GB1334499A - Antenna system - Google Patents

Abstract

1334499 Aerials; magnetic amplifiers MATSUSHITA ELECTRIC INDUSTRIAL CO Ltd 24 July 1972 [22 July 1971] 34560/72 Headings H4A and H3B An aerial system comprises a magnetic core 7 formed with a plurality of apertures 8, 8<SP>1</SP>, a first coil 12 which is wound on part of the core between the apertures, and which serves as a pumping coil for changing the permeability of said core, two coils 9, 11 with their windings disposed perpendicularly to that of the coil 12 and linked by magnetic flux therefrom, a load connected to the coil 11, and an aerial element connected to the coil 9. All turns of the winding 11 pass through the apertures 8, 8<SP>1</SP>, whereas only a part of the turns of the winding 9 pass through said apertures, the remaining turns thereof being disposed around the whole body of the core 7. Parametric amplification of the signal from the aerial element may be obtained with this system (Figs. 6, 7, not shown). Magnetic biasing may be provided by permanent magnets. These may either be in contact with a face of the core (and if made of ferrite be disposed within coil windings) or be spaced from the core by non- magnetic spacers (Figs. 8 to 13, not shown). An aerial array may be constituted from a plurality of such aerial systems, and the beam therefrom may be steered by suitable adjustment of the amplitude and phase of the pumping current in each system (Fig. 14, not shown).