UL OUT-OF-SYNCHRONIZATION FOR A SECONDARY CELL CARRYING PUCCH

• US 20150245307A1
• Filed: 01/29/2015
• Published: 08/27/2015
• Est. Priority Date: 02/21/2014
• Status: Abandoned Application

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Chen, Wanshi, Damnjanovic, Jelena, Gaal, Peter
• Application Number:
  US14/609,379
• Publication Number:
  US 20150245307A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04L 5/001 the frequencies being arranged in component carriers
• CPC Class Codes: H04L 5/0035 Resource allocation in a cooperative multipoint environment
• CPC Class Codes: H04L 7/0016 correction of synchronization errors
• CPC Class Codes: H04W 56/0005 synchronizing of arrival of multiple uplinks
• CPC Class Codes: H04W 56/0045 compensating for timing error by altering transmission time
• CPC Class Codes: H04W 72/00 Local resource management

Abstract

Methods, systems, and devices are described for uplink synchronization for physical uplink control channel (PUCCH) enabled secondary cells (SCells). A UE may be able to determine that synchronization with a PUCCH-enabled SCell (“PUCCH-SCell”) is lost and to initiate synchronization. Additionally or alternatively, a base station may be configured to expediently determine that a UE has lost synchronization with a PUCCH SCell, and it may initiate synchronization. Either a UE or a base station, or both, may be configured to initiate synchronization depending on a particular carrier aggregation or dual-connectivity may be configured to determine that synchronization has been lost and initiate re-synchronization. In some embodiments, initiating a synchronization procedure may include a base station sending a PDCCH order on a PUCCH SCell, or a UE sending a random access preamble or an unsynchronization alert message on a PUCCH SCell.

Claims

1. A method of communicating in a wireless communication network configured to support multiple component carriers, the method comprising:

determining that a physical uplink control channel equipped secondary component carrier (PUCCH-SCC) is unsynchronized; and

initiating a synchronization procedure.

2. The method of claim 1, wherein:

the PUCCH-SCC comprises a component carrier of a secondary timing adjustment group (sTAG); and

initiating the synchronization procedure comprises transmitting an unsynchronization alert message.

3. The method of claim 2, further comprising:

communicating with a first base station via a primary component carrier (PCC); and

communicating with a second base station via the PUCCH-SCC, wherein the first and second base stations are connected via a non-ideal backhaul, and wherein the PUCCH-SCC is configured for dual-connectivity.

4. The method of claim 2, wherein the transmitting is conditioned on a triggering event.

5. The method of claim 2, wherein the unsynchronization alert message comprises one of a medium access control signal or a radio resource control signal.

6. The method of claim 2, wherein the transmitting comprises transmitting on a component carrier of a master cell group.

7. The method of claim 1, wherein:

the PUCCH-SCC comprises a component carrier of a secondary timing adjustment group (sTAG); and

initiating the synchronization procedure comprises receiving an unsynchronization alert message.

8. The method of claim 7, wherein the unsynchronization alert message comprises one of a medium access control signal or a radio resource control signal.

9. The method of claim 7, wherein receiving comprises receiving the unsynchronization alert message from a base station of a master cell group via a backhaul link.

10. The method of claim 1, wherein initiating the synchronization procedure comprises:

determining that a channel or signal of the PUCCH-SCC is undetected for a threshold period of time;

electing, based on the determination that the channel or signal is undetected, to cease downlink or uplink scheduling for a secondary component carrier associated with the PUCCH-SCC; and

transmitting, based on the determination that the channel or signal is undetected, an order on a physical downlink control channel of the PUCCH-SCC to perform a random access procedure.

11. The method of claim 1, wherein the PUCCH-SCC and a primary component carrier (PCC) comprise component carriers of a common timing adjustment group.

12. The method of claim 1, wherein the PUCCH-SCC comprises a component carrier of a secondary timing adjustment group (sTAG) and a primary component carrier (PCC) comprises a component carrier of a primary timing adjustment group (pTAG).

13. The method of claim 1, wherein initiating the synchronization procedure comprises:

transmitting a random access preamble on a physical random access channel of the PUCCH-SCC in an absence of receiving an order on a physical downlink control channel to perform random access procedures; and

wherein the PUCCH-SCC is configured for carrier aggregation, and the PUCCH-SCC comprises a component carrier of a secondary timing adjustment group (sTAG).

14. The method of claim 13, wherein:

determining the PUCCH-SCC is unsynchronized comprises determining a timing adjustment (TA) timer for the sTAG expired; and

initiating the synchronization procedure further comprises at least one of;

flushing a hybrid automatic repeat request buffer for a component carrier;

signaling for a release of PUCCH or a sounding reference signal for a component carrier;

purging a configured downlink assignment or an uplink grant;

or

treating all TA timers as expired.

15. The method of claim 13, further comprising:

communicating with a first base station via a primary component carrier (PCC); and

communicating with the first base station via the PUCCH-SCC, wherein the PUCCH-SCC is configured for carrier aggregation.

16. The method of claim 1, wherein:

the PUCCH-SCC is configured for carrier aggregation;

the PUCCH-SCC comprises a component carrier of a secondary timing adjustment group; and

initiating the synchronization procedure comprises receiving a random access preamble on a physical random access channel of the PUCCH-SCC in an absence of transmitting an order on a physical downlink control channel to perform random access procedures.

17. A system for communicating in a wireless communication network configured to support multiple component carriers, the system comprising:

means for determining that a physical uplink control channel equipped secondary component carrier (PUCCH-SCC) is unsynchronized; and

means for initiating a synchronization procedure.

18. The system of claim 17, wherein:

the PUCCH-SCC comprises a component carrier of a secondary timing adjustment group (sTAG); and

the means for initiating the synchronization procedure comprises means for transmitting an unsynchronization alert message.

19. The system of claim 18, further comprising:

means for communicating with a first base station via a primary component carrier (PCC); and

means for communicating with a second base station via the PUCCH-SCC, wherein the first and second base stations are connected via a non-ideal backhaul, and wherein the PUCCH-SCC is configured for dual-connectivity.

20. The system of claim 17, wherein initiating the synchronization procedure comprises:

means for transmitting a random access preamble on a physical random access channel of the PUCCH-SCC in an absence of receiving an order on a physical downlink control channel to perform random access procedures; and

wherein the PUCCH-SCC is configured for carrier aggregation, and the PUCCH-SCC comprises a component carrier of a secondary timing adjustment group (sTAG).

21. An apparatus for communicating in a wireless communication network configured to support multiple component carriers, the apparatus comprising:

a processor;

memory in electronic communication with the processor; and

instructions stored on the memory, the instructions are executable by the processor to;

determine that a physical uplink control channel equipped secondary component carrier (PUCCH-SCC) is unsynchronized; and

initiate a synchronization procedure.

22. The apparatus of claim 21, wherein:

the PUCCH-SCC comprises a component carrier of a secondary timing adjustment group (sTAG); and

the instructions are executable by the processor to transmit an unsynchronization alert message.

23. The apparatus of claim 22, wherein the instructions are executable by the processor to:

communicate with a first base station via a primary component carrier (PCC); and

communicate with a second base station via the PUCCH-SCC, wherein the first and second base stations are connected via a non-ideal backhaul, and wherein the PUCCH-SCC is configured for dual-connectivity.

24. The apparatus of claim 22, wherein the transmitting is conditioned on a triggering event.

25. The apparatus of claim 21, wherein:

the PUCCH-SCC comprises a component carrier of a secondary timing adjustment group (sTAG); and

the instructions are executable to receive an unsynchronization alert message.

26. The apparatus of claim 21, wherein the PUCCH-SCC and a primary component carrier (PCC) comprise component carriers of a common timing adjustment group.

27. The apparatus of claim 21, wherein the PUCCH-SCC comprises a component carrier of a secondary timing adjustment group (sTAG) and a primary component carrier (PCC) comprises a component carrier of a primary timing adjustment group (pTAG).

28. The apparatus of claim 21, wherein the instructions are executable by the processor to:

transmit a random access preamble on a physical random access channel of the PUCCH-SCC in an absence of receiving an order on a physical downlink control channel to perform random access procedures; and

wherein the PUCCH-SCC is configured for carrier aggregation, and the PUCCH-SCC comprises a component carrier of a secondary timing adjustment group (sTAG).

29. The apparatus of claim 28, wherein the instructions are executable by the processor to:

communicate with a first base station via a primary component carrier (PCC); and

communicate with the first base station via the PUCCH-SCC, wherein the PUCCH-SCC is configured for carrier aggregation.

30. A non-transitory computer-readable medium storing code for communicating in a wireless communication network configured to support multiple component carriers, the code comprising instructions executable to:

determine that a physical uplink control channel equipped secondary component carrier (PUCCH-SCC) is unsynchronized; and

initiate a synchronization procedure.