DATA COMPRESSION TECHNIQUES FOR HANDOVER AND RADIO LINK FAILURE RECOVERY

• US 20160142951A1
• Filed: 11/12/2015
• Published: 05/19/2016
• Est. Priority Date: 11/14/2014
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Balasubramanian, Srinivasan, Ahmadzadeh, Seyed Ali, Maheshwari, Shailesh, Raina, Ashwini, Kapoor, Rohit, Zacharias, Leena, Dalmiya, Vishal
• Granted Patent: US 10,470,090 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04W 36/0033 with transfer of context information
• CPC Class Codes: H04W 36/0235 by transmitting sequence numbers, e.g. SN status transfer

Abstract

A user equipment (UE) and source base station may use data compression techniques for data packets sent between them. During a handover, the source base station may provide data compression context to a target base station, thus enabling the target base station to continue the data compression following the handover without having to reestablish the data compression context. The source base station may determine data compression capabilities of the UE or the target base station, or both, and may communicate the determined data compression capabilities to the UE or target base station. The source base station may identify at least one gap in a sequence of packets received from the UE, and communicate the existence of the gap to the target base station, which may request retransmission of packets associated with the gap.

Claims

1. A method of wireless communication at a source base station, comprising:

determining that a handover of a user equipment (UE) to a target base station is to be performed;

identifying at least one gap in a sequence of packets received from the UE;

determining a data compression capability of the target base station; and

forwarding context information for the UE to the target base station, wherein the context information is based at least in part on the data compression capability of the target base station.

2. The method of claim 1, wherein the sequence of packets received from the UE comprises uplink data packets, wherein the uplink data packets comprise information that is compressed according to a data compression routine.

3. The method of claim 2, wherein determining the data compression capability of the target base station comprises:

determining whether the target base station supports the data compression routine; and

wherein forwarding the context information comprises;

forwarding compression state information associated with packets sequenced after the at least one gap to the target base station, wherein the compression state information facilitates decompression of the packets sequenced after the at least one gap.

4. The method of claim 2, wherein the context information comprises a status report indicative of the at least one gap in the sequence of packets and compression state information associated with the data compression routine.

5. The method of claim 2, wherein forwarding the context information comprises:

forwarding a data compression buffer to the target base station, wherein the data compression buffer comprises a static data compression portion and a non-static data compression portion.

6. The method of claim 5, wherein the static data compression portion is associated with cell-specific data compression and the non-static data compression portion is associated with UE-specific data compression.

7. The method of claim 5, wherein forwarding the data compression buffer to the target base station comprises:

forwarding the non-static data compression portion of the data compression buffer.

8. The method of claim 2, wherein determining the data compression capability of the target base station comprises:

determining that the target base station does not support the data compression routine; and

wherein the context information comprises control information that comprises an identification of a latest sequential uplink packet before the at least one gap in the sequence of packets.

9. The method of claim 8, further comprising:

forwarding an indication of the at least one gap in the sequence of packets.

10. The method of claim 8, further comprising:

determining that a first uplink packet received subsequent to the at least one gap is uncompressed by the data compression routine; and

forwarding the first uplink packet to the target base station.

11. The method of claim 1, wherein the sequence of packets received from the UE comprises acknowledgment information for a sequence of downlink data packets received from the source base station, the sequence of downlink data packets comprising information that is compressed according to a data compression routine;

and

wherein identifying the at least one gap in the sequence of packets received from the UE comprises;

identifying an unacknowledged downlink data packet.

12. The method of claim 11, wherein determining the data compression capability of the target base station comprises:

determining whether the target base station supports the data compression routine; and

forwarding, to the target base station, unacknowledged downlink data packets and one or more downlink data packets subsequent to the unacknowledged downlink data packet for retransmission to the UE according to the data compression routine.

13. The method of claim 1, further comprising:

transmitting a handover message to the UE indicating that the target base station is to be used for subsequent communications, wherein the handover message comprises an indication that the target base station supports a data compression routine used by the source base station and the UE, wherein the indication is based at least in part on determining that the data compression capability of the target base station are compatible with a data compression capability of the source base station.

14. The method of claim 13, wherein the handover message comprises a command to the UE to retransmit a packet associated with the at least one gap.

15. The method of claim 1, further comprising:

transmitting a data compression capability of the UE to the target base station.

16. A method of wireless communication at a target base station, comprising:

receiving a handover indication that a UE is to be handed over from a source base station;

transmitting a data compression capability of the target base station to the source base station;

receiving context information for the UE from the source base station, wherein the context information identifies at least one gap in a sequence of packets sent by the UE to the source base station; and

transmitting to the UE based at least in part on the context information.

17. The method of claim 16, wherein the data compression capability of the target base station are compatible with a data compression capability of the source base station, and wherein the context information comprises data compression context information for the UE.

18. The method of claim 17, wherein the data compression context information is used for processing a packet associated with the at least one gap in the sequence of packets sent by the UE to the source base station.

19. The method of claim 17, wherein transmitting to the UE comprises:

transmitting a status message that identifies the at least one gap in the sequence of packets sent by the UE to the source base station.

20. The method of claim 16, wherein the sequence of packets sent by the UE to the source base station comprises a sequence of uplink data packets, wherein the sequence of uplink data packets comprises information that is compressed according to a data compression routine, and wherein receiving the context information comprises:

receiving additional packets that arrived at the source base station subsequent to the at least one gap in the sequence of packets; and

receiving a data compression buffer from the source base station, the data compression buffer for use in decompressing data contained in an uplink packet associated with the at least one gap.

21. The method of claim 20, wherein the data compression buffer comprises a static data compression portion and a non-static data compression portion.

22. The method of claim 21, further comprising:

receiving the data compression buffer from the source base station comprises receiving the non-static data compression portion of the data compression buffer.

23. The method of claim 16, wherein the sequence of packets sent by the UE to the source base station comprises acknowledgment information for a sequence of downlink data packets sent by the source base station to the UE, the sequence of downlink data packets comprising information that is compressed according to a data compression routine, and wherein the method further comprises:

receiving a downlink data packet associated with the at least one gap in the sequence of downlink data packets sent by the source base station to the UE and one or more data packets subsequent to the at least one gap in the sequence of downlink data packets sent by the source base station to the UE.

24. The method of claim 23, wherein transmitting to the UE comprises:

retransmitting to the UE a downlink data packets according to the data compression routine.

25. The method of claim 16, wherein the data compression capability of the target base station is different from a data compression capability of the source base station.

26. The method of claim 25, wherein transmitting to the UE comprises:

transmitting a status message that identifies the at least one gap in the sequence of packets sent by the UE to the source base station.

27. The method of claim 25, wherein the context information comprises an indication of a latest sequential packet in the sequence of packets sent by the UE to the source base station.

28. The method of claim 27, wherein transmitting to the UE comprises:

transmitting a status message to the UE, the status message comprising an identification of one or more packets subsequent to the latest sequential packet that are to be retransmitted.

29. The method of claim 25, further comprising:

receiving, from the source base station, a downlink data packet unacknowledged by the UE and one or more downlink data packets of the sequence of packets; and

wherein transmitting to the UE comprises;

transmitting the one or more downlink data packets to the UE.

30. A method of wireless communication at a user equipment (UE), comprising:

transmitting packets to a source base station;

receiving a handover message from the source base station that indicates subsequent communications are to be transmitted to a target base station, the handover message including an indication of a data compression capability of the target base station; and

receiving a transmission from the target base station, wherein the transmission is based at least in part on the data compression capability of the target base station.

31. The method of claim 30, wherein transmitting the packets to the source base station comprises:

transmitting a sequence of packets to the source base station, the sequence of packets comprising data that is compressed according to a data compression routine.

32. The method of claim 31, wherein receiving the transmission from the target base station comprises:

receiving a status report that identifies at least one gap in the sequence of packets that were received at the source base station.

33. The method of claim 32, further comprising:

retransmitting at least one packet identified by the status report, the at least one packet comprising data that is compressed according to the data compression capability of the target base station.

34. The method of claim 33, wherein retransmitting the at least one packet identified by the status report comprises:

retransmitting uncompressed data in the at least one packet, wherein the handover message comprises an indication that the target base station does not support the data compression routine.

35. The method of claim 32, wherein the status report identifies a latest sequential packet in an ordered sequence of data packets.

36. The method of claim 35, further comprising:

retransmitting packets subsequent to the latest sequential packet identified by the status report to the target base station.

37. The method of claim 30, wherein transmitting the packets to the source base station comprises:

transmitting an acknowledgment for each packet in a sequence of downlink data packets received from the source base station, the sequence of downlink data packets comprising data that is compressed according to a data compression routine.

38. The method of claim 37, further comprising:

transmitting a status report to the target base station, the status report indicating at least one gap in the sequence of downlink data packets.

39. The method of claim 38, wherein receiving the transmission from the target base station comprises:

receiving one or more retransmitted packets identified by the status report, the one or more retransmitted packets comprising data that is compressed by the target base station according to the data compression routine.

40. An apparatus for wireless communication at a source base station, comprising:

means for determining that a handover of a user equipment (UE) to a target base station is to be performed;

means for identifying at least one gap in a sequence of packets received from the UE;

means for determining a data compression capability of the target base station; and

means for forwarding context information for the UE to the target base station, wherein the context information is based at least in part on the data compression capability of the target base station.

41. An apparatus for wireless communication at a target base station, comprising:

means for receiving a handover indication that a UE is to be handed over from a source base station;

means for transmitting a data compression capability of the target base station to the source base station;

means for receiving context information for the UE from the source base station, wherein the context information identifies at least one gap in a sequence of packets sent by the UE to the source base station; and

means for transmitting to the UE based at least in part on the context information.

42. An apparatus for wireless communication at a user equipment (UE), comprising:

means for transmitting packets to a source base station;

means for receiving a handover message from the source base station that indicates subsequent communications are to be transmitted to a target base station, the handover message including an indication of a data compression capability of the target base station; and

means for receiving a transmission from the target base station, wherein the transmission is based at least in part on the data compression capability of the target base station.

43. An apparatus for wireless communication at source base station, comprising:

a processor;

memory in electronic communication with the processor; and

instructions stored in the memory and operable, when executed by the processor, to cause the apparatus to;

determine that a handover of a user equipment (UE) to a target base station is to be performed;

identify at least one gap in a sequence of packets received from the UE;

determine a data compression capability of the target base station; and

forward context information for the UE to the target base station, wherein the context information is based at least in part on the data compression capability of the target base station.

44. The apparatus of claim 43, wherein the sequence of packets received from the UE comprises uplink data packets, and wherein the uplink data packets comprise information that is compressed according to a data compression routine.

45. The apparatus of claim 44, wherein the instructions are executable by the processor to cause the apparatus to:

determine whether the target base station supports the data compression routine; and

forward compression state information associated with packets sequenced after the at least one gap to the target base station, wherein the compression state information facilitates decompression of the packets sequenced after the at least one gap.

46. The apparatus of claim 44, wherein the context information comprises a status report indicative of the at least one gap in the sequence of packets and compression state information associated with the data compression routine.

47. The apparatus of claim 44, wherein the instructions are executable by the processor to cause the apparatus to:

determine that the target base station does not support the data compression routine; and

wherein the context information comprises control information that comprises an identification of a latest sequential uplink packet before the at least one gap in the sequence of packets.

48. The apparatus of claim 43, wherein the sequence of packets received from the UE comprises acknowledgment information for a sequence of downlink data packets received from the source base station, the sequence of packets comprising information that is compressed according to a data compression routine;

and wherein the instructions are executable by the processor to cause the apparatus to;

identifying an unacknowledged downlink data packet.

49. The apparatus of claim 48, wherein the instructions are executable by the processor to cause the apparatus to:

determine whether the target base station supports the data compression routine; and

forward, to the target base station, unacknowledged downlink data packets and one or more downlink data packets subsequent to the unacknowledged downlink data packet for retransmission to the UE according to the data compression routine.

50. The apparatus of claim 43, wherein the instructions are executable by the processor to cause the apparatus to:

transmit a handover message to the UE indicating that the target base station is to be used for subsequent communications, wherein the handover message comprises an indication that the target base station supports a data compression routine used by the source base station and the UE, wherein the indication is based at least in part on determining that the data compression capability of the target base station is compatible with a data compression capability of the source base station.

51. The apparatus of claim 43, wherein the instructions are executable by the processor to cause the apparatus to:

transmit a data compression capability of the UE to the target base station.

52. An apparatus for wireless communication at a target base station, comprising:

a processor;

memory in electronic communication with the processor; and

instructions stored in the memory and operable, when executed by the processor, to cause the apparatus to;

receive a handover indication that a UE is to be handed over from a source base station;

transmit a data compression capability to the source base station;

receive context information for the UE from the source base station, wherein the context information identifies at least one gap in a sequence of packets sent by the UE to the source base station; and

transmit to the UE based at least in part on the context information.

53. The apparatus of claim 52, wherein the data compression capability of the target base station is compatible with the data compression capability of the source base station, and wherein the context information comprises data compression context information for the UE.

54. The apparatus of claim 53, wherein the data compression context information is used for processing a packet associated with the at least one gap in the sequence of packets sent by the UE to the source base station.

55. The apparatus of claim 52, wherein the sequence of packets sent by the UE to the source base station comprises a sequence of uplink data packets, wherein the sequence of uplink data packets comprises information that is compressed according to a data compression routine, and wherein the instructions are executable by the processor to cause the apparatus to:

receive additional packets that arrived at the source base station subsequent to the at least one gap in the sequence of packets; and

receive a data compression buffer from the source base station, the data compression buffer for use in decompressing data contained in an uplink packet associated with the at least one gap.

56. The apparatus of claim 52, wherein the sequence of packets sent by the UE to the source base station comprises acknowledgment information for a sequence of downlink data packets sent by the source base station to the UE, the sequence of downlink data packets comprising information that is compressed according to a data compression routine, and wherein the instructions are executable by the processor to cause the apparatus to:

receive a downlink data packet associated with the at least one gap in the sequence of downlink data packets sent by the source base station to the UE and one or more data packets subsequent to the at least one gap in the sequence of downlink data packets sent by the source base station to the UE.

57. The apparatus of claim 52, wherein the data compression capability of the target base station is different from the data compression capability of the source base station.

58. The apparatus of claim 57, wherein the instructions are executable by the processor to cause the apparatus to:

transmit a status message that identifies the at least one gap in the sequence of packets sent by the UE to the source base station.

59. The apparatus of claim 57, wherein the context information comprises an indication of a latest sequential packet in the sequence of packets sent by the UE to the source base station.

60. An apparatus for wireless communication at a user equipment (UE), comprising:

a processor;

memory in electronic communication with the processor; and

instructions stored in the memory and operable, when executed by the processor, to cause the apparatus to;

transmit packets to a source base station;

receive a handover message from the source base station that indicates subsequent communications are to be transmitted to a target base station, the handover message including an indication of a data compression capability of the target base station; and

receive a transmission from the target base station, wherein the transmission is based at least in part on the data compression capability of the target base station.

61. The apparatus of claim 60, wherein the instructions are executable by the processor to cause the apparatus to:

transmit a sequence of packets to the source base station, the packets comprising data that is compressed according to a data compression routine.

62. The apparatus of claim 60, wherein the instructions are executable by the processor to cause the apparatus to:

transmit an acknowledgment for each packet in a sequence of downlink data packets received from the source base station, the sequence of downlink data packets comprising data that is compressed according to a data compression routine.

63. A non-transitory computer-readable medium storing code for wireless communication at a source base station, the code comprising instructions executable to:

determine that a handover of a user equipment (UE) to a target base station is to be performed;

identify at least one gap in a sequence of packets received from the UE;

determine a data compression capability of the target base station; and

forward context information for the UE to the target base station, wherein the context information is based at least in part on the data compression capability of the target base station.

64. A non-transitory computer-readable medium storing code for wireless communication at a target base station, the code comprising instructions executable to:

receive a handover indication that a UE is to be handed over from a source base station;

transmit a data compression capability of the target base station to the source base station;

receive context information for the UE from the source base station, wherein the context information identifies at least one gap in a sequence of packets sent by the UE to the source base station; and

transmit to the UE based at least in part on the context information.

65. A non-transitory computer-readable medium storing code for wireless communication at a user equipment (UE), the code comprising instructions executable to:

transmit packets to a source base station;

receive a handover message from the source base station that indicates subsequent communications are to be transmitted to a target base station, the handover message including an indication of a data compression capability of the target base station; and

receive a transmission from the target base station, wherein the transmission is based at least in part on the data compression capability of the target base station.