Claims
- 1. A method for calibrating an antenna array that transmits communication traffic signals during beamforming in a mobile radio communication system, said antenna array comprising a number of transmitting antenna sections each comprising transmitting components that might distort the phase and the amplitude of signals that are to be transmitted, said method comprising the steps of:a) generating a single calibration signal; b) injecting said calibration signal into each transmitting antenna section, one at a time; c) collecting a resulting calibration signal from each transmitting antenna section after having passed the transmitting components in each transmitting antenna section, one at a time; d) generating correction factors for each transmitting antenna section; and e) adjusting said transmitting antenna sections with said correction factors, wherein said steps are performed during a limited amount of time on a traffic channel in use.
- 2. A method for calibrating an antenna array according to claim 1, where in said generation of correction factors comprises:a) selecting one of the transmitting antenna sections as a reference section; b) determining a correction factor for the reference section; and c) generating correction factors for the rest of the transmitting antenna sections, one at a time, relative the correction factor of the reference section.
- 3. A method for calibrating an antenna array according to claim 1, wherein said calibration signal has a positive phase slope during a first time interval and a negative phase slope during a second consecutive time interval, and wherein the calibration signal is sampled in the first and the second time interval, and wherein samples from the first time interval are compared with samples from the second time interval, in order to estimate a time error.
- 4. A method for calibrating an antenna array according to claim 1, wherein said calibration signal is a pure sinusoid.
- 5. A method for calibrating an antenna array according to claim 1, wherein said generation of correction factors for each transmitting antenna section comprises the steps of:a) modeling the received signals as complex data samples; and b) generating said correction factors as complex factors.
- 6. A method for calibrating an antenna array according to claim 1, wherein said correction factors compensate for signal errors introduced by the transmitting components in each transmitting antenna section, and for signal errors introduced by means used for calibrating the antenna array.
- 7. A method for calibrating an antenna array according to claim 1, wherein said correction factors are limiting the signal power of transmitted signals.
- 8. A method for calibrating an antenna array according to claim 1, wherein said correction factors adjust the phase of the signals that are to be transmitted by the antenna sections.
- 9. A method for calibrating an antenna array according to claim 1, wherein said correction factors adjust the amplitude of signals that are to be transmitted by the antenna sections.
- 10. A method for calibrating an antenna array according to claim 1, wherein said correction factors adjust the phase and amplitude of signals that are to be transmitted by the antenna sections.
- 11. A method for calibrating an antenna array according to claim 1, wherein the correction factors are applied to signals that are to be transmitted, after active beamforming.
- 12. A method for calibrating an antenna array according to claim 1, wherein the calibration signal is a lower-power spread spectrum signal that is injected into the normal traffic flow.
- 13. A method for calibrating an antenna array according to claim 1, wherein the radio communication system is a CDMA-system with a predetermined number of codes that are allowed for use during normal traffic, wherein a code that is not intended to be used for traffic is used for calibration.
- 14. A method for calibrating an antenna array according to claim 1, wherein said method is continuously repeated.
- 15. A method for calibrating an antenna array according to claim 1, wherein said method is repeated at certain time intervals.
- 16. A method for calibrating an antenna array that transmits communication traffic signals during beamforming in a mobile radio communication system, said antenna array comprising a plurality of transmitting antenna sections each comprising transmitting components that might distort the phase and the amplitude of signals that are to be transmitted, said method comprising the steps of:a) generating a set of orthogonal calibration signals; b) injecting said calibration signal into the respective transmitting antenna sections, in parallel; c) collecting a respective resulting calibration signal from each transmitting antenna section after having passed the transmitting components in the respective transmitting antenna sections; d) generating correction factors for each transmitting antenna section; and e) adjusting said transmitting antenna sections with said correction factors, wherein said steps are performed during a limited amount of time on a traffic channel in use.
- 17. A method for calibrating an antenna array according to claim 16, wherein the calibration signals are of different frequencies.
- 18. A method for calibrating an antenna array according to claim 16, wherein the calibration signals are different orthogonal codes.
- 19. A method for calibrating an antenna array according to claim 16, wherein said calibration signal is a pure sinusoid.
- 20. A method for calibrating an antenna array according to claim 16, wherein said generation of correction factors for each transmitting antenna section comprises the steps of:a) modeling the received signals as complex data samples; and b) generating said correction factors as complex factors.
- 21. A method for calibrating an antenna array according to claim 16, wherein said correction factors compensate for signal errors introduced by the transmitting components in each transmitting antenna section, and for signal errors introduced by means used for calibrating the transmission of the antenna array.
- 22. A method for calibrating an antenna array according to claim 16, wherein said correction factors are limiting the signal power of transmitted signals.
- 23. A method for calibrating an antenna array according to claim 16, wherein said correction factors adjust the phase of the signals that are to be transmitted by the antenna sections.
- 24. A method for calibrating an antenna array according to claim 16, wherein said correction factors adjust the amplitude of signals that are to be transmitted by the antenna sections.
- 25. A method for calibrating an antenna array according to claim 16, wherein said correction factors adjust the phase and amplitude of signals that are to be transmitted by the antenna sections.
- 26. A method for calibrating an antenna array according to claim 16, wherein the correction factors are applied to signals that are to be transmitted, after active beamforming.
- 27. A method for calibrating an antenna array according to claim 16, wherein the calibration signal is a low-power spread spectrum signal that is injected into the normal traffic flow.
- 28. A method for calibrating an antenna array according to claim 16, wherein the radio communication system is a CDMA-system with a predetermined number of codes that are allowed for use during normal traffic, wherein a code that is not intended to be used for traffic is used for calibration.
- 29. A system for calibrating an antenna array that transmits communication traffic signals during beamforming in a mobile radio communication system, said antenna array comprising a number of transmitting antenna sections each comprising transmitting components that might distort the phase and the amplitude of signals that are to be transmitted, said system comprising:means for generating a single calibration signal; means for injecting said calibration signal into each transmitting antenna section, one at a time; means for collecting a resulting calibration signal from each transmitting antenna section after having passed the transmitting components in each transmitting antenna section, one at a time; means for generating correction factors for each transmitting antenna section; and means for adjusting said transmitting antenna sections with said correction factors, wherein said method for calibrating is performed during a limited amount of time on a traffic channel in use.
- 30. A system for calibrating an antenna array according to claim 29, wherein said correction factors adjust the phase of signals that are to be transmitted by the antenna sections.
- 31. A system for calibrating an antenna array according to claim 29, wherein said correction factors adjust the amplitude of signals that are to be transmitted by the antenna sections.
- 32. A system for calibrating an antenna array according to claim 29, wherein said correction factors adjust the phase and amplitude of signals that are to be transmitted by the antenna sections.
- 33. A system for calibrating an antenna array according to claim 29, wherein the correction factors are applied to signals that are to be transmitted, after active beamforming.
- 34. A system for calibrating an antenna array that transmits communication traffic signals during beamforming in a mobile radio communication system, said antenna array comprising a plurality of transmitting antenna sections each comprising transmitting components that might distort the phase and the amplitude of signals that are to be transmitted, said system comprising:means for generating a set of orthogonal calibration signals; means for injecting said calibration signal into the respective transmitting antenna sections, in parallel; means for collecting a respective resulting calibration signal from each transmitting antenna section after having passed the transmitting components in the respective transmitting antenna sections; means for generating correction factors for each transmitting antenna section; and means for adjusting said transmitting antenna sections with said correction factors, wherein said system for calibrating is performed during a limited amount of time on a traffic channel in use.
- 35. A system for calibrating the transmission of an antenna array according to claim 34, wherein said correction factors adjust the phase of signals that are to be transmitted by the antenna sections.
- 36. A system for calibrating the transmission of an antenna array according to claim 34, wherein said correction factors adjust the amplitude of signals that are to be transmitted by the antenna sections.
- 37. A system for calibrating the transmission of an antenna array according to claim 34, wherein said correction factors adjust the phase and amplitude of signals that are to be transmitted by the antenna sections.
- 38. A system for calibrating the transmission of an antenna array according to claim 34, wherein the correction factors are applied to signals that are to be transmitted, after active beamforming.
FIELD OF THE INVENTION
This application is a divisional of application Ser. No. 08/844,638 now U.S. Pat. No. 6,157,343, filed Apr. 21, 1997.
This application is a continuation in part of U.S. Ser. No. 08/709,877 now abandoned filed Sep. 9, 1996 on of U.S. Ser. No. 08/253,295 now abandoned filed Jun. 3, 1994. The present invention relates to an antenna array for use in a base station in a cellular communication system. More particularly the present invention relates to a method and apparatus for calibrating an antenna array that receives and transmits communication signals without disturbing the normal traffic in the cellular communication system.
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Continuations (1)
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Number |
Date |
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Parent |
08/253295 |
Jun 1994 |
US |
Child |
08/709877 |
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US |
Continuation in Parts (1)
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Number |
Date |
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Parent |
08/709877 |
Sep 1996 |
US |
Child |
08/844638 |
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US |