METHOD AND APPARATUS FOR RELAY BACKHAUL DESIGN IN A WIRELESS COMMUNICATION SYSTEM

• US 20110194483A1
• Filed: 08/10/2010
• Published: 08/11/2011
• Est. Priority Date: 08/12/2009
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Chen, Wanshi, Ji, Tingfang, Lin, Dexu
• Granted Patent: US 9,210,622 B2
• Time in Patent Office: Days
• US Class Current: 370/315
• CPC Class Codes: H04W 36/0033 with transfer of context information
• CPC Class Codes: H04W 36/08 Reselecting an access point
• CPC Class Codes: H04W 36/083 wherein at least one of the access points is a moving node
• CPC Class Codes: H04W 36/165 for reducing network power consumption H04W36/18 - H04W36/22 take precedence
• CPC Class Codes: H04W 36/304 due to measured or perceived resources with higher communication quality
• CPC Class Codes: H04W 72/00 Local resource management
• CPC Class Codes: H04W 88/04 adapted for relaying to or from another terminal or user

Abstract

Systems and methodologies are described herein that facilitate techniques for design of relay backhaul to support mobility of relay nodes in a wireless communication system. According to various aspects herein, techniques are provided to enable and support the use of mobile relays and to facilitate handover of mobile relays between respective donor cells. More particularly, techniques are provided herein for relay backhaul control channel assignment associated with hand in or hand out of mobile relays, access/backhaul resource partitioning for mobile relays, and management of quality of service (QoS) requirements associated with a relay handover.

Claims

1. A method, comprising:

obtaining information relating to an access/backhaul resource partitioning corresponding to an associated relay node;

detecting a requested handover of the associated relay node to a target cell; and

indicating the access/backhaul resource partitioning to the target cell in connection with the requested handover to enable partitioning of access resources and backhaul resources at the target cell based on the access/backhaul resource partitioning.

2. The method of claim 1, wherein the indicating comprises indicating the access/backhaul resource partitioning to the target cell prior to the requested handover.

3. A wireless communications apparatus, comprising:

a memory that stores data relating to a relay node and an access/backhaul resource partitioning corresponding to the relay node; and

a processor configured to detect requested handover of the relay node to a target cell and to indicate the access/backhaul resource partitioning to the target cell in connection with the requested handover.

4. An apparatus, comprising:

means for identifying access resources and backhaul resources corresponding to a relay node; and

means for indicating identities of the access resources and the backhaul resources to a target cell corresponding to a requested handover of the relay node.

5. A computer program product, comprising:

a computer-readable medium, comprising;

code for causing a computer to identify access resources and backhaul resources corresponding to a relay node; and

code for causing a computer to indicate identities of the access resources and the backhaul resources to a target cell corresponding to a requested handover of the relay node.

6. A method, comprising:

detecting a requested handover of a relay node from a source cell;

receiving information from the source cell in connection with the requested handover relating to an access/backhaul resource partitioning utilized by the source cell for the relay node; and

configuring an allocation of access subframes and backhaul subframes corresponding to the relay node based at least in part on information received from the source cell.

7. The method of claim 6, wherein the receiving comprises receiving the information from the source cell prior to the requested handover.

8. The method of claim 6, wherein the configuring comprises configuring an allocation of access subframes and backhaul subframes corresponding to the relay node that substantially preserves the access/backhaul resource partitioning utilized by the source cell for the relay node.

9. The method of claim 6, wherein the configuring comprises configuring an allocation of access subframes and backhaul subframes corresponding to the relay node such that an assigned random access channel (RACH) occasion associated with the relay node occurs on an uplink backhaul subframe corresponding to the relay node.

10. The method of claim 6, wherein the configuring comprises configuring an allocation of access subframes and backhaul subframes corresponding to the relay node such that a random access response (RAR) transmitted to the relay node occurs on a downlink backhaul subframe corresponding to the relay node.

11. The method of claim 6, wherein the configuring comprises configuring an allocation of access subframes and backhaul subframes corresponding to the relay node such that respective non-Multimedia Broadcast over Single-Frequency Network (MBSFN) subframes corresponding to the relay node are allocated as access subframes.

12. The method of claim 11, wherein the configuring further comprises:

identifying a subframe offset corresponding to the relay node;

obtaining information relating to one or more predetermined non-MBSFN subframe positions within a given radio frame; and

determining the one or more predetermined non-MBSFN subframe positions within the given radio frame with respect to the relay node based on the subframe offset corresponding to the relay node.

13. The method of claim 6, further comprising transmitting information to the relay node that indicates the allocation of access subframes and backhaul subframes corresponding to the relay node.

14. The method of claim 13, wherein the transmitting comprises transmitting the information to the relay node during the requested handover of the relay node or after the requested handover of the relay node.

15. The method of claim 13, wherein the transmitting comprises transmitting the information to the relay node using unicast layer 3 (L3) signaling.

16. A wireless communications apparatus, comprising:

a memory that stores data relating to a relay node, a source cell, and a requested handover of the relay node from the source cell; and

a processor configured to receive information from the source cell in connection with the requested handover relating to an access/backhaul resource partitioning utilized by the source cell for the relay node and to determine an allocation of access subframes and backhaul subframes corresponding to the relay node based at least in part on the information received from the source cell.

17. The wireless communications apparatus of claim 16, wherein the processor is further configured to determine an allocation of access subframes and backhaul subframes corresponding to the relay node that substantially preserves the access/backhaul resource partitioning utilized by the source cell for the relay node.

18. The wireless communications apparatus of claim 16, wherein the processor is further configured to determine an allocation of access subframes and backhaul subframes corresponding to the relay node such that an assigned random access channel (RACH) occasion associated with the relay node occurs on an uplink backhaul subframe corresponding to the relay node.

19. The wireless communications apparatus of claim 16, wherein the processor is further configured to determine an allocation of access subframes and backhaul subframes corresponding to the relay node such that a random access response (RAR) transmitted to the relay node occurs on a downlink backhaul subframe corresponding to the relay node.

20. The wireless communications apparatus of claim 16, wherein the processor is further configured to determine an allocation of access subframes and backhaul subframes corresponding to the relay node such that respective non-Multimedia Broadcast over Single-Frequency Network (MBSFN) subframes corresponding to the relay node are allocated as access subframes.

21. The wireless communications apparatus of claim 16, wherein the processor is further configured to transmit information to the relay node that relates to the allocation of access subframes and backhaul subframes corresponding to the relay node.

22. The wireless communications apparatus of claim 21, wherein the processor is further configured to transmit the information to the relay node via unicast layer 3 (L3) signaling during the requested handover of the relay node or after the requested handover of the relay node.

23. An apparatus, comprising:

means for receiving information from a source Evolved Node B (eNB) in response to a requested handover of a relay node from the source eNB relating to a partitioning of access resources and backhaul resources utilized by the source eNB for the relay node; and

means for allocating access resources and backhaul resources for the relay node based at least in part on information received from the source eNB.

24. The apparatus of claim 23, wherein the means for allocating comprises means for allocating access resources and backhaul resources for the relay node such that an assigned random access channel (RACH) occasion associated with the relay node occurs on an uplink backhaul subframe corresponding to the relay node.

25. The apparatus of claim 23, wherein the means for allocating comprises means for allocating access resources and backhaul resources for the relay node such that a random access response (RAR) transmitted to the relay node occurs on a downlink backhaul subframe corresponding to the relay node.

26. The apparatus of claim 23, wherein the means for allocating comprises means for allocating access resources and backhaul resources for the relay node such that respective non-Multimedia Broadcast over Single-Frequency Network (MBSFN) subframes corresponding to the relay node are allocated as access subframes.

27. The apparatus of claim 23, further comprising means for communicating information to the relay node that indicates the access resources and backhaul resources for the relay node.

28. A computer program product, comprising:

a computer-readable medium, comprising;

code for causing a computer to receive information from a source Evolved Node B (eNB) in response to a requested handover of a relay node from the source eNB relating to a partitioning of access resources and backhaul resources utilized by the source eNB for the relay node; and

code for causing a computer to allocate access resources and backhaul resources for the relay node based at least in part on the information received from the source eNB.

29. A method, comprising:

identifying an allocation of access subframes and backhaul subframes associated with relay communication;

initializing a handover from a source Evolved Node B (eNB) to a destination eNB;

obtaining information relating to an access/backhaul subframe allocation utilized by the destination eNB; and

adjusting one or more subframes in the allocation of access subframes and backhaul subframes based on the access/backhaul subframe allocation utilized by the destination eNB.

30. The method of claim 29, wherein the adjusting comprises adjusting one or more subframes in the allocation of access subframes and backhaul subframes prior to the handover.

31. The method of claim 29, wherein the adjusting comprises adjusting one or more subframes in the allocation of access subframes and backhaul subframes in response to a random access channel (RACH) allocation utilized by the destination eNB.

32. The method of claim 31, wherein the adjusting further comprises adjusting one or more subframes in the allocation of access subframes and backhaul subframes such that a RACH occasion assigned by the destination eNB occurs on an uplink backhaul subframe with the destination eNB.

33. The method of claim 31, wherein the adjusting further comprises adjusting one or more subframes in the allocation of access subframes and backhaul subframes such that a random access response (RAR) transmitted by the destination eNB occurs on a downlink backhaul subframe.

34. The method of claim 29, wherein the adjusting comprises adjusting one or more subframes in the allocation of access subframes and backhaul subframes to facilitate substantial conformance with the access/backhaul subframe allocation utilized by the destination eNB.

35. The method of claim 29, further comprising indicating a result of the adjusting to one or more served user equipment units (UEs).

36. The method of claim 29, wherein the adjusting comprises adjusting one or more subframes in the allocation of access subframes and backhaul subframes such that respective non-Multimedia Broadcast over Single-Frequency Network (MBSFN) subframes are allocated as access subframes.

37. A wireless communications apparatus, comprising:

a memory that stores data relating to a source Evolved Node B (eNB) and a destination eNB; and

a processor configured to identify an allocation of access subframes and backhaul subframes associated with relay communication, to initialize a handover from the source eNB to the destination eNB, to obtain information relating to an access/backhaul subframe allocation utilized by the destination eNB, and to adjust one or more subframes in the allocation of access subframes and backhaul subframes based on the access/backhaul subframe allocation utilized by the destination eNB.

38. The wireless communications apparatus of claim 37, wherein the processor is further configured to adjust one or more subframes in the allocation of access subframes and backhaul subframes in response to a random access channel (RACH) allocation utilized by the destination eNB.

39. The wireless communications apparatus of claim 38, wherein the processor is further configured to adjust one or more subframes in the allocation of access subframes and backhaul subframes such that a RACH occasion assigned by the destination eNB occurs on an uplink backhaul subframe with the destination eNB.

40. The wireless communications apparatus of claim 38, wherein the processor is further configured to adjust one or more subframes in the allocation of access subframes and backhaul subframes such that a random access response (RAR) transmitted by the destination eNB occurs on a downlink backhaul subframe.

41. The wireless communications apparatus of claim 37, wherein the processor is further configured to adjust one or more subframes in the allocation of access subframes and backhaul subframes such that respective non-Multimedia Broadcast over Single-Frequency Network (MBSFN) subframes are allocated as access subframes.

42. An apparatus, comprising:

means for identifying an allocation of access resources and backhaul resources associated with relay communication;

means for initializing a relay handover to a target cell; and

means for adjusting at least a portion of the allocation of access resources and backhaul resources based on an access/backhaul resource partitioning associated with the target cell.

43. The apparatus of claim 42, wherein the means for adjusting comprises means for adjusting at least a portion of the allocation of access resources and backhaul resources such that a random access channel (RACH) occasion assigned by the target cell occurs on an uplink backhaul subframe with the target cell.

44. The apparatus of claim 42, wherein the means for adjusting comprises means for adjusting at least a portion of the allocation of access resources and backhaul resources such that a random access response (RAR) transmitted by the target cell occurs on a downlink backhaul subframe.

45. The apparatus of claim 42, wherein the means for adjusting comprises means for adjusting at least a portion of the allocation of access resources and backhaul resources such that respective non-Multimedia Broadcast over Single-Frequency Network (MBSFN) subframes are allocated as access subframes.

46. A computer program product, comprising:

a computer-readable medium, comprising;

code for causing a computer to identify an allocation of access resources and backhaul resources associated with relay communication;

code for causing a computer to initialize a relay handover to a target cell; and

code for causing a computer to adjust at least a portion of the allocation of access resources and backhaul resources based on an access/backhaul resource partitioning associated with the target cell.

47. A method, comprising:

detecting a requested initialization of communication service for a relay node in association with a handover of the relay node;

identifying a quality of service (QoS) requirement for the handover of the relay node; and

directing communication in connection with the handover of the relay node such that the QoS requirement for the handover of the relay node is substantially preserved.

48. The method of claim 47, wherein the directing comprises directing communication of random access signaling associated with the handover of the relay node such that the QoS requirement for the handover of the relay node is substantially preserved.

49. The method of claim 48, wherein the directing further comprises increasing length of respective preamble sequences associated with the random access signaling.

50. The method of claim 48, wherein the directing further comprises decreasing a time interval with which a random access response (RAR) is transmitted to the relay node in response to random access signaling provided by the relay node in connection with the handover of the relay node.

51. The method of claim 47, wherein the directing comprises:

identifying a random access region associated with the relay node in connection with the handover of the relay node; and

abstaining from scheduling transmissions on the random access region associated with the relay node.

52. The method of claim 51, wherein the directing further comprises configuring respective re-transmissions such that respective re-transmissions identified as potentially conflicting with the random access region associated with the relay node in connection with the handover of the relay node are adaptively scheduled on resources disparate from resources corresponding to the random access region associated with the relay node.

53. A wireless communications apparatus, comprising:

a memory that stores data relating to a relay node; and

a processor configured to detect requested initialization of communication service for the relay node in association with a handover of the relay node, to identify a quality of service (QoS) requirement for the handover of the relay node, and to direct communication in connection with the handover of the relay node such that the QoS requirement for the handover of the relay node is substantially preserved.

54. The wireless communications apparatus of claim 53, wherein the processor is further configured to increase length of respective preamble sequences for random access signaling associated with the handover of the relay node.

55. The wireless communications apparatus of claim 53, wherein the processor is further configured to decrease a time interval with which a random access response (RAR) is transmitted to the relay node in response to random access signaling provided by the relay node in connection with the handover of the relay node.

56. The wireless communications apparatus of claim 53, wherein the processor is further configured to identify a random access region associated with the relay node in connection with the handover of the relay node and to abstain from scheduling transmissions or re-transmissions on the random access region associated with the relay node.

57. An apparatus, comprising:

means for detecting initialization of a handover of a relay node and a quality of service (QoS) requirement associated with the handover of the relay node; and

means for managing communication relating to the handover of the relay node such that the QoS requirement associated with the handover of the relay node is substantially met.

58. The apparatus of claim 57, wherein the means for managing comprises means for increasing length of respective preamble sequences for random access signaling associated with the handover of the relay node.

59. The apparatus of claim 57, wherein the means for managing comprises means for decreasing a time interval with which a random access response (RAR) is transmitted to the relay node in response to random access signaling provided by the relay node in connection with the handover of the relay node.

60. The apparatus of claim 57, wherein the means for managing comprises:

means for identifying a random access region associated with the relay node in connection with the handover of the relay node; and

means for abstaining from scheduling transmissions or re-transmissions on the random access region associated with the relay node.

61. A computer program product, comprising:

a computer-readable medium, comprising;

code for causing a computer to detect initialization of a handover of a relay node and a quality of service (QoS) requirement associated with the handover of the relay node; and

code for causing a computer to manage communication relating to the handover of the relay node such that the QoS requirement associated with the handover of the relay node is substantially met.

62. A method, comprising:

initializing a relay handover to a target donor Evolved Node B (eNB);

identifying a quality of service (QoS) requirement for the relay handover; and

directing communication in connection with the relay handover such that the QoS requirement for the relay handover is substantially preserved.

63. The method of claim 62, wherein the directing comprises directing communication of random access signaling associated with the relay handover such that the QoS requirement for the relay handover is substantially preserved.

64. The method of claim 63, wherein the directing further comprises increasing transmission power for initial random access signaling performed in connection with the relay handover.

65. The method of claim 64, wherein the increasing comprises increasing the transmission power for the initial random access signaling based on a predefined relay power offset.

66. The method of claim 63, wherein the directing further comprises decreasing a maximum acceptable time interval at which a random access response (RAR) can be received from the target donor eNB following random access signaling performed in connection with the relay handover.

67. The method of claim 66, wherein the directing further comprises directing re-transmission of the random access signaling if a RAR is not received within the maximum acceptable time interval.

68. The method of claim 62, wherein the directing comprises:

identifying a plurality of candidate target donor eNBs;

detecting a failure of the relay handover to the target donor eNB; and

initializing an alternative relay handover to a candidate target donor eNB selected from the plurality of candidate target donor eNBs in response to detecting the failure of the relay handover to the target donor eNB.

69. A wireless communications apparatus, comprising:

a memory that stores data relating to a target donor Evolved Node B (eNB); and

a processor configured to initialize a relay handover to the target donor eNB, to identify a quality of service (QoS) requirement for the relay handover, and to direct communication in connection with the relay handover such that the QoS requirement for the relay handover is substantially preserved.

70. The wireless communications apparatus of claim 69, wherein the processor is further configured to increase transmission power for initial random access signaling performed in connection with the relay handover.

71. The wireless communications apparatus of claim 69, wherein the processor is further configured to decrease a maximum acceptable time interval at which a random access response (RAR) can be received from the target donor eNB following random access signaling performed in connection with the relay handover.

72. The wireless communications apparatus of claim 69, wherein:

the memory further stores data relating to a plurality of candidate target donor eNBs; and

the processor is further configured to detect a failure of the relay handover to the target donor eNB and to initialize an alternative relay handover to a candidate target donor eNB selected from the plurality of candidate target donor eNBs in response to detecting the failure of the relay handover to the target donor eNB.

73. An apparatus, comprising:

means for identifying a target cell for a relay handover and a quality of service (QoS) requirement associated with the relay handover; and

means for managing communication relating to the relay handover such that the QoS requirement associated with the relay handover is substantially met.

74. The apparatus of claim 73, wherein the means for managing comprises means for increasing transmission power for initial random access signaling performed in connection with the relay handover.

75. The apparatus of claim 73, wherein the means for managing comprises means for decreasing a maximum acceptable time interval at which a random access response (RAR) can be received from the target cell following random access signaling performed in connection with the relay handover.

76. The apparatus of claim 73, wherein the means for managing comprises:

means for identifying a plurality of candidate target cells;

means for detecting a failure of the relay handover to the target cell; and

means for initializing an alternative relay handover to a candidate target cell selected from the plurality of candidate target cells in response to detecting the failure of the relay handover to the target cell.

77. A computer program product, comprising:

a computer-readable medium, comprising;

code for causing a computer to identify a target cell for a relay handover and a quality of service (QoS) requirement associated with the relay handover; and

code for causing a computer to manage communication relating to the relay handover such that the QoS requirement associated with the relay handover is substantially met.