GB747505A - Improvements in or relating to aerials - Google Patents

Abstract

747,505. Aerials. ELECTRIC & MUSICAL INDUSTRIES, Ltd. Aug. 17, 1954 [Sept. 1, 1953], No. 24090/53. Class 40 (7). An aerial arrangement for use on two or more frequency bands comprises a resonant conductive aerial such as the sheet metal dipole 1, 2 coupled to a feeder 5 for operation on one frequency band and a slot or slots cut in the conductive aerial and coupled for operation in another band or other bands. As shown, vertical slot 3 is cut in dipole element 1 and coupled over feeder 6 for operation on a second band and a plurality of transverse slots 4 cut in element 2 and coupled as shown to feeder 7 for directive reception on another band. The conductive dipole elements may be tubular instead of flat (Fig. 2, not shown). Fig. 3 shows a conductive unipole element 10 and ground plane 13 coupled to feeder 11, 12. A slot 3 coupled to feeder 6 for operation in a second band is cut in element 10. If desired the slot elements may be provided with parasitic reflecting elements such as the dipole rods 14. All the feeders can be led away separately, but adjacent each other, or they may be combined by the use of suitable networks for operation over a common lead.