Phased array antenna apparatus

• US 6,396,440 B1
• Filed: 06/24/1998
• Issued: 05/28/2002
• Est. Priority Date: 06/26/1997
• Status: Expired due to Fees

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Chen, Shuguang
• Primary Examiner(s): Wong, Don
• Assistant Examiner(s): Nguyen, Hoang
• Application Number:
  US09/103,739
• Time in Patent Office: 1,434 Days
• Field of Search: 343/700 MS File,853,767-771
• US Class Current: 343/700.0MS
• CPC Class Codes: H01Q 21/0012 Radial guide fed arrays
• CPC Class Codes: H01Q 3/26 varying the relative phase or relative amplitude of energisation between two or more active radiating elements; varying the distribution of energy across a radiating aperture H01Q3/12, H01Q3/22, H01Q3/24 take precedence

Abstract

A phased array antenna apparatus includes a plurality of radiation elements, a power supply unit, a power distributor, a feed probe, a plurality of electromagnetic coupling units, and a plurality of phase shifters. The radiation elements are aligned and arranged to be electromagnetically driven. The power supply units supply power to the radiation elements. The power distributor has a pair of conductive plates arranged to be parallel to each other and acts as a radial waveguide distributing the power supplied from the power supply unit to the radiation elements. The feed probe is arranged on one of the conductive plates to radiate an electromagnetic wave into the radial waveguide in accordance with the power supplied from the power supply unit. The electromagnetic coupling units are arranged on the other conductive plate in correspondence with the radiation elements to extract the electromagnetic wave radiated from the feed probe and propagating through the radial waveguide by electromagnetic coupling. The phase shifters control a phase of the electromagnetic wave extracted by the electromagnetic coupling units and supply the electromagnetic wave to the radiation elements.

Claims

1. A phased array antenna apparatus comprising:

a plurality of radiation elements aligned and arranged to be electromagnetically driven;

a power supply which supplies power to said radiation elements;

a power distributor which distributes power supplied from said power supply to said radiation elements, said power distributor having a pair of conductive plates arranged parallel to each other thereby forming a radial waveguide;

a feed probe arranged on one of said conductive plates to radiate an electromagnetic wave into said radial waveguide in accordance with said power supplied from said power supply;

a plurality of electromagnetic couplers arranged on the other of said conductive plates in correspondence with said radiation elements, said electromagnetic couplers extracting the electromagnetic wave radiated from said feed probe, said electromagnetic couplers being in the form of openings disposed within said other of said conductive plates, said openings having an area which increases as a distance between a respective coupler and said feed probe increases; and

a plurality of phase shifters which control a phase of the electromagnetic wave extracted by said electromagnetic couplers and which supply the electromagnetic wave to said radiation elements.

2. An apparatus according to claim 1, wherein said openings have a rectangular cross-section with a long side extending in a direction approximately perpendicular to a radius of a circle centered on said feed probe, and

the long side of said opening increases as the distance from said feed probe increases.

3. An apparatus according to claim 1, wherein each of said electromagnetic couplers comprises a coupling probe having one end connected to a corresponding phase shifter and an other end projecting into said radial waveguide.

4. The phased array antenna apparatus as claimed in claim 3, wherein:

a length of the other end of said coupling probe which projects into said radial waveguide increases as a distance from said feed probe to a respective coupling probe increases.

5. An apparatus according to claim 1, wherein said apparatus further comprises:

a controller which calculates a transmitted phase of the electromagnetic wave on the basis of a positional relationship between said radiation elements, said feed probe, and a frequency to be used in said electromagnetic wave, and

said phase shifter controls the phase of the electromagnetic wave in accordance with said transmitted phase from said controller.

6. An apparatus according to claim 5, wherein:

said controller calculates the transmitted phase and a transmitted amplitude of the electromagnetic wave on the basis of the positional relationship between said radiation elements, said feed probe, and the frequency to be used in said electromagnetic wave, and

said phase shifter controls the phase and an amplitude of the electromagnetic wave in accordance with said transmitted phase and said transmitted amplitude output from said controller.

7. An apparatus according to claim 1, wherein each said radiation element comprises a circular microstrip patch antenna, and

said phase shifter comprises a digital phase shifter.

8. An apparatus according to claim 1, wherein said apparatus further comprises:

an electromagnetic coupling layer stacked on said radial waveguide and having said electromagnetic couplers,

a phase control layer stacked on said electromagnetic coupling layer and having said phase shifter, and

a radiation element layer stacked on said phase control layer and having said radiation elements, thereby forming an antenna.

9. An antenna apparatus comprising:

a plurality of radiation elements;

a waveguide having a feed probe; and

a plurality of electromagnetic couplers in the form of openings disposed on said waveguide and providing electromagnetic access between said radiation elements and said waveguide;

wherein said openings each have an area which increases as a distance between a respective electromagnetic coupler and said feed probe increases.

10. The antenna apparatus as claimed in claim 9 further comprising:

an electromagnetic source feeding said feed probe;

a plurality of phase shifters which control a phase of an electromagnetic wave created by said electromagnetic source, said phase shifters being disposed between said electromagnetic couplers and said radiation elements.

11. The antenna apparatus as claimed in claim 9 wherein:

said openings have a rectangular cross-section with a long side extending in a direction approximately perpendicular to a radius of a circle centered on said electromagnetic source, and

the long side of said openings increases as the distance between a coupler and said feed probe increases.

12. The antenna apparatus as claimed in claim 9 wherein each of said electromagnetic couplers comprises a coupling probe having one end connected to a corresponding radiation element and an other end projecting into said waveguide.

13. The antenna apparatus as claimed in claim 12 wherein a length of the other end of said coupling probe which projects into said waveguide increases as a distance from said feed probe to a respective coupling probe increases.

14. The antenna apparatus as claimed in claim 13 further comprising:

an electromagnetic source which feeds said feed probe; and

a plurality of phase shifters which control a phase of an electromagnetic wave created by said electromagnetic source, said phase shifters being disposed between said electromagnetic couplers and said radiation elements;

wherein

said openings have a rectangular cross-section with a long side extending in a direction approximately perpendicular to a radius of a circle centered on said electromagnetic source, and

the long side of said openings increases as the distance between a respective coupler and said electromagnetic source increases.

15. An antenna apparatus comprising:

a waveguide adapted to transmit electromagnetic energy, said electromagnetic energy varying in amplitude at different positions along said waveguide;

a plurality of radiation elements; and

a plurality of electromagnetic couplers coupling different portions of said waveguide to said radiation elements, said electromagnetic couplers being in the form of openings, said openings having a rectangular cross-section with a long side extending in a direction approximately perpendicular to a radius of a circle centered on an electromagnetic source supplying said electromagnetic energy, said long side of said openings increases as the distance between a coupler and said electromagnetic source increases, wherein said electromagnetic couplers are arranged so as to provide each of said radiation elements with substantially the same amount of electromagnetic energy.

16. The antenna apparatus as claimed in claim 15 further comprising

a plurality of phase shifters which control a phase of an electromagnetic wave created by said electromagnetic source, said phase shifters being disposed between said electromagnetic couplers and said radiation elements.

17. The antenna apparatus as claimed in claim 16 wherein there is the same number of radiation elements, electromagnetic couplers, and phase shifters.

18. The antenna apparatus as claimed in claim 15 wherein a number of electromagnetic couplers equals a number of radiation elements.

19. An antenna apparatus comprising:

a waveguide adapted to transmit electromagnetic energy, said electromagnetic energy varying in amplitude at different positions along said waveguide;

a plurality of radiation elements; and

a plurality of electromagnetic couplers coupling different portions of said waveguide to said radiation elements, wherein said electromagnetic couplers are arranged so as to provide each of said radiation elements with substantially the same amount of electromagnetic energy;

an electromagnetic source feeding said waveguide and having a feed probe; and

a plurality of phase shifters which control a phase of an electromagnetic wave created by said electromagnetic source, said phase shifters being disposed between said electromagnetic couplers and said radiation elements;

wherein

said electromagnetic couplers are in the form of openings;

said openings have a rectangular cross-section with a long side extending in a direction approximately perpendicular to a radius of a circle centered on said electromagnetic source, and

the long side of said openings increases as the distance between a respective coupler and said electromagnetic source increases.