennes directives

586,035. Aerials ; directive radio systems. STANDARD TELEPHONES & CABLES, Ltd. June 2, 1944, No. 10681. Convention date, July 9, 1943. [Class 40 (v)] A directional aerial comprises a bent-armed dipole in which each radiating arm 22, 24 Fig. 1, consists of an inner portion and an outer portion inclined at an angle to each other, the inner portion of one arm being colinear with the inner portion of the other, and a linear reflector 40 arranged “ wavelength from the colinear inner portions of the radiating arms, the whole system lying in a common plane. The length of each arm, and that of the reflector, is ¢ wavelength. Two of such dipole systems may be arranged one above the other in such a manner that their field patterns combine to form a glide path for landing aircraft, especially as described in Specification 546,668. The two systems are spaced ¢ wavelength apart and energised in phase co-incidence through a transmission line perpendicular to the parallel planes in which the systems lie. The arms 22, 24 (36, 38) terminate in insulating members 26 which are clamped in a junction box 18 (20) by means of a nut 30. The pairs of dipole systems are carried by a rectangular frame comprising a vertical spacing member 6 at the rear, having clamps 14, 16 by which the structure may be mounted on pole 2, horizontal members 8, 10 supporting the junction boxes 18, 20, and a vertical spacing tube at the front through which the transmission line 46, 48 extends.