Systems and methods for remote L-band smart antenna distance measuring equipment diversity

• US 9,857,461 B2
• Filed: 10/14/2014
• Issued: 01/02/2018
• Est. Priority Date: 10/14/2013
• Status: Active Grant

• Current Assignee: Aviation Communication and Surveillance Systems LLC (L3Harris Technologies, Inc.)
• Original Assignee: Aviation Communication and Surveillance Systems LLC (L3Harris Technologies, Inc.)
• Inventors: Stayton, Gregory T.
• Primary Examiner(s): Sotomayor, John B
• Application Number:
  US14/514,145
• Publication Number:
  US 20150102953A1
• Time in Patent Office: 1,176 Days
• Field of Search: 342 47, 342 29- 40
• CPC Class Codes: G01S 13/785 Distance Measuring Equipment [DME] systems
• CPC Class Codes: G01S 7/42 Diversity systems specially adapted for radar
• CPC Class Codes: H01Q 1/28 Adaptation for use in or on aircraft, missiles, satellites, or balloons
• CPC Class Codes: H01Q 3/24 varying the orientation by switching energy from one active radiating element to another, e.g. for beam switching
• CPC Class Codes: H04B 1/3822 specially adapted for use in vehicles H04B1/3827 takes precedence
• CPC Class Codes: H04B 1/40 Circuits
• CPC Class Codes: H04B 7/0608 Antenna selection according to transmission parameters
• CPC Class Codes: H04B 7/0802 using antenna selection H04B7/0868 takes precedence; antenna beam directivity switching H01Q3/24

Abstract

Various avionics systems may benefit from the proper handling of diversity with respect to antennas. For example, systems and methods for remote L-band smart antenna distance measuring equipment may benefit from being prepared to provide diversity against interference, such as a multipath interference. A method can include determining which antenna of a plurality of antennas of an aircraft is preferred for communication with respect to distance measuring equipment. The method can also include selecting the antenna based on the determination.

Claims

1. A method, comprising:

determining, by a processor, which antenna of a plurality of antennas of an aircraft is preferred for communication with respect to distance measuring equipment, wherein a criterion of the determination is which antenna is expected quality of communication with the distance measuring equipment; and

selecting, by the processor, the antenna for communication with the distance measuring equipment based on the determination.

2. The method of claim 1, wherein a top antenna of the plurality of antennas is selected when a range to a distance measurement equipment ground station is greater than a predetermined threshold.

3. The method of claim 1, wherein a bottom antenna of the plurality of antennas is selected when a range to a distance measurement equipment ground station is less than a predetermined threshold.

4. The method of claim 1, wherein the determination is performed after identifying whether the aircraft is less than a predetermined threshold distance from a distance measurement equipment ground station.

5. The method of claim 1, wherein the determining comprises

transmitting a plurality of interrogations to establish a link from an aircraft interrogator to a replying ground transponder;

and

assessing quality of the replies to determine the antenna to be preferred for communication.

6. The method of claim 1, wherein the determining comprises comparing signal strength and/or signal reply time between or among antennas in order to select the antenna.

7. An apparatus, comprising:

at least one processor; and

at least one memory including computer program instructions,

wherein the at least one memory and the computer program instructions are configured to, with the at least one processor, cause the apparatus at least to

determine which antenna of a plurality of antennas of an aircraft is preferred for communication with respect to distance measuring equipment, wherein a criterion of the determination is which antenna is expected quality of communication with the distance measuring equipment; and

select the antenna for communication with the distance measuring equipment based on the determination.

8. The apparatus of claim 7, wherein the at least one memory and the computer program instructions are configured to, with the at least one processor, cause the apparatus at least to select a top antenna of the plurality of antennas when a range to a distance measurement equipment ground station is greater than a predetermined threshold.

9. The apparatus of claim 7, wherein the at least one memory and the computer program instructions are configured to, with the at least one processor, cause the apparatus at least to select a bottom antenna of the plurality of antennas when a range to a distance measurement equipment ground station is less than a predetermined threshold.

10. The apparatus of claim 7, wherein the at least one memory and the computer program instructions are configured to, with the at least one processor, cause the apparatus at least to perform the determination after identifying whether the aircraft is less than a predetermined threshold distance from a distance measurement equipment ground station.

11. The apparatus of claim 7, wherein the determination comprises

transmitting a plurality of interrogations to establish a link from an aircraft interrogator to a replying ground transponder;

and

assessing quality of the replies to determine the antenna to be preferred for communication.

12. The apparatus of claim 7, wherein the determination comprises comparing signal strength and/or signal reply time between or among antennas in order to select the antenna.

13. An apparatus, comprising:

means for determining which antenna of a plurality of antennas of an aircraft is preferred for communication with respect to distance measuring equipment, wherein a criterion of the determination is which antenna is expected quality of communication with the distance measuring equipment; and

means for selecting the antenna for communication with the distance measuring equipment based on the determination.

14. The apparatus of claim 13, wherein a top antenna of the plurality of antennas is selected when a range to a distance measurement equipment ground station is greater than a predetermined threshold.

15. The apparatus of claim 13, wherein a bottom antenna of the plurality of antennas is selected when a range to a distance measurement equipment ground station is less than a predetermined threshold.

16. The apparatus of claim 13, wherein the determination is performed after identifying whether the aircraft is less than a predetermined threshold distance from a distance measurement equipment ground station.

17. The apparatus of claim 13, wherein the means for determining comprises

means for transmitting a plurality of interrogations to establish a link from an aircraft interrogator to a replying ground transponder;

and

means for assessing quality of the replies to determine the antenna to be preferred for communication.

18. The apparatus of claim 13, wherein the means for determining comprises means for comparing signal strength and/or signal reply time between or among antennas in order to select the antenna.