Antenna array calibration for wireless communication systems

• US 20070099670A1
• Filed: 04/17/2006
• Published: 05/03/2007
• Est. Priority Date: 11/02/2005
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Vijayan, Rajiv, Gorokhov, Alexei, Naguib, Ayman
• Granted Patent: US 9,118,111 B2
• Time in Patent Office: Days
• US Class Current: 455/562.1
• CPC Class Codes: H01Q 3/267 Phased-array testing or checking devices
• CPC Class Codes: H04B 17/12 of transmit antennas, e.g. of the amplitude or phase
• CPC Class Codes: H04B 17/21 for calibration; for correcting measurements
• CPC Class Codes: H04B 17/24 with feedback of measurements to the transmitter

Abstract

Calibration for a transmit chain of a device transmitting information to multiple devices over wireless links includes selecting from between two or more calibration determination techniques. In certain aspects the techniques include phase only calibration and phase and amplitude calibration.

Claims

1. A method of calibrating an antenna array, comprising:

determining calibration weights for an antenna array based upon a first calibration technique;

determining calibration weights for an antenna array based upon a second calibration technique that is different calibration techniques; and

determining whether to apply the calibration weights from one of the first technique or the second technique.

2. The method of claim 1, wherein determining based upon the first calibration technique comprises determining based upon phase only information.

3. The method of claim 2, wherein determining based upon the second calibration technique comprises determining based upon phase and amplitude information.

4. The method of claim 2, wherein the phase only information comprises channel estimate information.

5. The method of claim 2, wherein the phase only information comprises a components of a calibration vector including both phase and amplitude information.

6. The method of claim 1, wherein determining comprises determining based upon a ratio of an output provided by the first calibration technique with respect to an output provided by the second calibration technique.

7. The method of claim 1, wherein determining comprises determining a difference between an amplitude mismatch between uncalibrated transmission and an output of the first calibration technique and uncalibrated transmission and an output of the second calibration technique.

8. The method of claim 1, wherein determining comprises determining a difference between a ratio of a difference between a minimum of an amplitude mismatch between uncalibrated transmission and an output of the first calibration technique and uncalibrated transmission and an output of the second calibration technique, and a maximum of an amplitude mismatch between uncalibrated transmission and an output of the first calibration technique and uncalibrated transmission and an output of the second calibration technique.

9. The method of claim 1, wherein determining based upon the first calibration technique and determining based upon the second calibration technique comprises determining based upon information only from a single access terminal.

10. The method of claim 1, wherein determining based upon the first calibration technique and determining based upon the second calibration technique comprises determining based upon information only from multiple access terminals.

11. The method of claim 1, wherein determining based upon the first calibration technique comprises determining based upon phase and amplitude information.

12. An wireless communication apparatus comprising:

at least two antennas; and

a processor coupled with the at least two antennas, the processor configured to determine a calibration type to apply, for communication with the two antennas, from at least two calibration types.

13. The wireless communication apparatus of claim 12, wherein one calibration type comprises calibration type comprises calibration based upon phase only information.

14. The wireless communication apparatus of claim 13, wherein another calibration type comprises calibration type comprises based upon phase and amplitude information.

15. The wireless communication apparatus of claim 12, wherein the processor is configured to determine the calibration type based upon a ratio of an output provided by a first calibration technique with respect to an output provided by a second calibration technique.

16. The wireless communication apparatus of claim 12, wherein the processor is configured to determine the calibration type based upon a difference between an amplitude mismatch between uncalibrated transmission and an output of a first calibration technique and uncalibrated transmission and an output of a second calibration technique.

17. The wireless communication apparatus of claim 12, wherein the processor is configured to determine the calibration type based upon a difference between a ratio of a difference between a minimum of an amplitude mismatch between uncalibrated transmission and an output of a first calibration technique and uncalibrated transmission and an output of a second calibration technique, and a maximum of an amplitude mismatch between uncalibrated transmission and an output of the first calibration technique and uncalibrated transmission and an output of the second calibration technique.

18. The wireless communication apparatus of claim 12, wherein the processor is configured to determine the calibration type based upon information only from a single access terminal.

19. The m wireless communication apparatus of claim 12, wherein the processor is configured to determine the calibration type based upon information only from multiple access terminals.

20. An apparatus for calibrating an antenna array, comprising:

means determining calibration weights for an antenna array based upon a first calibration technique;

means for determining calibration weights for an antenna array based upon a second calibration technique that is different calibration techniques; and

means for determining whether to apply the calibration weights from one of the first technique or the second technique.

21. The apparatus of claim 20, wherein the means for determining based upon the first calibration technique comprises means for determining based upon phase only information.

22. The apparatus of claim 21 wherein the means for determining based upon the second calibration technique comprises determining based upon phase and amplitude information.

23. The apparatus of claim 20, wherein the means for determining whether comprises means for determining based upon a ratio of an output provided by the first calibration technique with respect to an output provided by the second calibration technique.

24. The apparatus of claim 20, wherein the means for determining whether comprises means for determining a difference between an amplitude mismatch between uncalibrated transmission and an output of the first calibration technique and uncalibrated transmission and an output of the second calibration technique.

25. The apparatus of claim 20, wherein the means for determining whether comprises means for determining a difference between a ratio of a difference between a minimum of an amplitude mismatch between uncalibrated transmission and an output of the first calibration technique and uncalibrated transmission and an output of the second calibration technique, and a maximum of an amplitude mismatch between uncalibrated transmission and an output of the first calibration technique and uncalibrated transmission and an output of the second calibration technique.

26. The apparatus of claim 20, wherein the means for determining based upon the first calibration technique comprises means for determining based upon phase and amplitude information.

27. A processor readable instructions, stored on a processor readable media for causing a processor to:

determine calibration weights for an antenna array based upon a first calibration technique;

determine calibration weights for an antenna array based upon a second calibration technique that is different calibration techniques; and

determine whether to apply the calibration weights from one of the first technique or the second technique.