Calibration of a Transmitter with Internal Power Measurement

• US 20120250534A1
• Filed: 03/30/2011
• Published: 10/04/2012
• Est. Priority Date: 03/30/2011
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Infineon Technologies AG
• Inventors: Langer, Andreas, Bruder, Thomas
• Granted Patent: US 9,379,826 B2
• Time in Patent Office: Days
• US Class Current: 370/252
• CPC Class Codes: H04B 17/11 for calibration
• CPC Class Codes: H04B 17/13 of power amplifiers, e.g. gain or non-linearity
• CPC Class Codes: H04B 17/19 Self-testing arrangements

Abstract

A method for calibrating a transmitter includes operating the transmitter using a first transmitter setting; obtaining, via an external reference measuring device, a transmit power reference value indicative of a first transmit power of the transmitter corresponding to the first transmitter setting, and obtaining, using an internal measuring device of the transmitter or of a receiver associated with the transmitter, a first uncalibrated transmit power measurement value corresponding to the first transmit power. The method further includes calibrating the internal measuring device using the transmit power reference value and the first uncalibrated transmit power measurement value to provide a calibrated internal measuring device, operating the transmitter using a second transmitter setting, and obtaining, using the calibrated internal measuring device, a second transmit power measurement value indicative of a second transmit power corresponding to the second transmitter setting. Lastly, the method includes obtaining self-calibration data based on the second transmitter setting and the second transmit power measurement value, and storing the self-calibration data in a calibration data structure.

Claims

1. A method for calibrating a transmitter, the method comprising:

operating the transmitter using a first transmitter setting;

obtaining, via an external reference measuring device, a transmit power reference value indicative of a first transmit power of the transmitter corresponding to the first transmitter setting;

obtaining, using an internal measuring device of the transmitter or using a receiver associated with the transmitter, a first uncalibrated transmit power measurement value corresponding to the first transmit power;

calibrating the internal measuring device using the transmit power reference value and the first uncalibrated transmit power measurement value to provide a calibrated internal measuring device;

operating the transmitter using a second transmitter setting;

obtaining, using the calibrated internal measuring device, a second transmit power measurement value indicative of a second transmit power corresponding to the second transmitter setting;

obtaining self-calibration data based on the second transmitter setting and the second transmit power measurement value; and

storing the self-calibration data in a calibration data structure.

2. The method according to claim 1, further comprising:

receiving a command at the transmitter instructing the transmitter to perform the action of operating the transmitter using the second transmitter setting, of obtaining the second transmit power measurement value, and of obtaining and storing the self-calibration data.

3. The method according to claim 1, wherein the second transmitter setting is a self-calibration transmitter setting,

wherein the second transmit power measurement value is a self-calibration transmit power measurement value,

wherein the actions of operating the transmitter and of obtaining a transmit power measurement value are repeated for a plurality of self-calibration transmitter settings, and

wherein the self-calibration data are obtained based on the plurality of self-calibration transmitter settings and the self-calibration transmit power measurement values obtained for the plurality of self-calibration transmitter settings.

4. The method according to claim 3, further comprising:

evaluating a list indicative of the plurality of self-calibration transmitter settings.

5. The method according to claim 4, wherein the list specifies at least one of a mode, a frequency, and a bias condition for the plurality of self-calibration transmitter settings.

6. The method according to claim 1, wherein the actions of operating the transmitter using the first transmitter setting, obtaining the transmit power reference value, and obtaining the transmit power measurement value are repeated a plurality of times for a plurality of external calibration transmitter settings, wherein the method further comprises:

storing a plurality of measurement calibration points each being based on a transmit power reference value and a corresponding uncalibrated transmit power measurement value; and

wherein the action of obtaining the second transmit power measurement value comprises selecting a calibration point of the plurality of measurement calibration points as a support calibration point for the calibrated internal measuring device in order to take into account a local calibration of the internal measuring device in the vicinity of the selected calibration point.

7. The method according to claim 1, further comprising:

calculating a correction factor for the transmitter setting based on the self-calibration data and the self-calibration transmitter setting.

8. The method according to claim 7, further comprising:

extrapolating the correction factor to a range of transmitter settings exterior to a measurement range of the internal measuring device.

9. The method according to claim 1, wherein the actions of operating the transmitter using the second transmitter setting and obtaining the second transmit power measurement value are performed in a time span having a duration that is shorter than a duration of a time slot used during normal operation of the transmitter.

10. The method according to claim 9, wherein the time span is determined by a time required to take a data point comprising the second transmitter setting and the second transmit power measurement value.

11. The method according to claim 9, wherein a duration of a reduced time slot, during which the actions of operating the transmitter using the second transmitter setting and obtaining the second transmit power measurement value are performed, has a duration between 100 μ

s and 300 μ

s.

12. The method according to claim 1, wherein the actions of obtaining the transmit power reference value and obtaining the first uncalibrated transmit power measurement value are performed while the transmitter is being operated using a first set of parameters defined by a specification of a first wireless communication standard;

and

wherein the action of obtaining the second transmit power measurement value and storing calibration data based on the second transmitter setting and the second transmit power measurement value are performed while the transmitter is being operated using a second set of parameters defined by a specification of a second wireless communications standard;

wherein the first wireless communications standard differs from the second wireless communications standard with respect to at least one of;

carrier frequencies, number of available carrier frequencies, power range, power envelope, spectral mask, and type of modulation.

13. The method according to claim 1, further comprising:

using the external reference measuring device to perform a calibration procedure of another transmitter concurrently with performing at least one of the actions of operating the transmitter using the second transmitter setting, obtaining the second transmit power measurement value, and storing the self-calibration data.

14. The method according to claim 1, further comprising:

connecting the external measuring device with the transmitter prior to the action of obtaining the first transmit power reference value;

disconnecting the external measuring device from the transmitter after one or more execution of the action of obtaining the first transmit power reference value; and

connecting the external measuring device with another transmitter to perform the action of obtaining the other transmitter'"'"'s first transmit power reference value.

15. A computer program stored on a non-transitory storage medium having a program code for performing when running on a computer, a method for calibrating a transmitter, the method comprising:

configuring the transmitter to operate using a first transmitter setting;

obtaining, via an external reference measuring device, a transmit power reference value indicative of a first transmit power of the transmitter corresponding to the first transmitter setting;

obtaining, using an internal measuring device of the transmitter or using a receiver associated with the transmitter, a first uncalibrated transmit power measurement value corresponding to the first transmit power;

calibrating the internal measuring device using the transmit power reference value and the first uncalibrated transmit power measurement value to provide a calibrated internal measuring device;

configuring the transmitter to operate using a second transmitter setting;

obtaining, using the calibrated internal measuring device, a second transmit power measurement value indicative of a second transmit power corresponding to the second transmitter setting; and

obtaining self-calibration data based on the second transmitter setting and the second transmit power measurement value; and

storing the self-calibration data in a calibration data structure.

16. A method for calibrating a transmitter, the method comprising:

operating the transmitter using a first transmitter setting;

obtaining, via an external reference measuring device, a transmit power reference value indicative of a first transmit power corresponding to the first transmitter setting;

obtaining, using an internal measuring device of the transmitter or using a receiver associated with the transmitter, a first uncalibrated transmit power measurement value corresponding to the first transmit power;

calibrating the internal measuring device using the transmit power reference value and the first uncalibrated transmit power measurement value to provide a calibrated internal measuring device;

receiving a command at the transmitter instructing the transmitter to successively operate the transmitter using a plurality of self-calibration transmitter settings;

successively obtaining, using the calibrated internal measuring device, a plurality of self-calibration transmit power measurement values indicative of a plurality of self-calibration transmit powers corresponding to the plurality of self-calibration transmitter settings, respectively; and

obtaining calibration data based on the plurality of self-calibration transmitter settings and the plurality of self-calibration transmit power measurement values and storing the self-calibration data in a calibration data structure.

17. A transmitter comprising

a transmit chain;

an internal measuring device configured to measure a transmit power to obtain a transmit power measurement value indicative of a transmit power of the transmitter;

a transmitter setting component configured to provide at least two transmitter settings to the transmit chain;

a calibrator component configured to;

receive, from an external reference measuring device, a transmit power reference value indicative of a transmit power of the transmitter corresponding to a first one of the at least two transmitter settings;

receive a first uncalibrated transmit power measurement value from the internal measuring device corresponding to the transmit power of the transmitter;

calibrate the internal measuring device using the transmit power reference value and the first uncalibrated transmit power measurement value;

cause the transmitter setting component to select a second transmitter setting of the at least two transmitter settings;

obtain a second transmit power measurement value from the calibrated internal measuring device; and

determine self-calibration data for the transmitter setting component based on the second transmitter setting and the second transmit power measurement value.

18. The transmitter according to claim 17, further comprising a command interface configured to receive a command instructing the transmitter to operate the transmitter in the second transmitter setting and obtain the second transmit power measurement value from the internal measuring device.

19. The transmitter according to claim 17, wherein the calibrator component is further configured to cause the transmitter setting component to successively select a plurality of self-calibration transmitter settings, operate the transmitter according to the plurality of self-calibration transmitter settings, and obtain a plurality of self-calibration transmit power measurement values corresponding to the plurality of self-calibration transmitter settings from the internal measuring device.

20. The transmitter according to claim 19, wherein the calibrator component is further configured to evaluate a list specifying a plurality of self-calibration settings, wherein the list specifies at least one of a mode, a frequency, and a bias condition for each one of the plurality of self-calibration settings.

21. The transmitter according to claim 17, wherein the calibrator component is configured to operate the transmitter using the second transmitter setting and obtain the second transmit power measurement value in a time span having a duration that is shorter than a duration of a time slot used during normal operation of the transmitter.

22. A calibration arrangement comprising a transmitter in combination with a reference measuring device that is external to the transmitter, the transmitter comprising:

a transmit chain;

an internal measuring device configured to measure a transmit power to obtain a transmit power measurement value indicative of a transmit power of the transmitter;

a transmitter setting component configured to provide at least two transmitter settings to the transmit chain;

a calibrator component configured to;

receive a transmit power reference value from the reference measuring device indicative of a transmit power of the transmitter corresponding to a first one of the at least two transmitter settings,

receive a first uncalibrated transmit power measurement value from the internal measuring device corresponding to the transmit power of the transmitter;

calibrate the internal measuring device using the transmit power reference value and the first uncalibrated transmit power measurement value;

cause the transmitter setting component to select a second transmitter setting of the at least two transmitter settings;

obtain a second transmit power measurement value from the calibrated internal measuring device; and

calculate self-calibration data for the transmitter setting component based on the second transmitter setting and the second transmit power measurement value.

23. A calibration arrangement, comprising:

means for providing a transmit signal;

means for measuring a transmit power of the transmit signal;

means for controlling the transmitting means to transmit the transmit signal using a transmitter setting selected from at least two transmitter settings;

means for calibrating the measuring means to obtain a calibrated measuring means, the calibrating means being configured to receive a transmit power reference value from an external reference measuring device and a corresponding first uncalibrated transmit power measurement value from the measuring means, and also configured to calibrate the measuring means based on the received transmit power reference value and the received first uncalibrated transmit power measurement value;

means for performing an autonomous calibration procedure configured to set the controlling means to operate the transmitting means using another transmitter setting selected from the at least two transmitter settings, to obtain a second transmit power measurement value from the calibrated means for measuring, and calibrate the trans-mitting means based on the other transmitter setting and the second transmit power measurement value.

24. The calibration arrangement according to claim 23, further comprising a means for storing calibration data, the calibration data being based on the other transmitter setting and the second transmit power measurement value.