GB378642A - Improvements in or relating to directional wireless radiating systems - Google Patents

Abstract

378,642. Directive wireless signalling. RADIO-AUSTRIA AKT.-GES., 14, Renngasse, Vienna. Aug. 11, 1931, No. 22707. Convention date, March 6. [Class 40 (v).] A directional aerial system comprises groups of coaxial horizontal dipoles arranged one behind the other at a distance of substantially half a wavelength in the main direction of radiation each number of a group being excited cophasially from the wires of a parallel wire feeder with uncrossed conductors and the groups having alternately opposed phases. Groups of dipoles 1, 11, Fig. 1, are arranged at half wavelength intervals apart and excited from a parallel wire system 2, 3 fed through a coupling device 4 and carrying standing voltage waves. The main directions of radiation are shown at X. Two or more such systems may be arranged side by side and fed from a common source. Impedances 6, Fig. 4, or tuning or coupling elements may be inserted in known manner in the individual dipoles or sections 5, Fig. 3, of the dipoles may be bent back upon themselves. The system may be arranged so as to constitute one or more closed loops as in Fig. 4 so that hoar-frost and ice may be dispersed from it by the passage of a heating current, and to ensure constant current intensity of the H.F. currents in all the branches. For compensating any asymmetry and for exact adjustment of the voltage antinodes, loops 9, Fig. 5, of variable magnitude may be provided. The groups of dipoles may be arranged at different heights rising towards the favoured radiation direction which gives an increase in that direction and a decrease in the opposite direction; and also produces radiation at a steeper angle with the ground which is said to be an advantage for long distance communication. The groups may be arranged in planes one above the other and some may be excited by induction.