Airborne cell tower selection system and method

• US 8,547,277 B1
• Filed: 09/27/2010
• Issued: 10/01/2013
• Est. Priority Date: 09/27/2010
• Status: Active Grant

• Current Assignee: Rockwell Collins, Inc. (Raytheon Technologies Corporation d/b/a RTX)
• Original Assignee: Rockwell Collins, Inc. (Raytheon Technologies Corporation d/b/a RTX)
• Inventors: Mitchell, James P.
• Primary Examiner(s): LIU, HARRY K
• Application Number:
  US12/891,139
• Time in Patent Office: 1,100 Days
• Field of Search: 342/367
• US Class Current: 342/367
• CPC Class Codes: H04B 7/18506 Communications with or from aircraft, i.e. aeronautical mobile service
• CPC Class Codes: H04W 52/282 taking into account the speed of the mobile

Abstract

Disclosed are a system and method for controlling transmit power of a mobile node in air-to-ground communications to a fixed node. Power is controlled by taking into consideration the position of the mobile node, the ground position of a plurality of fixed nodes, and the RF pattern of an antenna. The ground position of the plurality of fixed nodes is determined by at least using a tower i.d. broadcast by the fixed nodes. Preferably, a power level is selected that will excite the fewest number of the plurality of fixed nodes while still maintaining a stable connection with at least one of the fixed nodes. The system may also utilize a repeater to receive communication signals from one or more mobile phones. This repeater then pre-amplifies the signal with a gain control signal received from one of the plurality of fixed nodes. The repeater would then pass the pre-amplified signal to the power amplifier for further amplification as controlled by the power controller.

Claims

1. A system for controlling transmit power of a mobile node in air-to-ground communications to a fixed node, the system comprising:

a first position determination unit configured to determine a position of the mobile node;

a second position determination unit configured to determine ground position information for a plurality of fixed nodes;

a receiver configured to receive a tower i.d.s from the plurality of fixed nodes;

a power amplifier configured to amplify the power of a communications signal; and

a power controller coupled to the power amplifier, the power amplifier configured to control a power level of the power amplifier, wherein power controller is configured to determine the power level according to the position of the mobile node, the ground position information of the plurality of fixed nodes, and the received tower i.d.s.

2. The system of claim 1, wherein the second position determination unit is configured to determine the ground position information for the plurality of fixed nodes which correspond to the received tower i.d.s.

3. The system of claim 1, wherein the second position determination unit is a database that stores the ground position information, and wherein the power controller is configured to utilize the ground position information from the database for the plurality of fixed nodes which correspond to the received tower i.d.s when determining the power level.

4. The system of claim 3, where in the database is configured to store an entry indicating the availability of each of the plurality of fixed nodes for air-to-ground communications, and wherein the power controller is further configured to utilize the ground position information from the database for the plurality of fixed nodes which correspond to the received tower i.d.s which have entries indicating a positive availability when determining the power level.

5. The system of claim 3 further comprising:

an antenna coupled to the power amplifier, the antenna being configured to produce an RF pattern when energized by the power amplifier, wherein the power controller is further configured to determine the power level based on the RF pattern.

6. The system of claim 5, further comprising a repeater coupled to the power amplifier, the repeater being configured to receive the communication signal from one or more communication devices and provide the communication signal to the power amplifier.

7. The system of claim 6, wherein the repeater is configured to pre-amplify the communication signal in accordance with a gain control signal received from one of the plurality of fixed nodes.

8. The system of claim 6, wherein the one or more communication devices. are mobile phones.

9. The system of claim 5, wherein the power controller is further configured to determine the power level that will cause the RF pattern to excite the fewest number of the plurality of fixed nodes while still maintaining a stable connection with at least one of the plurality of fixed nodes.

10. The system of claim 1, wherein the mobile node is located in or upon a vehicle, and wherein the power controller is further configured to determine the power level according to a heading of the vehicle.

11. The system of claim 1, wherein the mobile node is located in or upon an aircraft, and wherein the power controller is further configured to determine the power level according to at least one of a pitch, roll, and yaw of the aircraft.

12. The system of claim 1, wherein the first position determination unit includes a Global Positioning System (GPS) unit.

13. The system of claim 10, wherein the first position determination unit includes an Inertial Navigation System (INS) which provides the heading to the power controller.

14. The system of claim 5, wherein the antenna is a steerable antenna.

15. The system of claim 14, wherein the power controller is further configured to determine the power level according to a gain achieved by steering the steerable antenna toward at least one the plurality of fixed nodes.

16. The system of claim 5, wherein the antenna is a phased array antenna with an adjustable beam width.

17. The system of claim 16, wherein the power controller is further configured to determine the power level and a beam width of the phased array antenna that will cause the RF pattern to excite the fewest number of the plurality of fixed nodes while still maintaining a stable connection with at least one of the plurality of fixed nodes.

18. The system of claim 1, wherein the receiver receives the tower i.d.s from a secondary beam of the fixed node.

19. A method for controlling transmit power of a mobile node in air-to-ground communications to a fixed node, the mobile node including an antenna coupled to a power amplifier, the antenna being configured to produce an RF pattern when energized by the power amplifier, the method comprising the steps of:

determining a position of the mobile node;

receiving one or more tower i.d.s from a plurality of fixed nodes;

determining ground position information for the plurality of fixed nodes from which a corresponding tower i.d. was received; and

calculating a power level of the power amplifier utilizing the position of the mobile node, and the ground position information of the plurality of fixed nodes from which a corresponding tower i.d. was received.

20. The method of claim 19, wherein the calculating step further calculates the power level based on the RF pattern of the antenna.

21. The method of claim 20, wherein the calculating, step further calculates the power level that will cause the RF pattern to excite the fewest number of the plurality of fixed nodes while still maintaining a stable connection with at least one of the plurality of fixed nodes.

22. The method of claim 19, further comprising the step of:

checking a database for each tower i.d. received to determine if a corresponding fixed nodes is available,

wherein the determining ground position information step determines ground position information for the plurality of fixed nodes from which a corresponding tower i.d. was received and for which the checking step determined that the fixed node was available.