Fast system recovery in multi-radio-access-technology devices

• US 9,461,684 B2
• Filed: 07/17/2014
• Issued: 10/04/2016
• Est. Priority Date: 07/17/2014
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Krishnamoorthy, Parthasarathy, Batchu, Bhaskara Viswanadham, Nabar, Mihir
• Primary Examiner(s): ZEWDU, MELESS NMN
• Application Number:
  US14/334,470
• Publication Number:
  US 20160020800A1
• Time in Patent Office: 810 Days
• US Class Current: 1/1
• CPC Class Codes: H04B 1/3816 Mechanical arrangements for accommodating identification devices, e.g. cards or chips; with connectors for programming identification devices
• CPC Class Codes: H04B 1/707 using direct sequence modulation
• CPC Class Codes: H04J 11/0069 Cell search, i.e. determining cell identity [cell-ID] design of multiplexing codes H04J13/00; processing access restriction or access information H04W48/16; discovery of network devices for network data management H04W8/005; sounding signals for channel estimation H04L25/0226; structure of reference signals in multicarrier modulation systems H04L27/2613; frame, time or carrier synchronisation in multicarrier modulation systems H04L27/2655
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 56/0035 detecting errors in frequency or phase
• CPC Class Codes: H04W 72/04 Wireless resource allocation

Abstract

Methods and apparatuses are presented for acquiring a wireless system by a multi-subscriber identity module (SIM) user equipment (UE). For example, an example method for acquiring a wireless system is presented that includes conducting, by a first subscription corresponding to a first SIM of the UE, a call using a shared radio resource of the UE. In addition, the example method may include predicting, upon completion of the call, a pilot timing error and a frequency error associated with a pilot signal of a network associated with a second subscription corresponding to a second SIM of the UE. In addition, the example method may include attempting to acquire the pilot signal based on the pilot timing error and the frequency error. As such, the example method may allow the multi-SIM UE to more quickly acquire a wireless system relative to legacy methods. Other aspects, embodiments, and features are also claimed and described.

Claims

1. A method of acquiring a wireless system by a multi-subscriber identity module (SIM) user equipment (UE), the method comprising:

conducting, by a first subscription corresponding to a first SIM of the UE, a call using a shared radio resource of the UE;

predicting, upon completion of the call, a pilot timing error and a frequency error for a pilot signal of a network associated with a second subscription corresponding to a second SIM of the UE; and

attempting to acquire the pilot signal based on the pilot timing error and the frequency error using the shared radio resource.

2. The method of claim 1, further comprising:

calculating a temperature difference between a first temperature of the UE measured before the call and a second temperature measured after completion of the call; and

comparing the pilot timing error to a pilot increment delay associated with the pilot signal;

wherein attempting to acquire the pilot signal based on the timing error and the frequency error occurs where both the temperature difference is less than or equal to a temperature difference threshold and the pilot timing error is less than or equal to the pilot increment delay.

3. The method of claim 2, wherein the temperature difference threshold comprises 4 degrees Celsius.

4. The method of claim 2, wherein the pilot increment delay is based on a pilot pseudonoise offset of a sector associated with a network entity.

5. The method of claim 1, wherein the pilot timing error is based on an elapsed time of the call.

6. The method of claim 1, wherein the pilot signal is transmitted by a cell upon which the second subscription camped immediately preceding the call.

7. The method of claim 1, further comprising:

determining that each of a plurality of pilot signals corresponding to each subscription of the UE is acquired; and

initiating a slotted mode of radio resource allocation based on determining that each of the plurality of pilot signals is acquired.

8. The method of claim 1, further comprising refraining from declaring a system associated with the second subscription lost during the call.

9. A multi-subscriber identity module (SIM) user equipment (UE), comprising:

a communications component configured to conduct, by a first subscription corresponding to a first SIM of the UE, a call using a shared radio resource of the UE;

a pilot timing error predicting component configured to predict, upon completion of the call, a pilot timing error for a pilot signal of a network associated with a second subscription corresponding to a second SIM of the UE;

a frequency error predicting component configured to predict a frequency error for the pilot signal; and

a pilot signal acquisition component configured to attempt to acquire the pilot signal based on the pilot timing error and the frequency error using the shared radio resource.

10. The multi-SIM UE of claim 9, wherein:

the frequency error predicting component is configured to calculate a temperature difference between a first temperature of the UE measured before the call and a second temperature of the UE measured after completion of the call; and

the pilot signal acquisition component is configured to;

compare the pilot timing error to a pilot increment delay associated with the pilot signal; and

attempt to acquire the pilot signal based on the timing error and the frequency error where both the temperature difference is less than or equal to a temperature difference threshold and the pilot timing error is less than or equal to the pilot increment delay.

11. The multi-SIM UE of claim 10, wherein the temperature difference threshold comprises 4 degrees Celsius.

12. The multi-SIM UE of claim 10, wherein the pilot increment delay is based on a pilot pseudonoise offset of a sector associated with a network entity.

13. The multi-SIM UE of claim 9, wherein the pilot timing error is based on an elapsed time of the call.

14. The multi-SIM UE of claim 9, wherein the pilot signal is transmitted by a cell upon which the second subscription camped immediately preceding the call.

15. The multi-SIM UE of claim 9, wherein the communications component is configured to:

determine that each of a plurality of pilot signals corresponding to each subscription of the UE is acquired; and

initiate a slotted mode of radio resource allocation based on determining that each of the plurality of pilot signals is acquired.

16. A multi-subscriber identity module (SIM) user equipment (UE), comprising:

means for conducting, by a first subscription corresponding to a first SIM of the UE, a call using a shared radio resource of the UE;

means for predicting, upon completion of the call, a pilot timing error and a frequency error for a pilot signal of a network associated with the second subscription corresponding to a second SIM of the UE; and

means for attempting to acquire the pilot signal based on the pilot timing error and the frequency error using the shared radio resource.

17. The multi-SIM UE of claim 16, further comprising:

means for calculating a temperature difference between a first temperature of the UE measured before the call and a second temperature of the UE measured after completion of the call; and

means for comparing the pilot timing error to a pilot increment delay associated with the pilot signal; and

means for attempting to acquire the pilot signal based on the timing error and the frequency error where both the temperature difference is less than or equal to a temperature difference threshold and the pilot timing error is less than or equal to the pilot increment delay.

18. The multi-SIM UE of claim 17, wherein the temperature difference threshold comprises 4 degrees Celsius.

19. The multi-SIM UE of claim 17, wherein the pilot increment delay is based on a pilot pseudonoise offset of a sector associated with a network entity.

20. The multi-SIM UE of claim 16, wherein the pilot timing error is based on an elapsed time of the call.

21. The multi-SIM UE of claim 16, wherein the pilot signal is transmitted by a cell upon which the second subscription camped immediately preceding the call.

22. The multi-SIM UE of claim 16, further comprising:

means for determining that each of a plurality of pilot signals corresponding to each subscription of the UE is acquired; and

means for initiating a slotted mode of radio resource allocation based on determining that each of the plurality of pilot signals is acquired.

23. The multi-SIM UE of claim 16, further comprising means for refraining from declaring a system associated with the second subscription lost during the call.

24. A non-transitory computer-readable storage medium, comprising instructions, that when executed by a processor, cause the processor to:

conduct, by a first subscription corresponding to a first subscriber identity module (SIM) of a multi-SIM user equipment (UE), a call using a shared radio resource of the UE;

predict, upon completion of the call, a pilot timing error and a frequency error for a pilot signal of a network associated with a second subscription corresponding to a second SIM of the UE; and

attempt to acquire the pilot signal based on the pilot timing error and the frequency error using the shared radio resource.

25. The non-transitory computer-readable medium of claim 24, further comprising instructions, that when executed by the processor, cause the processor to:

calculate a temperature difference between a first temperature of the UE measured before the call and a second temperature of the UE measured after completion of the call; and

compare the pilot timing error to a pilot increment delay associated with the pilot signal,

wherein attempting to acquire the pilot signal based on the timing error and the frequency error occurs where both the temperature difference is less than or equal to a temperature difference threshold and the pilot timing error is less than or equal to the pilot increment delay.

26. The non-transitory computer-readable medium of claim 25, wherein the temperature difference threshold comprises 4 degrees Celsius.

27. The non-transitory computer-readable medium of claim 25, wherein the pilot increment delay is based on a pilot pseudonoise offset of a sector associated with a network entity.

28. The non-transitory computer-readable medium of claim 24, wherein the pilot timing error is based on an elapsed time of the call.

29. The non-transitory computer-readable medium of claim 24, wherein the pilot signal is transmitted by a cell upon which the second subscription camped immediately preceding the call.

30. The non-transitory computer-readable medium of claim 24, further comprising instructions, that when executed by the processor, cause the processor to:

determine that each of a plurality of pilot signals corresponding to each subscription of the UE is acquired; and

initiate a slotted mode of radio resource allocation based on determining that each of the plurality of pilot signals is acquired.