Systems, methods, and apparatus for activity control in a wireless communications device

• US 20070178875A1
• Filed: 06/28/2006
• Published: 08/02/2007
• Est. Priority Date: 06/28/2005
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Rao, Anil, Rao, Subramanya
• Granted Patent: US 8,385,878 B2
• Time in Patent Office: Days
• US Class Current: 455/343.100
• CPC Class Codes: H04W 52/028 switching on or off only a part of the equipment circuit blocks
• CPC Class Codes: H04W 56/0035 detecting errors in frequency or phase
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

Embodiments include methods of activity control in which a time of initiation of an active period of a discontinuous reception (DRX) cycle is based on a value calculated with respect to a wireless signal received during an active period of a previous DRX cycle.

Claims

1. A method of activity control, said method comprising:

during an active period of a first discontinuous reception (DRX) cycle, receiving a wireless signal;

based on the received wireless signal, calculating a value; and

based on the calculated value, calculating a starting time for the active period of a second DRX cycle subsequent to the first DRX cycle,

wherein the calculated value indicates at least one among (A) a quality of the received wireless signal and (B) an error of at least one among time and frequency with respect to the received wireless signal.

2. The method of activity control according to claim 1, said method comprising, during a paging slot within the active period of the first DRX cycle, monitoring a paging channel.

3. The method of activity control according to claim 2, said method comprising decoding a plurality of paging indicator bits received during the paging slot.

4. The method of activity control according to claim 1, wherein said receiving includes correcting a frequency error of an oscillator with respect to the received wireless signal, and

wherein the calculated value is based on the corrected frequency error.

5. The method of activity control according to claim 1, wherein said receiving includes correcting a timing error with respect to the received wireless signal, and

wherein the calculated value is based on the corrected timing error.

6. The method of activity control according to claim 1, wherein said receiving includes correcting a code phase error with respect to the received wireless signal, and

wherein the calculated value is based on the corrected code phase error.

7. The method of activity control according to claim 1, wherein said calculating a starting time includes:

based on the calculated value, calculating a predicted track time of at least one among a frequency tracking loop and a time tracking loop; and

based on the predicted track time, calculating the starting time.

8. The method of activity control according to claim 1, wherein the calculated value is based on a calculated energy of the received wireless signal.

9. The method of activity control according to claim 1, said method comprising, during an active period of a third DRX cycle prior to the first and second DRX cycles, calculating a second value based on a received wireless signal,

wherein said calculating a starting time is based on the calculated second value.

10. The method of activity control according to claim 1, wherein said calculating a starting time includes selecting an interval from among a plurality of intervals, and

wherein said selecting is based on the calculated value.

11. The method of activity control according to claim 1, said method comprising programming a sleep timer according to the calculated starting time.

12. A data storage medium having machine-executable instructions describing the method of activity control according to claim 1.

13. An apparatus for wireless communications, said apparatus comprising:

an oscillator configured to produce a frequency reference;

a radio-frequency (RF) receiver arranged to receive the frequency reference, wherein the RF receiver is configured to receive a wireless signal according to the frequency reference;

a sleep timer configured and arranged to activate said oscillator during the active periods of each of a plurality of discontinuous reception (DRX) cycles; and

a calculator configured to calculate, according to a value based on at least one among (A) a quality of a wireless signal received by said RF receiver during the active period of a first one of the plurality of DRX cycles and (B) an error of at least one among time and frequency with respect to a wireless signal received by said RF receiver during the active period of the first one of the plurality of DRX cycles, a starting time for the active period of a second one of the plurality of DRX cycles subsequent to the first one.

14. The apparatus for wireless communications according to claim 13, wherein said RF receiver is configured to monitor a paging channel during a paging slot within the active period of the first one of the plurality of DRX cycles.

15. The apparatus for wireless communications according to claim 14, wherein said RF receiver is configured to decode a plurality of paging indicator bits received during the paging slot.

16. The apparatus for wireless communications according to claim 13, wherein said apparatus includes a frequency tracking loop configured to correct a frequency error of the oscillator with respect to the received wireless signal,

wherein said calculator is configured to calculate the starting time according to a value based on the corrected frequency error.

17. The apparatus for wireless communications according to claim 16, wherein said RF receiver includes a signal strength calculator configured to calculate a value indicating the strength of the received wireless signal,

wherein said calculator is configured to calculate the starting time according to a value based on the strength of the received wireless signal.

18. The apparatus for wireless communications according to claim 13, wherein said RF receiver includes a signal strength calculator configured to calculate a value indicating the strength of the received wireless signal,

wherein said calculator is configured to calculate the starting time according to a value based on the strength of the received wireless signal.

19. The apparatus for wireless communications according to claim 13, wherein said RF receiver includes an energy calculator configured to calculate a value indicating the strength of the received wireless signal,

wherein said calculator is configured to calculate the starting time according to a value based on the strength of the received wireless signal.

20. The apparatus for wireless communications according to claim 13, wherein said RF receiver includes a time tracking loop configured to correct a timing error with respect to the received wireless signal,

wherein said calculator is configured to calculate the starting time according to a value based on the corrected timing error.

21. The apparatus for wireless communications according to claim 13, wherein said RF receiver includes a code tracking loop configured to correct a code phase error with respect to the received wireless signal,

wherein said calculator is configured to calculate the starting time according to a value based on the corrected code phase error.

22. The apparatus for wireless communications according to claim 13, wherein said calculator is configured to calculate the starting time according to a value based on a wireless signal received during an active period of a third DRX cycle prior to the first and second DRX cycles.

23. The apparatus for wireless communications according to claim 13, wherein said calculator is configured to select an interval from among a plurality of intervals according to the calculated value, and

wherein said sleep timer is configured to activate said oscillator according to the selected interval.

24. The apparatus for wireless communications according to claim 13, wherein said calculator is configured to calculate, according to the calculated value, a predicted track time for at least one among a frequency error and a timing error, and

wherein said calculator is configured to calculate the starting time based on the predicted track time.

25. The apparatus for wireless communications according to claim 13, wherein said apparatus includes a lookup table, and

wherein said calculator is configured to select a value from said lookup table according to the calculated value, and

wherein said calculator is configured to calculate the starting time based on the selected value.

26. The apparatus for wireless communications according to claim 13, wherein said apparatus is a portable wireless communication device.

27. The apparatus for wireless communications according to claim 26, wherein said apparatus is a cellular telephone.

28. An apparatus for wireless communications, said apparatus comprising:

means for receiving a wireless signal during an active period of a first discontinuous reception (DRX) cycle;

means for calculating a value based on the received wireless signal; and

means for calculating, based on the calculated value, a starting time for the active period of a second DRX cycle subsequent to the first DRX cycle,

wherein the calculated value indicates at least one among (A) a quality of the received wireless signal and (B) an error of at least one among time and frequency with respect to the received wireless signal.

29. The apparatus for wireless communications according to claim 28, wherein said means for receiving is configured to monitor a paging channel during a paging slot within the active period of the first DRX cycle.

30. The apparatus for wireless communications according to claim 29, wherein said means for receiving is configured to decode a plurality of paging indicator bits received during the paging slot.

31. The apparatus for wireless communications according to claim 28, wherein said means for receiving is configured to correct a frequency error of an oscillator with respect to the received wireless signal, and

wherein said means for calculating a value is configured to produce the calculated value based on the corrected frequency error.

32. The apparatus for wireless communications according to claim 28, wherein said means for receiving is configured to correct a timing error with respect to the received wireless signal, and

wherein said means for calculating a value is configured to produce the calculated value based on the corrected timing error.

33. The apparatus for wireless communications according to claim 28, wherein said means for receiving is configured to correct a code phase error with respect to the received wireless signal, and

wherein said means for calculating a value is configured to produce the calculated value based on the corrected code phase error.

34. The apparatus for wireless communications according to claim 28, wherein said means for calculating a value is configured to produce the calculated value based on a calculated energy of the received wireless signal.

35. The apparatus for wireless communications according to claim 28, wherein said means for calculating a value is configured to calculate a second value based on a wireless signal received during an active period of a third DRX cycle prior to the first and second DRX cycle,

wherein said means for calculating a starting time is configured to calculate the starting time based on the calculated second value.

36. The apparatus for wireless communications according to claim 28, wherein said means for calculating a starting time is configured to select, based on the calculated value, an interval from among a plurality of intervals.

37. The apparatus for wireless communications according to claim 28, wherein said means for calculating a starting time is configured to program a sleep timer according to the calculated starting time.

38. The apparatus for wireless communications according to claim 28, wherein said apparatus is a portable wireless communication device.

39. The apparatus for wireless communications according to claim 38, wherein said apparatus is a cellular telephone.