Dynamic antenna platform offset calibration

Patent metadata

Field	Value
Publication number	US-10446906-B2
Application number	US-201816229470-A
Country	US
Kind code	B2
Filing date	Dec 21, 2018
Priority date	Jul 6, 2017
Publication date	Oct 15, 2019
Grant date	Oct 15, 2019

Abstract

Systems and methods are described for supporting dynamic antenna platform offset calibration for an antenna system mounted to a mobile vehicle. In particular, dynamic antenna platform offset calibration can be performed while communicating user data associated with the mobile vehicle (e.g., based at least in part on alignment calibration procedures including measurements of user data signals), with an antenna platform offset being updated when alignment calibration procedures have been performed at suitably separated spatial conditions. Accordingly, antenna platform offset calibration may be performed throughout the operation of the mobile vehicle without requiring that the vehicle be proactively aligned in a particular orientation for a dedicated calibration routine prior to using the antenna for communicating user data during normal operation of the mobile vehicle.

First claim

What is claimed is:

1. A method, comprising:
communicating, via a beam of an antenna, first user data with a target device;
performing a plurality of alignment calibration procedures to determine respective peaked pointing directions from the antenna to the target device based at least in part on a measured signal characteristic associated with the communicating during the respective alignment calibration procedure;
determining that a set of the plurality of alignment calibration procedures has been performed at respective spatial conditions that satisfy a spatial separation criteria;
determining an antenna platform offset between a first reference frame of the antenna and a second reference frame that is external to the antenna based at least in part on the peaked pointing directions determined for each of the set of the plurality of alignment calibration procedures; and
communicating, via the beam of the antenna, second user data with the target device based at least in part on the determined antenna platform offset.

2. The method of claim 1 , further comprising:
determining, for each of the set of the plurality of alignment calibration procedures, a respective antenna pointing offset based at least in part on a difference between an estimated pointing direction from the antenna to the target device and the respective peaked pointing direction, wherein determining the antenna platform offset is based at least in part on the determined antenna pointing offsets.

3. The method of claim 2 , further comprising:
determining, for each of the set of the plurality of alignment calibration procedures, a relative location of the target device from the antenna, wherein the estimated pointing direction is determined based at least in part on the relative location.

4. The method of claim 1 , wherein performing the plurality of alignment calibration procedures comprises performing a first alignment calibration procedure having a spatial condition in a spatial condition range and performing a second alignment calibration procedure having a spatial condition in the spatial condition range, the method further comprising:
selecting one of the first alignment calibration procedure or the second alignment calibration procedure for the set of the plurality of alignment calibration procedures based at least in part on a fitness metric of the first alignment calibration procedure and a fitness metric of the second alignment calibration procedure.

5. The method of claim 4 , wherein the fitness metric comprises a relationship between a respective spatial condition and a nominal direction of the spatial condition range.

6. The method of claim 1 , wherein communicating the first user data is based at least in part on a zero antenna platform offset, a null antenna platform offset, or a manual antenna platform offset.

7. The method of claim 1 , wherein communicating the first user data is performed without an antenna platform offset being previously determined from peaked pointing directions.

8. The method of claim 1 , wherein communicating the first user data is performed with an antenna platform offset that was previously determined from peaked pointing directions.

9. The method of claim 1 , wherein the second reference frame is associated with an inertial sensor.

10. The method of claim 1 , wherein the second reference frame is associated with a vehicle.

11. The method of claim 1 , wherein the measured signal characteristics are based at least in part on user data signals.

12. The method of claim 1 , wherein performing the plurality of alignment calibration procedures is based at least in part on a requested data rate associated with the first user data.

13. The method of claim 1 , wherein determining the antenna platform offset is based at least in part on satisfying an offset calibration quality criteria.

14. The method of claim 13 , wherein the offset calibration quality criteria comprises a calculated matrix condition number for the antenna platform offset being below a threshold matrix condition number, or residuals associated with the antenna platform offset for each of the set of the plurality of alignment calibration procedures being below a threshold.

15. The method of claim 1 , wherein determining the antenna platform offset is based at least in part on an angular rate of pointing for the beam of the antenna being below a threshold, a residual error being below a threshold, a servo error being below a threshold, or a combination thereof.

16. The method of claim 1 , wherein determining that the set of the plurality of alignment calibration procedures has been performed at respective spatial conditions that satisfy the spatial separation criteria comprises:
determining that a number of angular ranges of antenna azimuth direction associated with the spatial conditions satisfies a threshold.

17. The method of claim 1 , wherein determining that the set of the plurality of alignment calibration procedures has been performed at respective spatial conditions that satisfy the spatial separation criteria comprises:
determining that a maximum angular separation between adjacent pairs of the spatial conditions is less than or equal to a threshold.

18. The method of claim 1 , wherein the target device for one of the plurality of alignment calibration procedures is different from the target device for another of the plurality of alignment calibration procedures.

19. An apparatus, comprising:
a processor;
memory in electronic communication with the processor; and
instructions stored in the memory and executable by the processor to cause the apparatus to:
communicate, via a beam of an antenna, first user data with a target device;
perform a plurality of alignment calibration procedures to determine respective peaked pointing directions from the antenna to the target device based at least in part on a measured signal characteristic associated with the communicating during the respective alignment calibration procedure;
determine that a set of the plurality of alignment calibration procedures has been performed at respective spatial conditions that satisfy a spatial separation criteria;
determine an antenna platform offset between a first reference frame of the antenna and a second reference frame that is external to the antenna based at least in part on the peaked pointing directions determined for each of the set of the plurality of alignment calibration procedures; and
communicate, via the beam of the antenna, second user data with the target device based at least in part on the determined antenna platform offset.

20. The apparatus of claim 19 , wherein the instructions to communicate the first user data are operable to perform the communicating without an antenna platform offset that is previously determined from peaked pointing directions.

21. The apparatus of claim 19 , wherein the instructions to communicate the first user data are operable to perform the communicating with an antenna platform offset that is previously determined from peaked pointing directions.

22. The apparatus of claim 19 , wherein the instructions are executable by the processor to cause the apparatus to determine the measured signal characteristics based at least in part on user data signals.

23. The apparatus of claim 19 , wherein the instructions to cause the apparatus to perform the plurality of alignment calibration procedures are based at least in part on a requested data rate associated

Assignees

• Viasat Inc

Inventors

• Merrell Douglas J

Classifications

• H01Q1/28

  Adaptation for use in or on aircraft, missiles, satellites, or balloons · CPC title

• H04B7/18545

  Arrangements for managing station mobility, i.e. for station registration or localisation · CPC title

• H01Q1/1257 Primary

  using the received signal strength · CPC title

• H01Q1/288

  Satellite antennas · CPC title

• H01Q1/42

  Housings not intimately mechanically associated with radiating elements, e.g. radome · CPC title