SYSTEM AND METHOD FOR DYNAMIC ADJUSTMENT OF CLOCK CALIBRATION

• US 20100317295A1
• Filed: 06/16/2009
• Published: 12/16/2010
• Est. Priority Date: 06/16/2009
• Status: Active Grant

• Current Assignee: Malikie Innovations Limited (Key Patent Innovations Limited)
• Original Assignee: Blackberry Limited
• Inventors: BORSELLA, Remo, SUNG, Alan
• Granted Patent: US 8,706,073 B2
• Time in Patent Office: Days
• US Class Current: 455/67.11
• CPC Class Codes: H04B 1/40 Circuits
• CPC Class Codes: H04B 17/11 for calibration

Abstract

A system for dynamically adjusting clock calibration in a wireless communication device. The system includes a temperature sensor for measuring a temperature, a primary clock coupled to the microprocessor for synchronizing the operation of the wireless communication device and a secondary clock coupled to the microprocessor for tracking time. A signal representing a measured temperature is received. At least one of a temperature measurement rate and a calibration rate based on the measured temperature is determined. A signal representing the at least one of the determined temperature measurement rate and the determined calibration rate is transmitted.

Claims

1. A system for dynamically adjusting clock calibration in a wireless communication device, the system comprising:

a microprocessor for controlling operation of the wireless communication device;

a temperature sensor for measuring a temperature;

a primary clock coupled to the microprocessor for synchronizing the operation of the wireless communication device;

a secondary clock coupled to the microprocessor for tracking time; and

a memory coupled to the microprocessor;

the memory including a dynamic adjustment module resident for execution by the microprocessor, the dynamic adjustment module being configured to;

receive a signal representing a measured temperature;

determine at least one of a temperature measurement rate and a calibration rate based on the measured temperature; and

transmit a signal representing the at least one of the determined temperature measurement rate and the determined calibration rate.

2. The system of claim 1 wherein the memory is further configured to:

receive a signal to bring the wireless communication device into a sleep mode;

determine whether calibration is current; and

if the calibration is not current, send a signal to wait for calibration to be current before entering sleep mode.

3. The system of claim 2 wherein the memory is configured to determine whether calibration is current by:

checking a stored indicator of whether the calibration is current.

4. The system of claim 1 wherein the memory is further configured to:

calibrate the secondary clock at the determined calibration rate; and

request a temperature measurement at the determined temperature measurement rate.

5. The system of claim 4 wherein the secondary clock is calibrated against the primary clock.

6. The system of claim 4 wherein the wireless communication device is preset with an initial temperature measurement rate and an initial calibration rate, and the memory is further configured to carry out a first instance of calibration according to the initial calibration rate and to request a first instance of temperature measurement according to the initial temperature measurement rate.

7. The system of claim 1 wherein, for determining at least one of the temperature measurement rate and the calibration rate, the memory is further configured to:

retrieve the at least one of the temperature measurement rate and the calibration rate from a look-up table using the measured temperature.

8. A method for dynamically adjusting clock calibration in a wireless communication device having a temperature sensor and a real time clock, the method comprising:

receiving a signal representing a measured temperature;

determining at least one of a temperature measurement rate and a calibration rate based on the measured temperature; and

transmitting a signal representing the at least one of the determined temperature measurement rate and the determined calibration rate.

9. The method of claim 8 wherein further comprising:

receiving a signal to bring the wireless communication device into a sleep mode;

determining whether calibration is current; and

if the calibration is not current, sending a signal to wait for calibration to be current before entering sleep mode.

10. The method of claim 9 wherein determining whether calibration is current comprises:

checking a stored indicator of whether the calibration is current.

11. The method of claim 8 further comprising:

calibrating the secondary clock at the determined calibration rate; and

requesting a temperature measurement at the determined temperature measurement rate.

12. The method of claim 11 wherein the secondary clock is calibrated against the primary clock.

13. The method of claim 11 wherein the wireless communication device is preset with an initial temperature measurement rate and an initial calibration rate, and a first instance of calibration is carried out according to the initial calibration rate and a first instance of temperature measurement is requested according to the initial temperature measurement rate.

14. The method of claim 8 wherein determining at least one of the temperature measurement rate and the calibration rate comprises:

retrieving the at least one of the temperature measurement rate and the calibration rate from a look-up table using the measured temperature.

15. A computer program product having a computer readable medium tangibly embodying computer executable instructions recorded thereon for dynamically adjusting clock calibration in a wireless communication device, the computer executable instructions comprising:

code for receiving a signal representing a measured temperature;

code for determining at least one of a temperature measurement rate and a calibration rate based on the measured temperature; and

code for transmitting a signal representing the at least one of the determined temperature measurement rate and the determined calibration rate.

16. The computer program product of claim 15 further comprising:

code for receiving a signal to bring the wireless communication device into a sleep mode;

code for determining whether calibration is current; and

code for sending a signal to wait for calibration to be current before entering sleep mode, if the calibration is not current.

17. The computer program product of claim 16 wherein code for determining whether calibration is current comprises:

code for checking a stored indicator of whether the calibration is current.

18. The computer program product of claim 15 further comprising:

code for calibrating the secondary clock at the determined calibration rate; and

code for requesting a temperature measurement at the determined temperature measurement rate.

19. The computer program product of claim 18 wherein the secondary clock is calibrated against the primary clock.

20. The computer program product of claim 18 wherein the wireless communication device is preset with an initial temperature measurement rate and an initial calibration rate, and a first instance of calibration is carried out according to the initial calibration rate and a first instance of temperature measurement is requested according to the initial temperature measurement rate.

21. The computer program product of claim 15 wherein the code for determining at least one of the temperature measurement rate and the calibration rate comprises:

code for retrieving the at least one of the temperature measurement rate and the calibration rate from a look-up table using the measured temperature.