US 6,388,619 B2 · Dual band antenna

Abstract

A flat-plate dual band array antenna is described which comprises two flat plate arrays of single band antenna elements, each of which operates in a different frequency band. The two flat plate arrays are positioned one above the other, with areas in the upper flat plate array being removed in order that the antenna elements in the lower flat plate array can radiate through the upper flat plate array. The geometric arrangement of the antenna elements is such that distribution networks for the antenna elements can be accommodated in the limited space available. Dual band flat-plate array feeds for a reflector antenna are also described. These use at least two flat-plate arrays that are positioned one above the other. Again regions in the upper flat-plate array are removed to allow the lower flat-plate to operate through the upper one. The geometric arrangement of the antenna elements in these array feeds is such that transmit and receive beams are provided that have co-incident phase centers and approximately equal beamwidths. The flat plate array antenna and reflector antennas described are particularly useful for subscriber satellite communication systems such as satellite TV, with receive signals being in the Ku band and transmit signals being in the Ka band.

Claims15

Dependent claims

A dual band flat plate antenna comprising:

(i) a first flat plate array of first single band antenna elements operable at a first frequency band, said first plate array comprising regions between said first single band antenna elements;
(ii) a second flat plate array of second single band antenna elements operable at a second frequency band different from the first frequency band, said second flat plate array being positioned over said first flat plate array such that said second single band antenna elements overlie said regions of said first plate array;
wherein both the first and second flat plate arrays each comprise a distribution network layer comprising a plurality of probes co-planar with the distribution network layer;
said distribution network layer being positioned under and spaced apart from a plate of electrically conducting material comprising a plurality of apertures positioned such that each aperture is above a probe;
and wherein
(iii) one or more of said regions in said second flat plate array are removed by at least removing parts of the plate of electrically conducting material within that second flat plate array, such that in use, said first single band antenna elements are operable through said second flat plate array.

3 more elements

A dual band flat-plate array feed for a reflector antenna said array feed comprising:

(i) a first flat plate array of first single band antenna elements arranged to operate at a first frequency band said first flat plate array comprising regions between said first single band antenna elements;
(ii) a second flat plate array of second single band antenna elements arranged to operate at a second frequency band, said second flat plate array being positioned over said first flat plate array such that said second single band antenna elements overlie said regions of said first flat plate array;
wherein both the first and second flat plate arrays each comprise a distribution network layer comprising a plurality of probes co-planar with the distribution network layer;
said distribution network layer being positioned under and spaced apart from a plate of electrically conducting material comprising a plurality of apertures positioned such that each aperture is above a probe;
and wherein
(iii) one or more regions in said second flat plate array are removed by at least removing parts of the plate of electrically conducting material within that second flat-plate array, such that in use, said first single band antenna elements are operable through said second flat plate array.

3 more elements

Dependencies are inferred from the claim text.

Dual band antenna

Life of this patent

Dual band antenna

Life of this patent

Abstract

Claims15