System for managing the multiple air-to-ground communications links originating from each aircraft in an air-to-ground cellular communication network

• US 20080102814A1
• Filed: 10/31/2006
• Published: 05/01/2008
• Est. Priority Date: 10/31/2006
• Status: Active Grant

• Current Assignee: Gogo Business Aviation LLC (GOGO Incorporated)
• Original Assignee: Aircell LLC (GOGO Incorporated)
• Inventors: Liu, Yong, Chari, Anand K., Walsh, Patrick J., Saroka, Harold G., Joyce, Tim, McKenna, Daniel B.
• Granted Patent: US 7,920,860 B2
• Time in Patent Office: Days
• US Class Current: 455/424
• CPC Class Codes: H01Q 1/283 Blade, stub antennas
• 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 9/0435 using two feed points
• CPC Class Codes: H01Q 9/32 Vertical arrangement of element H01Q9/40 takes precedence
• CPC Class Codes: H04B 7/10 Polarisation diversity; Directional diversity
• CPC Class Codes: H04B 7/18506 Communications with or from aircraft, i.e. aeronautical mobile service
• CPC Class Codes: H04W 16/28 using beam steering
• CPC Class Codes: H04W 84/005 Moving wireless networks

Abstract

The Multi-Link Aircraft Cellular System makes use of multiple physically separated antennas mounted on the aircraft, as well as the use of additional optional signal isolation and optimization techniques to improve the call handling capacity of the Air-To-Ground cellular communications network. These additional techniques can include polarization domain and ground antenna pattern shaping (in azimuth, in elevation, or in both planes). Further, if code domain separation is added, dramatic increases in capacity are realized. Thus, the Air-To-Ground cellular communications network can increase its capacity on a per aircraft basis by sharing its traffic load among more than one cell or sector and by making use of multiple physically separated antennas mounted on the aircraft, as well as the use of additional optional signal isolation and optimization techniques.

Claims

1. A system for managing radio frequency communications in a non-terrestrial region of space between a plurality of wireless subscriber devices located in each of a plurality of aircraft and a plurality of Air-To-Ground terrestrial base stations of an Air-To-Ground cellular communications network, comprising:

a plurality of radio frequency antennas mounted on the exterior surface of each of said aircraft;

interconnect means, located in each of said aircraft, for selectively applying said radio frequency communication signals onto selected ones of said plurality of radio frequency antennas to simultaneously maintain multiple Air-To-Ground Radio Frequency communications links with selected ones of said plurality of Air-To-Ground terrestrial base stations of said Air-To-Ground cellular communications network;

a plurality of Air-To-Ground terrestrial base stations of said Air-To-Ground cellular communications network for populating said non-terrestrial region of space with a plurality of multi-dimensional Radio Frequency sectors, each having a plurality of radio frequency characteristics, to exchange call traffic between said plurality of wireless subscriber devices and said Air-To-Ground cellular communications network; and

connection management means for identifying a correspondence between selected ones of said aircraft radio frequency antennas and selected ones of said plurality of multi-dimensional Radio Frequency sectors to establish said Air-To-Ground Radio Frequency communications link.

2. The system for managing radio frequency communications of claim 1 wherein said connection management means comprises:

pilot signal determining means, located in each of said aircraft, for measuring a pilot signal strength at each of said plurality of radio frequency antennas; and

link selection means, responsive to said determined pilot signal strengths, for activating said interconnect means to apply radio frequency signals to said selected ones of said aircraft radio frequency antennas with radio frequency signals to match said plurality of radio frequency characteristics of said corresponding multi-dimensional Radio Frequency sectors.

3. The system for managing radio frequency communications of claim 2 wherein said plurality of Air-To-Ground terrestrial base stations comprises:

sector generation means for generating a pattern of radio frequency signals that divides said multi-dimensional space into multi-dimensional Radio Frequency sectors in one of azimuth, elevation, altitude, and multiple planes.

4. The system for managing radio frequency communications of claim 3 wherein said plurality of radio frequency characteristics are selected from the set of characteristics that include:

Time, Space, Code, Polarization, Antenna-Aircraft, Antenna-Ground, Frequency, Azimuth Sectoring, Elevation Sectoring, Pitch, Roll, Yaw, and Flight Speed.

5. The system for managing radio frequency communications of claim 1 wherein said plurality of Air-To-Ground terrestrial base stations comprises:

sector generation means for generating a pattern of radio frequency signals that divides said multi-dimensional space into multi-dimensional Radio Frequency sectors in one of azimuth, elevation, altitude, and multiple planes.

6. The system for managing radio frequency communications of claim 1 wherein said interconnect means comprises:

logical path linking means for transmitting a first part of said call traffic on a first of said multiple Air-To-Ground Radio Frequency communications links and a second part of said call traffic on a second of said multiple Air-To-Ground Radio Frequency communications links, wherein individual data packets in said call traffic are not time synchronous.

7. The system for managing radio frequency communications of claim 1 wherein said connection management means comprises:

pilot signal determining means, located in each of said aircraft, for measuring a pilot signal strength at each of said plurality of radio frequency antennas; and

primary link selection means, responsive to said determined pilot signal strengths, for selecting a primary one of said plurality of radio frequency antennas and associated polarization that corresponds to a strongest pilot signal strength.

8. The system for managing radio frequency communications of claim 7 wherein said connection management means further comprises:

secondary link selection means, responsive to said determined pilot signal strengths, for selecting a secondary one of said plurality of radio frequency antennas and associated polarization that corresponds to a second strongest pilot signal strength.

9. A method for managing radio frequency communications in a non-terrestrial region of space between a plurality of wireless subscriber devices located in each of a plurality of aircraft and a plurality of Air-To-Ground terrestrial base stations of an Air-To-Ground cellular communications network, comprising:

operating a plurality of radio frequency antennas mounted on the exterior surface of each of said aircraft;

selectively applying said radio frequency communication signals onto selected ones of said plurality of radio frequency antennas to simultaneously maintain multiple Air-To-Ground Radio Frequency communications links with selected ones of said plurality of Air-To-Ground terrestrial base stations of said Air-To-Ground cellular communications network;

populating, using a plurality of Air-To-Ground terrestrial base stations of said Air-To-Ground cellular communications network said non-terrestrial region of space with a plurality of multi-dimensional Radio Frequency sectors, each having a plurality of radio frequency characteristics, to exchange call traffic between said plurality of wireless subscriber devices and said Air-To-Ground cellular communications network; and

identifying a correspondence between selected ones of said aircraft radio frequency antennas and selected ones of said plurality of multi-dimensional Radio Frequency sectors to establish said Air-To-Ground Radio Frequency communications links.

10. The method for managing radio frequency communications of claim 9 wherein said step of identifying comprises:

measuring, in each of said aircraft, a pilot signal strength at each of said plurality of radio frequency antennas; and

activating, in response to said determined pilot signal strengths, said interconnect means to apply radio frequency signals to said selected ones of said aircraft radio frequency antennas with radio frequency signals to match said plurality of radio frequency characteristics of said corresponding multi-dimensional Radio Frequency sectors.

11. The method for managing radio frequency communications of claim 10 wherein said step of populating comprises:

generating a pattern of radio frequency signals that divides said multi-dimensional space into multi-dimensional Radio Frequency sectors in one of azimuth, elevation, altitude, and multiple planes.

12. The method for managing radio frequency communications of claim 11 wherein said plurality of radio frequency characteristics are selected from the set of characteristics that include:

Time, Space, Code, Polarization, Antenna-Aircraft, Antenna-Ground, Frequency, Azimuth Sectoring, Elevation Sectoring, Pitch, Roll, Yaw, and Flight Speed.

13. The method for managing radio frequency communications of claim 9 wherein said step of populating comprises:

generating a pattern of radio frequency signals that divides said multi-dimensional space into multi-dimensional Radio Frequency sectors in one of azimuth, elevation, altitude, and multiple planes.

14. The method for managing radio frequency communications of claim 9 wherein said step of identifying comprises:

transmitting a first part of said call traffic on a first of said multiple Air-To-Ground Radio Frequency communications links and a second part of said call traffic on a second of said multiple Air-To-Ground Radio Frequency communications links, wherein individual data packets in said call traffic are not time synchronous.

15. The method for managing radio frequency communications of claim 9 wherein said step of identifying comprises:

measuring, in each of said aircraft, a pilot signal strength at each of said plurality of radio frequency antennas; and

selecting, in response to said determined pilot signal strengths, a primary one of said plurality of radio frequency antennas and associated polazation that corresponds to a strongest pilot signal strength.

16. The method for managing radio frequency communications of claim 15 wherein said step of identifying further comprises:

selecting, in response to said determined pilot signal strengths, a secondary one of said plurality of radio frequency antennas and associated polarization that corresponds to a second strongest pilot signal strength.