Wireless communication using an airborne switching node

• US 6,061,562 A
• Filed: 10/30/1997
• Issued: 05/09/2000
• Est. Priority Date: 10/30/1997
• Status: Expired due to Term

• Current Assignee: Raytheon Company (Rtx Corporation)
• Original Assignee: Raytheon Company (Rtx Corporation)
• Inventors: Martin, James N., Langston, J. Leland
• Primary Examiner(s): Le, Thanh Cong
• Assistant Examiner(s): Nguyen, Thuan T.
• Application Number:
  US08/961,385
• Time in Patent Office: 922 Days
• Field of Search: 455/13.3, 455/431, 455/430, 455/427, 455/428, 455/429
• US Class Current: 455/431
• CPC Class Codes: H01Q 21/20 the units being spaced along or adjacent to a curvilinear path slotted waveguide arrays H01Q21/005; circularly or helically slotted waveguides H01Q21/0062
• CPC Class Codes: H01Q 21/205 providing an omnidirectional coverage turnstile aerials H01Q21/26
• CPC Class Codes: H01Q 21/29 Combinations of different interacting antenna units for giving a desired directional characteristic H01Q25/00 takes precedence
• CPC Class Codes: H01Q 3/242 Circumferential scanning
• CPC Class Codes: H04B 7/18504 Aircraft used as relay or high altitude atmospheric platform
• CPC Class Codes: H04B 7/2041 Spot beam multiple access

Abstract

A communication system includes an aircraft supporting an airborne switching node that provides communication services to a variety of ground-based devices located in the service region. The devices include subscriber devices, such as customer premises equipment and business premises equipment, as well as gateway devices.

Claims

1. A system for providing communication to a plurality of devices located in a service region on earth which includes a plurality of cells, comprising an aircraft flying above the service region said aircraft having an airborne switching node which includes an antenna section, said airborne switching node being operable to:

transmit through said antenna section to the service region a plurality of directional beams in respective different directions so that each beam is associated with a respective cell in the service region;

adjust the directions of the beams relative to said aircraft, including compensation for movement of said aircraft relative to the earth; and

receive through said antenna section respective signals transmitted by the plurality of devices located in the service region, and transmit each such received signal on one of the beams to one of the devices other than the device from which that signal was received.

2. The system of claim 1, wherein said airborne switching node includes an adapter that mechanically adjusts the orientation of said antenna section relative to said aircraft under control of said airborne switching node to facilitate the adjustment of the beams relative to said aircraft.

3. The system of claim 2, wherein said adapter is operable to effect tilting movement of said antenna section relative to said aircraft about at least one axis which extends approximately horizontally.

4. The system of claim 2, wherein said adapter is operable to effect rotation of said antenna section relative to said aircraft about an approximately vertical axis.

5. The system of claim 4, wherein said adapter rotates said antenna section so as to maintain a substantially constant compass orientation of said antenna section.

6. The system of claim 2, wherein said antenna section includes at least one phased array antenna which is operable to electronically effect adjustment of the directions of the beams.

7. The system of claim 1, wherein said antenna section includes at least one phased array antenna which is operable to electronically effect adjustment of the directions of the beams.

8. The system of claim 1, wherein said antenna section includes a plurality of antenna portions which are each associated with and handle the devices in a respective subset of the cells in the service region.

9. The system of claim 8, wherein each said antenna portion includes a transmit antenna and a receive antenna.

10. The system of claim 5, wherein said antenna section includes a platform having a central section with an angled rim extending therearound, one of said antenna portions being supported on said central section, and other said antenna portions being supported on said angled rim at spaced locations therealong.

11. The system of claim 10, wherein:

said antenna portion mounted on said center section is operable to direct beams to cells in a center of the service area; and

said antenna portions mounted on said angled rim are operable to direct beams to respective sets of cells surrounding the center of the service region.

12. The system of claim 1, wherein said airborne switching node includes a packet switch that receives packet data through said antenna section from a first of the devices in the service region, and directs the packet data to said antenna section for transmission to a second of the devices in the service region.

13. The system of claim 1, wherein said airborne switching node includes:

a memory that stores an association between the beams and the cells, said airborne switching node updating the association in said memory upon performing a handoff of a beam between cells; and

a packet switch that receives packet data though said antenna section from a first of the devices located in one of the cells, accesses said memory to determine a destination beam associated with a second of the devices located in one of the cells, and directs the packet data to said antenna section for transmission to the second device using the destination beam.

14. The system of claim 1, wherein the devices include:

a plurality of subscriber devices that each communicate with said airborne switching node using one of a plurality of first frequency bands; and

a gateway device that communicates with said airborne switching node using a second frequency band different from the first frequency bands.

15. The system of claim 14, wherein said antenna section includes a first portion which facilitates communication with the subscriber devices using phased array technology, and a second portion separate from the first portion which facilitates communication with the gateway device using technology other than phased array technology.

16. The system of claim 1, wherein said airborne switching node communicates with the devices using a frequency band designated for ground-based communication.

17. The system of claim 1, wherein said airborne switching node further includes a pilot transmitter that transmits a pilot signal, and wherein at least one of the devices includes:

an antenna to receive the pilot signal; and

an antenna tracker to position the antenna to point at the airborne switching node in response to the pilot signal.

18. The system of claim 1, wherein said antenna section is operable to facilitate simultaneous transmission of each of the plurality of directional beams.

19. The system of claim 1, wherein said airborne switching node is operable to communicate with a satellite.

20. The system of claim 1, including a further aircraft having thereon a further airborne switching node which provides communication to a plurality of further devices located in a further service region, said airborne switching nodes being operable to communicate with each other.

21. A system for providing communication to a plurality of devices located in a service region on earth, comprising an aircraft flying above the service region, said aircraft having an airborne switching node which includes an antenna section, said airborne switching node being operable to:

transmit through said antenna section to the service region a plurality of directional beams in respective different directions;

hand off each of the devices in the service region from beam to beam as needed to compensate for movement of said aircraft relative to the earth; and

receive through said antenna section respective signals transmitted by the plurality of devices located in the service region, and transmit each such received signal on one of the beams to one of the devices other than the device from which that signal was received.

22. The system of claim 21, wherein said antenna section includes phased array technology and is operable to electronically direct the beams in their respective directions.

23. The system of claim 21, wherein said airborne switching node includes a packet switch that receives packet data through said antenna section from a first of the devices in the service region, and directs the packet data to said antenna section for transmission to a second of the devices in the service region.

24. The system of claim 21, wherein said airborne switching node includes:

a memory that stores an association between the beams and the devices, said airborne switching node updating the association in said memory upon performing a handoff of a device between beams; and

a packet switch that receives packet data through said antenna section from a first one of the devices, accesses said memory to determine a destination beam associated with a second one of the devices, and directs the packet data to said antenna section for transmission to the second device using the destination beam.

25. The system of claim 21, wherein said airborne switching node communicates with the devices using a frequency band designated for ground-based communication.

26. The system of claim 21, wherein said airborne switching node includes a pilot transmitter that transmits a pilot signal to enable ground-based antenna tracking.

27. The system of claim 21, wherein said antenna section includes a plurality of antenna portions, and includes a platform having a central section with an angled rim extending therearound, said central section having thereon one of said antenna portions which facilitates communication with a central portion of the service region, and said angled rim having thereon at spaced locations therealong a plurality of the antenna portions which each facilitate communication with respective portions of the service region disposed around the central portion thereof.

28. The system of claim 27, wherein each of said antenna portions includes a transmit antenna and a receive antenna.

29. The system of claim 21, wherein said antenna section is operable to facilitate simultaneous transmission of each of the plurality of directional beams.

30. The system of claim 21, wherein said airborne switching node is operable to communicate with a satellite.

31. The system of claim 21, including a further aircraft having thereon a further airborne switching node which provides communication to a plurality of further devices located in a further service region, said airborne switching nodes being operable to communicate with each other.

32. The system of claim 21, wherein said airborne switching node includes an adapter that mechanically adjusts the orientation of said antenna section relative to said aircraft under control of said airborne switching node to facilitate the adjustment of the beams relative to said aircraft.

33. The system of claim 21, wherein the devices include a plurality of subscriber devices that each communicate with said airborne switching node using one of a plurality of first frequency bands, and a gateway device that communicates with said airborne switching node using a second frequency band different from the first frequency bands;

said antenna section including a first portion which facilitates communication with the subscriber devices using phased array technology, and a second portion separate from the first portion which facilitates communication with the gateway device using technology other than phased array technology.

34. A method for providing communication to a plurality of devices located in a service region which is on earth and which includes a plurality of cells, comprising the steps of:

flying an aircraft above the service region, said aircraft having an airborne switching node that includes an antenna section;

transmitting through said antenna section a plurality of directional beams in respective different directions to the service region, so that each beam is associated with a respective cell in the service region;

adjusting the directions of the beams relative to said aircraft, including compensation for movement of said aircraft relative to the earth; and

receiving through said antenna section respective signals transmitted by the plurality of devices located in the service region, and transmitting each such received signal on one of the beams to one of the devices other than the device from which that signal was received.

35. The method of claim 34, wherein said adjusting step includes the step of electronically adjusting the directions of the beams relative to said aircraft.

36. The method of claim 34, wherein said adjusting step includes the step of mechanically adjusting the orientation of said antenna section relative to said aircraft to adjust the directions of the beams relative to said aircraft.

37. The method of claim 36, wherein said mechanically adjusting step includes the step of rotating said antenna section relative to said aircraft so as to maintain a substantially constant compass orientation of said antenna section.

38. The method of claim 34, wherein said airborne switching node includes a memory storing an association between the beams and the cells, and including the step of updating the association in said memory upon performing a handoff of a beam between cells.

39. The method of claim 34, including the step of causing said antenna section to communicate with the devices using a frequency band designated for ground-based communication.

40. The method of claim 34, further comprising the step of causing said antenna section to transmit a pilot signal to enable ground-based antenna tracking.

41. The method of claim 34, wherein the devices include a plurality of subscriber devices and a gateway device;

and including the steps of;

causing the subscriber devices to each communicate with said airborne switching node using one of a plurality of first frequency bands; and

causing the gateway device to communicate with said airborne switching node using a second frequency band different from the first frequency bands.

42. A method according to claim 34, including the step of causing said antenna section to facilitate simultaneous transmission of each of the plurality of directional beams.

43. A method for providing communication to a plurality of devices located in a service region on earth, comprising the steps of:

flying an aircraft above the service region, said aircraft having an airborne switching node which includes an antenna section;

transmitting through said antenna section to the service region a plurality of directional beams in respective different directions;

handing off each of the devices in the service region from beam to beam as needed to compensate for movement of said aircraft relative to the earth; and

receiving through said antenna section respective signals transmitted by the plurality of devices located in the service region, and transmitting each such received signal on one of the beams to one of the devices other than the device from which that signal was received.

44. The method of claim 43, wherein said antenna section includes phased array technology, and including the step of electronically directing the beams in their respective directions.

45. The method of claim 43, wherein said airborne switching node includes a memory storing an association between the beams and the devices, and including the step of updating the association in said memory upon performing a handoff of a device between beams.

46. The method of claim 43, including the step of causing said airborne switching node to communicate with the devices using a frequency band designated for ground-based communication.

47. The method of claim 43, including the step of causing said antenna section to transmit a pilot signal to enable ground-based antenna tracking.

48. The system of claim 43, including the step of causing said antenna section to facilitate simultaneous transmission of each of the plurality of directional beams.