Systems and methods for recovery after radio link failure

• US 9,258,749 B1
• Filed: 01/12/2015
• Issued: 02/09/2016
• Est. Priority Date: 01/12/2015
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Arumugam, Bhaskaran
• Primary Examiner(s): MIZRAHI, DIANE D
• Application Number:
  US14/595,014
• Time in Patent Office: 393 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: H04J 11/0093 Neighbour cell search
• CPC Class Codes: H04W 36/0061 of neighbour cell information
• CPC Class Codes: H04W 36/0079 in case of hand-off failure or rejection
• CPC Class Codes: H04W 56/00 Synchronisation arrangements
• CPC Class Codes: H04W 76/19 Connection re-establishment

Abstract

Embodiments of the present invention include devices, systems and methods for recovery after radio link failure (RLF). For example, a method for wireless communication is described. The method includes performing a base station identity code (BSIC) reconfirmation for a number of top ranked cells in a received neighbor cell list when a radio link timeout (RLT) counter is less than a counter threshold before radio link failure (RLF). A signal-to-noise ratio (SNR) for the top ranked cells is determined during the BSIC reconfirmation. The method also includes scheduling a system information (SI) decode upon RLF for the top ranked cells that have an SNR greater than an SNR threshold. Other aspects, embodiments, and features are also claimed and described.

Claims

1. A method for wireless communication, comprising:

performing a base station identity code (BSIC) reconfirmation for a number of top ranked cells in a received neighbor cell list when a radio link timeout (RLT) counter is less than a counter threshold before radio link failure (RLF), wherein a signal-to-noise ratio (SNR) for the top ranked cells is determined during the BSIC reconfirmation; and

scheduling a system information (SI) decode upon RLF for the top ranked cells that have an SNR greater than an SNR threshold.

2. The method of claim 1, further comprising:

decoding, upon RLF, the SI of a top ranked cell with a highest SNR without performing a power scan; and

camping on the top ranked cell with the highest SNR.

3. The method of claim 1, further comprising delaying additional BSIC reconfirmations for the top ranked cells for a time period when the RLT counter is greater than zero and less than the counter threshold.

4. The method of claim 1, wherein the top ranked cells are determined based on receive levels of cells in the neighbor cell list.

5. The method of claim 1, wherein the BSIC reconfirmation for the top ranked cells is performed in a dedicated mode before RLF.

6. The method of claim 1, wherein the RLT counter is incremented or decremented based on slow associated control channel (SACCH) decoding.

7. The method of claim 1, wherein the counter threshold is 2, the number of top ranked cells is 3 cells, and the SNR threshold is −

6 decibels.

8. The method of claim 1, wherein performing a BSIC reconfirmation comprises decoding a synchronization channel (SCH).

9. The method of claim 1, wherein the method is performed by a wireless communication device in a GSM network.

10. The method of claim 9, wherein the wireless communication device is a dual-SIM dual-standby (DSDS) device.

11. An electronic device for wireless communication, comprising:

a processor;

memory in electronic communication with the processor; and

instructions stored in the memory, the instructions being executable by the processor to;

perform a base station identity code (BSIC) reconfirmation for a number of top ranked cells in a received neighbor cell list when a radio link timeout (RLT) counter is less than a counter threshold before radio link failure (RLF), wherein a signal-to-noise ratio (SNR) for the top ranked cells is determined during the BSIC reconfirmation; and

schedule a system information (SI) decode upon RLF for the top ranked cells that have an SNR greater than an SNR threshold.

12. The electronic device of claim 11, further comprising instructions executable to:

decode, upon RLF, the SI of a top ranked cell with a highest SNR without performing a power scan; and

camp on the top ranked cell with the highest SNR.

13. The electronic device of claim 11, further comprising instructions executable to delay additional BSIC reconfirmations for the top ranked cells for a time period when the RLT counter is greater than zero and less than the counter threshold.

14. The electronic device of claim 11, wherein the top ranked cells are determined based on receive levels of cells in the neighbor cell list.

15. The electronic device of claim 11, wherein the BSIC reconfirmation for the top ranked cells is performed in a dedicated mode before RLF.

16. The electronic device of claim 11, wherein the RLT counter is incremented or decremented based on slow associated control channel (SACCH) decoding.

17. The electronic device of claim 11, wherein the instructions executable to perform a base BSIC reconfirmation comprise instructions executable to decode a synchronization channel (SCH).

18. A wireless device, comprising:

means for performing a base station identity code (BSIC) reconfirmation for a number of top ranked cells in a received neighbor cell list when a radio link timeout (RLT) counter is less than a counter threshold before radio link failure (RLF), wherein a signal-to-noise ratio (SNR) for the top ranked cells is determined during the BSIC reconfirmation; and

means for scheduling a system information (SI) decode upon RLF for the top ranked cells that have an SNR greater than an SNR threshold.

19. The wireless device of claim 18, further comprising:

means for decoding, upon RLF, the SI of a top ranked cell with a highest SNR without performing a power scan; and

means for camping on the top ranked cell with the highest SNR.

20. The wireless device of claim 18, further comprising means for delaying additional BSIC reconfirmations for the top ranked cells for a time period when the RLT counter is greater than zero and less than the counter threshold.

21. The wireless device of claim 18, wherein the top ranked cells are determined based on receive levels of cells in the neighbor cell list.

22. The wireless device of claim 18, wherein the BSIC reconfirmation for the top ranked cells is performed in a dedicated mode before RLF.

23. The wireless device of claim 18, wherein the RLT counter is incremented or decremented based on slow associated control channel (SACCH) decoding.

24. The wireless device of claim 18, wherein the means for performing a BSIC reconfirmation comprise means for decoding a synchronization channel (SCH).

25. A computer-program product, the computer-program product comprising a non-transitory computer-readable medium having instructions thereon, the instructions comprising:

code for causing an electronic device to perform a base station identity code (BSIC) reconfirmation for a number of top ranked cells in a received neighbor cell list when a radio link timeout (RLT) counter is less than a counter threshold before radio link failure (RLF), wherein a signal-to-noise ratio (SNR) for the top ranked cells is determined during the BSIC reconfirmation; and

code for causing the electronic device to schedule a system information (SI) decode upon RLF for the top ranked cells that have an SNR greater than an SNR threshold.

26. The computer-program product of claim 25, further comprising:

code for causing the electronic device to decode, upon RLF, the SI of a top ranked cell with a highest SNR without performing a power scan; and

code for causing the electronic device to camp on the top ranked cell with the highest SNR.

27. The computer-program product of claim 25, further comprising code for causing the electronic device to delay additional BSIC reconfirmations for the top ranked cells for a time period when the RLT counter is greater than zero and less than the counter threshold.

28. The computer-program product of claim 25, wherein the top ranked cells are determined based on receive levels of cells in the neighbor cell list.

29. The computer-program product of claim 25, wherein the BSIC reconfirmation for the top ranked cells is performed in a dedicated mode before RLF.

30. The computer-program product of claim 25, wherein the code for causing the electronic device to perform a base BSIC reconfirmation comprises code for causing the electronic device to decode a synchronization channel (SCH).