Point-to-multipoint communications system and method

• US 7,636,552 B2
• Filed: 12/21/2005
• Issued: 12/22/2009
• Est. Priority Date: 04/08/2005
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Monk, Anthony D
• Primary Examiner(s): PHAM, TUAN
• Application Number:
  US11/314,641
• Publication Number:
  US 20060229103A1
• Time in Patent Office: 1,462 Days
• Field of Search: 455/562.1, 455/63.4, 455/69, 455/431, 455/432.1, 455/436, 455/437, 455/439, 455/440, 455/441, 455/442, 455/443, 455/452.2, 342/359, 342/357.08, 342/357.14, 342/372, 342/373, 342/377, 342/383
• US Class Current: 455/63.4
• CPC Class Codes: H01Q 1/283 Blade, stub antennas
• CPC Class Codes: H01Q 1/3208 characterised by the application wherein the antenna is used
• CPC Class Codes: H01Q 19/192 with dual offset reflectors
• CPC Class Codes: H01Q 3/2658 Phased-array fed focussing structure
• CPC Class Codes: H04B 7/18506 Communications with or from aircraft, i.e. aeronautical mobile service
• CPC Class Codes: H04W 36/083 wherein at least one of the access points is a moving node
• CPC Class Codes: H04W 36/18 for allowing seamless reselection, e.g. soft reselection
• CPC Class Codes: H04W 84/06 Airborne or Satellite Networks space-based or airborne stations H04B7/185

Abstract

A point-to-multipoint communications system. The system uses an antenna to generate a single beam having independently steerable, narrow lobes. The phase array and amplitude array distributions used to form the lobes are controlled so that the lobes track and provide full duplex communication links with two or more RF terminals in two or more remote locations. In certain embodiments the dual lobe beam is generated from a fixed, ground-based location, and in other embodiments the single beam is generated from an airborne mobile platform, a mobile land vehicle, or a marine vessel. The various embodiments all enable one, two or more full duplex communication links to be established and maintained with a single beam.

Claims

1. A point-to-multipoint communications system comprising;

an electromagnetic wave antenna system for generating at least a pair of independently steerable lobes from a single beam, said lobes being used to communicate independently with a plurality of remotely located terminals; and

the lobes being controllable by the system so that one of the pair may be faded out while the other of the pair is increased in strength, so that an existing first communication link with a first one of the remote terminals may be interrupted while a second communication link with a second one of the remote terminals is established.

2. The system of claim 1, the single beam comprising a transmit beam.

3. The system of claim 1, the single beam comprising a receive beam.

4. The system of claim 1, the antenna system comprising an antenna aperture having a plurality of independent antenna elements;

and

a beam former in communication with the antenna aperture for controlling signals transmitted by each said antenna element to form said pair of independently steerable lobes from said single transmit beam.

5. The system of claim 1, said antenna system comprising:

an antenna aperture having a plurality of independent antenna elements; and

a beam former in communication with said antenna aperture for controlling each said antenna element to form said pair of independently steerable lobes from said receive beam.

6. The system of claim 1, said antenna system comprising:

an antenna aperture; and

a beam former that controls said antenna system to form said independently steerable lobes.

7. The system of claim 1, said antenna system comprising a phased array antenna aperture.

8. The system of claim 1, said antenna system comprising a hybrid antenna aperture including a parabolic reflector, a parabolic subreflector, and a feed array having a plurality of independent array elements.

9. A point-to-multipoint electromagnetic wave communications system, comprising:

an antenna aperture having a plurality of independent antenna elements;

a beam former for controlling said elements to form a single beam having a plurality of independently steerable lobes to communicate with a plurality of independent, remotely located terminals; and

one of the lobes further being controlled so as to be faded out to interrupt an existing communication link with a first one of the remotely located terminals, while a second one of the lobes is increased in strength to establish a new communications link with a second one of the remotely located terminals.

10. The system of claim 9, said antenna aperture comprising a transmit aperture to radiate electromagnetic wave signals via said independently steerable lobes of said single beam.

11. The system of claim 9, said antenna aperture comprising a receive aperture to receive electromagnetic wave signals via said independently steerable lobes of said single beam.

12. The system of claim 9, said antenna aperture comprising a phased array antenna aperture.

13. The system of claim 9, said antenna aperture comprising:

a parabolic reflector;

a parabolic subreflector; and

a feed structure including said plurality of independent elements.

14. The system of claim 9, said beam former including:

a plurality of phase shifters, one being associated with each said antenna element; and

a plurality of attenuators, one being associated with each said antenna element.

15. The system of claim 14, said beam former including components to control a signal gain associated with each of said independently steerable lobes so that different signal gains are provided for each of said steerable lobes.

16. A method for point-to-multipoint communications comprising:

generating a single beam having at least a pair of distinct, independently steerable lobes;

using an antenna to at least one of radiate and receive electromagnetic wave signals via said independently steerable lobes; and

using the independently steerable lobes to fade out an existing communication link provided by a first one of the steerable lobes with a first remotely located terminal, while increasing the strength of a second one of the lobes to establish a new communication link with a second remotely located terminal remote from the first remotely located terminal.

17. The method of claim 16, further comprising independently controlling a signal gain associated with each of said lobes to enable communication via said independently steerable lobes with different, remotely located communication terminals at different data rates.

18. The method of claim 16, further comprising generating said beam from a ground-based location.

19. The method of claim 16, further comprising generating said beam from an airborne mobile platform.

20. The method of claim 16, further comprising generating said beam from a marine vessel.