Device, Method, and Apparatus for Offline Discontinuous Reception (DRX) Processing in Cellular Systems

• US 20100331019A1
• Filed: 06/29/2009
• Published: 12/30/2010
• Est. Priority Date: 06/29/2009
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Banister, Brian C., Srinivasan, Shivratna G., Bhattacharjee, Supratik, Chan, Joseph C.
• Granted Patent: US 8,554,251 B2
• Time in Patent Office: Days
• US Class Current: 455/458
• CPC Class Codes: H04W 52/0229 where the received signal is a wanted signal
• CPC Class Codes: H04W 68/00 User notification, e.g. alerting and paging, for incoming communication, change of service or the like
• CPC Class Codes: H04W 76/28 Discontinuous transmission [DTX]; Discontinuous reception [DRX]
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

An apparatus and method for processing signals are disclosed. The apparatus may include a transceiver configured to receive a first paging signal during a first cycle, a memory, and a processor configured to store the received first paging signal in the memory, to switch the transceiver to an off state after the first paging signal is stored in the memory, and to process the stored first paging signal while the transceiver is in the off state.

Claims

1. A method for processing signals, comprising:

switching a transceiver of a mobile device to an on state;

receiving a first paging signal via the transceiver during a first cycle;

storing the received first paging signal in a memory of the mobile device;

switching the transceiver to an off state; and

processing the stored first paging signal while the transceiver is in the off state.

2. The method of claim 1, wherein the processing comprises discontinuous receive (DRX) processing the first paging signal.

3. The method of claim 2, wherein the DRX processing comprises automatic gain control (AGC) processing the first paging signal, generating a second paging signal based on the AGC processing of the first paging signal, and overwriting the stored first paging signal with the second paging signal in the memory.

4. The method of claim 3, wherein the AGC processing comprises computing a low noise amplifier (LNA) gain estimate and a digital variable gain amplifier (DVGA) gain estimate from the first paging signal, storing the LNA gain estimate and the DVGA gain estimate, applying an LNA gain estimate computed from a previous paging signal during a previous cycle to the first paging signal during the first cycle, and applying the stored DVGA gain estimate to the first paging signal during the first cycle so as to generate the second paging signal.

5. The method of claim 4, further comprising applying the stored LNA gain estimate computed from the first paging signal during the first cycle to a subsequent paging signal during a subsequent cycle.

6. The method of claim 5, wherein the DRX processing further comprises frequency processing the second paging signal, generating a third paging signal based on the frequency processing of the second paging signal, and overwriting the stored second paging signal with the third paging signal in the memory.

7. The method of claim 6, wherein the frequency processing comprises computing a frequency error factor of the second paging signal, storing the frequency error factor, and applying the stored frequency error factor to the second paging signal during the first cycle so as to generate the third paging signal.

8. The method of claim 7, wherein the DRX processing further comprises time processing the third paging signal, generating a fourth paging signal based on the time processing of the third paging signal, and overwriting the stored third paging signal with the fourth paging signal in the memory.

9. The method of claim 8, wherein the time processing comprises computing a time error factor of the third paging signal, storing the time error factor, and, if the computed time error factor exceeds a predetermined threshold, applying the computed time error factor to the third paging signal during the first cycle so as to generate the fourth paging signal.

10. The method of claim 8, wherein the time processing comprises computing a time error factor of the third paging signal, storing the time error factor, and, if the computed time error factor does not exceed a predetermined threshold, applying a time error factor computed from the previous paging signal during the previous cycle to the third paging signal during the first cycle so as to generate the fourth paging signal.

11. The method of claim 10, further comprising applying the stored time error factor computed from the third paging signal during the first cycle to the subsequent paging signal during the subsequent cycle.

12. The method of claim 11, wherein the DRX processing further comprises performing a first type of channel and noise estimation of the fourth paging signal if the computed time error factor does not exceed a predetermined threshold, and performing a second type of channel and noise estimation of the fourth paging signal if the computed time error factor exceeds the predetermined threshold.

13. The method of claim 12, wherein the DRX processing further comprises demodulating the fourth paging signal based on the channel and noise estimation.

14. The method of claim 13, wherein the DRX processing further comprises decoding the demodulated fourth paging signal so as to determine whether the received first paging signal is intended for the mobile device.

15. The method of claim 4, wherein the first paging signal is a serving cell sample received from a serving cell base station.

16. The method of claim 15, wherein the AGC processing further comprises applying the LNA gain estimate and the DVGA gain estimate computed from the serving cell sample during the first cycle to a neighbor cell sample during the first cycle.

17. The method of claim 16, wherein the memory comprises a serving cell memory and a neighbor cell memory, and wherein serving cell samples are stored in the serving cell memory, and neighbor cell samples are stored in the neighbor cell memory.

18. The method of claim 1, wherein a duration of the first cycle is determined by a discontinuous receive (DRX) cycle length parameter established by a serving cell base station.

19. A wireless communication apparatus, comprising:

a transceiver configured to receive a first paging signal during a first cycle;

a memory; and

a processor configured to store the received first paging signal in the memory, to switch the transceiver to an off state after the first paging signal is stored in the memory, and to process the stored first paging signal while the transceiver is in the off state.

20. The wireless communication apparatus of claim 19, wherein the processor is further configured to perform discontinuous receive (DRX) processing on the first paging signal.

21. The wireless communication apparatus of claim 20, wherein the processor is further configured to perform automatic gain control (AGC) processing on the first paging signal, to generate a second paging signal based on the AGC processing of the first paging signal, and to overwrite the stored first paging signal with the second paging signal in the memory.

22. The wireless communication apparatus of claim 21, wherein processor is further configured to compute a low noise amplifier (LNA) gain estimate and a digital variable gain amplifier (DVGA) gain estimate from the first paging signal, to store the LNA gain estimate and the DVGA gain estimate, to apply an LNA gain estimate computed from a previous paging signal during a previous cycle to the first paging signal during the first cycle, and to apply the stored DVGA gain estimate to the first paging signal during the first cycle so as to generate the second paging signal.

23. The wireless communication apparatus of claim 22, wherein the processor is further configured to apply the stored LNA gain estimate computed from the first paging signal during the first cycle to a subsequent paging signal during a subsequent cycle.

24. The wireless communication apparatus of claim 23, wherein the processor is further configured to perform frequency processing on the second paging signal, to generate a third paging signal based on the frequency processing of the second paging signal, and to overwrite the stored second paging signal with the third paging signal in the memory.

25. The wireless communication apparatus of claim 24, wherein the processor is further configured to compute a frequency error factor of the second paging signal, to store the frequency error factor, and to apply the stored frequency error factor to the second paging signal during the first cycle so as to generate the third paging signal.

26. The wireless communication apparatus of claim 25, wherein the processor is further configured to perform time processing on the third paging signal, to generate a fourth paging signal based on the time processing of the third paging signal, and to overwrite the stored third paging signal with the fourth paging signal in the memory.

27. The wireless communication apparatus of claim 26, wherein the processor is further configured to compute a time error factor of the third paging signal, to store the time error factor, and, if the computed time error factor exceeds a predetermined threshold, to apply the computed time error factor to the third paging signal during the first cycle so as to generate the fourth paging signal.

28. The wireless communication apparatus of claim 26, wherein the processor is further configured to compute a time error factor of the third paging signal, to store the time error factor, and, if the computed time error factor does not exceed a predetermined threshold, to apply a time error factor computed from the previous paging signal during the previous cycle to the third paging signal during the first cycle so as to generate the fourth paging signal.

29. The wireless communication apparatus of claim 28, wherein the processor is further configured to apply the stored time error factor computed from the third paging signal during the first cycle to the subsequent paging signal during the subsequent cycle.

30. The wireless communication apparatus of claim 29, wherein the processor is further configured to perform a first type of channel and noise estimation of the fourth paging signal if the computed time error factor does not exceed a predetermined threshold, and to perform a second type of channel and noise estimation of the fourth paging signal if the computed time error factor exceeds the predetermined threshold.

31. The wireless communication apparatus of claim 30, wherein the processor is further configured to demodulate the fourth paging signal based on the channel and noise estimation.

32. The wireless communication apparatus of claim 31, wherein the processor is further configured to decode the demodulated fourth paging signal so as to determine whether the received first paging signal is intended for the mobile device.

33. The wireless communication apparatus of claim 22, wherein the first paging signal is a serving cell sample received from a serving cell base station.

34. The wireless communication apparatus of claim 33, wherein the processor is further configured to apply the LNA gain estimate and the DVGA gain estimate computed from the serving cell sample during the first cycle to a neighbor cell sample during the first cycle.

35. The wireless communication apparatus of claim 34, wherein the memory comprises a serving cell memory and a neighbor cell memory, and wherein serving cell samples are stored in the serving cell memory, and neighbor cell samples are stored in the neighbor cell memory.

36. The wireless communication apparatus of claim 19, wherein a duration of the first cycle is determined by a discontinuous receive (DRX) cycle length parameter established by a serving cell base station.

37. An apparatus, comprising:

means for switching a transceiver of a mobile device to an on state;

means for receiving a first paging signal via the transceiver during a first cycle;

means for storing the received first paging signal in a memory of the mobile device;

means for switching the transceiver to an off state; and

means for processing the stored first paging signal while the transceiver is in the off state.

38. A computer program product, comprising:

a computer-readable medium comprising;

a first set of codes for causing a computer to switch a transceiver of a mobile device to an on state;

a second set of codes for causing a computer to receive a first paging signal via the transceiver during a first cycle;

a third set of codes for causing a computer to store the received first paging signal in a memory of the mobile device;

a fourth set of codes for causing a computer to switch the transceiver to an off state;

and a fifth set of codes for causing a computer to process the stored first paging signal while the transceiver is in the off state.

39. A wireless communications apparatus, comprising:

at least one processor configured to;

switch a transceiver of a mobile device to an on state;

receive a first paging signal via the transceiver during a first cycle;

store the received first paging signal in a memory of the mobile device;

switch the transceiver to an off state; and

process the stored first paging signal while the transceiver is in the off state.