GB691485A - High frequency antennas - Google Patents

Abstract

691,485. Aerials. ERCOLINO, M. D. Aug. 4, 1950, No. 19622/50. Class 40 (vii). In a wide-band directive aerial system comprising a dipole and spaced parasitic reflector each half of the dipole comprises a V-shaped rod or tubular structure having a horizontal axis with the two arms 27 of the V in a vertical plane, the planes of the two structures being mutually inclined to include an obtuse angle, e.g. 140 degrees, and the reflector comprises four rods 37 disposed as an X in a vertical plane. The embodiment described is for receiving horizontally polarized waves but by a suitable rotation of the system it can be adapted to receive vertically polarized waves. Each V-shaped structure is formed by clamping two rods 27 between two perforated triangular plates having opposed grooves near the edges, Figs. 3-5 (not shown), one of the plates having a bent lug at the apex for attachment to an insulating block mounted at one end of the cross-bar 10 and the reflector rods 37 are mounted at the other end of the cross-bar in a similar manner but the two lugged clamping plates are formed as a single member instead of being separated by insulation. The crossbar is attached to a vertical mast 43 by a U- shaped clamp, Fig. 2 (not shown). If the lengths of the rods 27 and 37 are approximately #/4 at a particular frequency f, the radiation pattern will be substantially constant over a frequency band #-3#, Fig. 6 (not shown).