Array antenna calibration apparatus and method

• US 20060273959A1
• Filed: 08/24/2005
• Published: 12/07/2006
• Est. Priority Date: 05/19/2005
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Kawasaki, Toshio
• Granted Patent: US 7,545,321 B2
• Time in Patent Office: Days
• US Class Current: 342/368
• CPC Class Codes: H01Q 3/267 Phased-array testing or checking devices

Abstract

The apparatus comprises a calibration signal supply means, which supplies calibration signals to a plurality of antenna elements that are to be subjected to calibration; a calibration signal extracting means, which extracts the calibration signals from signals received by the antenna elements placed, one on each side of the plurality of antenna elements that are to be subjected to calibration, and a calibration control means and which individually controls the phases of signals to be transmitted from the plurality of antenna elements that are to be subjected to calibration, based on the phase differences among the calibration signals extracted by the calibration signal extracting means. This will realize accurate calibration of an array antenna, irrespective of antenna element interval deviation.

Claims

1. An array antenna calibration apparatus for calibrating an array antenna having multiple antenna elements, said apparatus comprising:

calibration signal supply means which supplies calibration signals to a plurality of antenna elements that are to be subjected to calibration;

calibration signal extracting means which extracts the calibration signals from signals received by the antenna elements placed, one on each side of the plurality of antenna elements that are to be subjected to calibration, and

calibration control means which individually controls the phases of signals to be transmitted from the plurality of antenna elements that are to be subjected to calibration, based on the phase differences among the calibration signals extracted by said calibration signal extracting means.

2. An array antenna calibration apparatus as set forth in claim 1, wherein said calibration signal extracting means includes:

a switch unit which selectively outputs signals received by the antenna elements placed, one on each side of the plurality of antenna elements that are to be subjected

a radio receiver unit which receives an output signal of said switch unit; and

a calibration signal detecting unit which detects the calibration signal from the signal received by said radio receiver unit.

3. An array antenna calibration apparatus as set forth in claim 1, wherein said calibration signal detecting means includes:

a plurality of radio receiver units provided, one for each of the antenna elements that are placed, one on each side of the plurality of antenna elements that are to be subjected to calibration, said plurality of radio receiver units receiving signals which are received by the antenna elements placed, one on each side of the plurality of antenna elements; and

a plurality of calibration signal detecting units, provided one for each of said plurality of radio receiver units, for detecting the calibration signal from the signal received by each of said plurality of radio receiver units.

4. An array antenna calibration apparatus as set forth in claim 1, wherein said calibration signal detecting means detects the calibration signal from a signal received by each of said plurality of antenna elements that are to be subjected to calibration.

5. An array antenna calibration apparatus as set forth in claim 2, wherein said calibration signal detecting means detects the calibration signal from a signal received by each of said plurality of antenna elements that are to be subjected to calibration.

6. An array antenna calibration apparatus as set forth in claim 3, wherein said calibration signal detecting means detects the calibration signal from a signal received by each of said plurality of antenna elements that are to be subjected to calibration.

7. An array antenna calibration apparatus as set forth in claim 1, wherein the antenna elements placed, one on each side of the plurality of antenna elements that are to be subjected to calibration are dummy antenna elements.

8. An array antenna calibration method as set forth in claim 1, wherein any of time-division multiplexed signals, code-division multiplexed signals, and frequency-division multiplexed signals are supplied as the calibration signals.

9. An array antenna calibration apparatus for calibrating an array antenna having multiple antenna elements, said apparatus comprising:

calibration signal supply means which supplies calibration signals to a plurality of antenna elements placed, one on each side of a plurality of antenna elements that are to be subjected to calibration;

calibration signal detecting means which detects the calibration signals from signals received by the plurality of antenna elements that are to be subjected to calibration; and

calibration control means which individually controls the phases of the signals received by the plurality of antenna elements that are to be subjected to calibration, based on the phase differences among the calibration signals detected by said calibration signal detecting means.

10. An array antenna calibration apparatus as set forth in claim 9, wherein said calibration signal supply means includes:

a calibration signal generating unit which generates the calibration signals;

a radio transmitter unit which sends the calibration signals, which are generated by said calibration signal generating unit, as radio signals;

a switch unit which selectively outputs the radio signals from said radio transmitter unit to antenna elements placed, one on each side of the plurality of antenna elements that are to be subjected to calibration.

11. An array antenna calibration apparatus as set forth in claim 9, wherein said calibration signal supply means includes:

a calibration signal generating unit which generates the calibration signals;

a plurality of radio transmitter units provided, one for each of the antenna elements that are placed, one on each side of the plurality of antenna elements that are to be subjected to calibration, said plurality of radio transmitter units sending the calibration signals, which are generated by said calibration signal generating unit, as radio signals.

12. An array antenna calibration apparatus as set forth in claim 9, wherein the antenna elements placed, one on each side of the plurality of antenna elements that are to be subjected to calibration are dummy antenna elements.

13. An array antenna calibration apparatus as set forth in claim 9, wherein said calibration signal supply means supplies any of time-division multiplexed signals, code-division multiplexed signals, and frequency-division multiplexed signals.

14. An array antenna calibration method for calibrating an array antenna having multiple antenna elements, said method comprising:

emitting calibration signals from a plurality of antenna elements that are to be subjected to calibration;

detecting the calibration signals from signals received by antenna elements that are placed, one on each side of the plurality of antenna elements that are to be subjected to calibration; and

controlling individually the phases of signals to be sent from the plurality of antenna elements based on the phase differences among the detected calibration signals.

15. An array antenna calibration method as set forth in claim 14, wherein the antenna elements placed, one on each side of the plurality of antenna elements that are to be subjected to calibration are dummy antenna elements.

16. An array antenna calibration method as set forth in claim 14, wherein any of time-division multiplexed signals, code-division multiplexed signals, and frequency-division multiplexed signals are supplied as the calibration signals.

17. An array antenna calibration method for calibrating an array antenna having multiple antenna elements, said method comprising:

emitting calibration signals from antenna elements placed, one on each side of a plurality of antenna elements that are to be subjected to calibration;

detecting the calibration signals from signals received by the plurality of antenna elements; and

controlling individually the phases of the signals received by the plurality of antenna elements based on the phase differences among the detected calibration signals.

18. An array antenna calibration method as set forth in claim 17, wherein the antenna elements placed, one on each side of the plurality of antenna elements that are to be subjected to calibration are dummy antenna elements.

19. An array antenna calibration method as set forth in claim 17, wherein any of time-division multiplexed signals, code-division multiplexed signals, and frequency-division multiplexed signals are supplied as the calibration signals.