METHOD AND APPARATUS FOR H-ARQ SCHEDULING IN A WIRELESS COMMUNICATION SYSTEM

• US 20100107028A1
• Filed: 10/15/2009
• Published: 04/29/2010
• Est. Priority Date: 10/24/2008
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Hou, Jilei, Gorokhov, Alexei Y.
• Granted Patent: US 8,738,981 B2
• Time in Patent Office: Days
• US Class Current: 714/748
• CPC Class Codes: H04L 1/1812 Hybrid protocols; Hybrid automatic repeat request [HARQ]
• CPC Class Codes: H04L 5/0035 Resource allocation in a cooperative multipoint environment

Abstract

Systems and methodologies are described herein that facilitate Hybrid Automatic Repeat Request (H-ARQ) scheduling and coordination in a wireless communication system. As described herein, a network node capable of cooperation with other nodes for communication to respective users can coordinate a cooperation strategy across nodes based on a H-ARQ protocol to be utilized for a given user. In the case of a synchronous H-ARQ protocol, communication can be scheduled as described herein such that initial transmissions to a user are conducted cooperatively and re-transmissions are conducted without inter-node cooperation. In the case of a H-ARQ protocol utilizing persistent assignments, transmission intervals can be calculated and utilized based on application latency requirements, backhaul link latency, or other factors. In the case of an asynchronous H-ARQ protocol, repeat transmissions can be coordinated in a similar manner to initial transmissions or conducted without inter-node cooperation based on latency sensitivity of an associated application.

Claims

1. A method, comprising:

identifying a Hybrid Automatic Repeat Request (H-ARQ) protocol to be utilized for communication with one or more users; and

selecting a cooperation strategy to be utilized across respective network nodes for communication with the one or more users based at least in part on the H-ARQ protocol.

2. The method of claim 1, wherein the identifying comprises identifying a synchronous H-ARQ protocol to be utilized for communication with one or more users.

3. The method of claim 2, wherein the selecting comprises:

configuring respective initial H-ARQ transmissions to be conducted in a cooperative manner across a plurality of cooperating network nodes; and

configuring respective H-ARQ re-transmissions to occur without inter-node cooperation.

4. The method of claim 3, wherein:

the selecting further comprises scheduling respective transmission instances in advance of communication with the one or more users; and

the configuring respective initial H-ARQ transmissions comprises configuring the respective initial H-ARQ transmissions to occur on the respective transmission instances.

5. The method of claim 2, wherein the selecting comprises:

determining whether a transmission to a given user is pre-schedulable;

configuring the transmission to be conducted in a cooperative manner across a plurality of cooperating network nodes upon determining that the transmission is pre-schedulable; and

configuring the transmission to occur without inter-node cooperation upon determining that the transmission is not pre-schedulable.

6. The method of claim 1, wherein the identifying comprises identifying a H-ARQ protocol to be utilized in combination with persistent assignments associated with one or more users.

7. The method of claim 6, wherein the selecting comprises:

identifying one or more timescales associated with a persistent assignment for a given user; and

selecting one or more transmission intervals for cooperative transmissions to the given user based at least in part on the one or more timescales.

8. The method of claim 7, wherein the identifying one or more timescales comprises identifying one or more timescales based on at least one of latency requirements of an application associated with the persistent assignment or latency of a backhaul link associated with respective associated network nodes.

9. The method of claim 7, wherein the selecting further comprises:

selecting a plurality of transmission intervals for cooperative transmissions to the given user; and

selecting a transmission interval from the plurality of transmission intervals based at least in part on a buffer level associated with the given user.

10. The method of claim 1, wherein the selecting comprises:

configuring a first transmission interval and a second transmission interval, wherein the second transmission interval is longer than the first transmission interval; and

selecting a transmission interval for cooperative communication across respective network nodes from the first transmission interval and the second transmission interval based at least in part on timing requirements associated with at least one of the one or more users or the respective network nodes.

11. The method of claim 10, wherein the selecting a transmission interval comprises selecting the first transmission interval upon determining that a buffer level of the one or more users is substantially large, that user latency requirements dictate a substantially short transmission interval, or that a resource assignment associated with the one or more users is substantially small.

12. The method of claim 10, wherein the selecting a transmission interval comprises selecting the second transmission interval upon determining that expiration of a buffer associated with the one or more users is imminent or that a time interval between respective transmissions conducted by the respective network nodes is configured to be sufficiently large to support coordinated re-transmissions.

13. The method of claim 1, wherein the identifying comprises identifying an asynchronous H-ARQ protocol to be utilized for communication with one or more users.

14. The method of claim 13, further comprising transmitting a data packet to one or more users and identifying a request for re-transmission of the data packet, wherein the selecting further comprises scheduling re-transmission of the data packet as a function of latency sensitivity of an application associated with the data packet.

15. The method of claim 14, wherein the selecting further comprises scheduling re-transmission of the data packet without inter-node cooperation upon determining that the application associated with the data packet is a latency-sensitive application.

16. The method of claim 14, wherein the selecting further comprises scheduling cooperative transmission of a redundancy version of the data packet across a plurality of network nodes upon determining that the application associated with the data packet is not a latency-sensitive application.

17. A wireless communications apparatus, comprising:

a memory that stores data relating to a user equipment unit (UE) served by the wireless communications apparatus and a Hybrid Automatic Repeat Request (H-ARQ) protocol configured for communication with the UE; and

a processor configured to configure a cooperation strategy to be utilized by the wireless communications apparatus and one or more associated network nodes for communication with the UE based at least in part on the H-ARQ protocol configured for communication with the UE.

18. The wireless communications apparatus of claim 17, wherein the H-ARQ protocol configured for communication with the UE is a synchronous H-ARQ protocol.

19. The wireless communications apparatus of claim 18, wherein the processor is further configured to facilitate respective initial transmissions to the UE in cooperation with one or more associated network nodes and to facilitate respective re-transmissions to the UE without cooperation from associated network nodes.

20. The wireless communications apparatus of claim 19, wherein the processor is further configured to pre-schedule a set of transmission instances and to facilitate respective initial transmissions to the UE on transmission instances in the set of transmission instances.

21. The wireless communications apparatus of claim 18, wherein the processor is further configured to classify respective transmissions to the UE as advance schedulable or non-advance schedulable, to facilitate respective advance schedulable transmissions to the UE in cooperation with one or more associated network nodes, and to facilitate respective non-advance schedulable transmissions to the UE without cooperation from associated network nodes.

22. The wireless communications apparatus of claim 17, wherein the H-ARQ protocol configured for communication with the UE is associated with one or more persistent resource assignments designated for the UE.

23. The wireless communications apparatus of claim 22, wherein the processor is further configured to identify one or more timescales associated with a persistent resource assignment to the UE based on at least one of latency requirements of an application associated with the persistent resource assignment or latency of a backhaul link between the wireless communications apparatus and at least one associated network node and to compute at least one transmission interval for communication with the UE based on the one or more timescales.

24. The wireless communications apparatus of claim 23, wherein the processor is further configured to compute a plurality of transmission intervals for communication with the UE and to select a transmission interval from the plurality of transmission intervals based at least in part on a buffer level associated with the UE.

25. The wireless communications apparatus of claim 17, wherein:

the memory further stores data relating to a first transmission interval and a second transmission interval that is longer than the first transmission interval; and

the processor is further configured to select the first transmission interval or the second transmission interval for cooperative communication by the wireless communications apparatus and one or more associated network nodes based at least in part on timing requirements associated with the UE, the wireless communications apparatus, or the one or more associated network nodes.

26. The wireless communications apparatus of claim 25, wherein the processor is further configured to select the first transmission interval upon determining that a buffer level of the UE is substantially large, that UE latency requirements require use of the first transmission interval, or that a resource assignment for the UE is substantially small, or to select the second transmission interval upon determining that expiration of a buffer associated with the UE is imminent or that a time interval between respective transmissions conducted by the wireless communications apparatus and the one or more associated network nodes is configured to be sufficiently large to support coordinated re-transmissions.

27. The wireless communications apparatus of claim 17, wherein the H-ARQ protocol configured for communication with the UE is an asynchronous H-ARQ protocol.

28. The wireless communications apparatus of claim 27, wherein the processor is further configured to conduct a transmission to the UE, to identify a request for repetition of the transmission from the UE, and to configure a cooperation strategy to be utilized for repetition of the transmission based at least in part on latency sensitivity of an application associated with the transmission.

29. The wireless communications apparatus of claim 28, wherein the processor is further configured to facilitate repetition of the transmission without inter-node cooperation upon determining that the application associated with the transmission is a latency-sensitive application.

30. The wireless communications apparatus of claim 28, wherein the processor is further configured to facilitate repetition of the transmission in cooperation with one or more associated network nodes upon determining that the application associated with the transmission is not a latency-sensitive application.

31. An apparatus, comprising:

means for identifying a Hybrid Automatic Repeat Request (H-ARQ) scheme utilized for communication with an associated terminal; and

means for coordinating with one or more associated network nodes to facilitate transmission to the associated terminal based at least in part on a H-ARQ scheme utilized for communication with the associated terminal.

32. The apparatus of claim 31, wherein the H-ARQ scheme utilized for communication with the associated terminal is a synchronous H-ARQ scheme.

33. The apparatus of claim 32, wherein the means for coordinating comprises:

means for scheduling respective initial transmissions to the associated terminal to be conducted in cooperation with the one or more associated network nodes; and

means for scheduling respective repeat transmissions to the associated terminal to be conducted without cooperation from the one or more associated network nodes.

34. The apparatus of claim 33, wherein:

the apparatus further comprises means for scheduling respective transmission instances in advance of communication with the associated terminal; and

the means for scheduling respective initial transmissions comprises means for configuring respective initial transmissions to occur on the respective transmission instances.

35. The apparatus of claim 32, wherein the means for coordinating comprises:

means for determining whether a transmission to the associated terminal is pre-schedulable;

means for scheduling the transmission to be conducted in cooperation with the one or more associated network nodes upon determining that the transmission is pre-schedulable; and

means for scheduling the transmission to be conducted without cooperation from the one or more associated network nodes upon determining that the transmission is not pre-schedulable.

36. The apparatus of claim 31, wherein the H-ARQ scheme utilized for communication with the associated terminal leverages a persistent assignment of resources designated for the associated terminal.

37. The apparatus of claim 36, wherein the means for coordinating comprises:

means for determining respective timescales associated with the persistent assignment based on at least one of latency requirements of an application associated with the persistent assignment or latency of a backhaul link between the apparatus and respective associated network nodes; and

means for computing one or more time intervals for communication with the associated terminal based at least in part on the respective timescales.

38. The apparatus of claim 37, wherein the means for coordinating further comprises:

means for computing a plurality of time intervals for communication with the associated terminal; and

means for selecting a time interval for communication with the associated terminal based at least in part on a buffer level of the associated terminal.

39. The apparatus of claim 31, wherein the H-ARQ scheme utilized for communication with the associated terminal is an asynchronous H-ARQ scheme.

40. The apparatus of claim 39, wherein:

the apparatus further comprises means for conducting a transmission to the associated terminal and means for identifying a request for repetition of the transmission from the associated terminal; and

the means for coordinating comprises means for coordinating with one or more associated network nodes to facilitate repetition of the transmission based at least in part on latency sensitivity of an application associated with the transmission.

41. A computer program product, comprising:

a computer-readable medium, comprising;

code for causing a computer to identify a Hybrid Automatic Repeat Request (H-ARQ) scheme utilized for communication with a user equipment unit (UE); and

code for causing a computer to coordinate with one or more associated network nodes to facilitate transmission to the UE based at least in part on a H-ARQ scheme utilized for communication with the UE.

42. The computer program product of claim 41, wherein the H-ARQ scheme utilized for communication with the UE is a synchronous H-ARQ scheme.

43. The computer program product of claim 42, wherein the code for causing a computer to coordinate comprises:

code for causing a computer to schedule respective initial transmissions to the UE in cooperation with the one or more associated network nodes; and

code for causing a computer to schedule respective repeat transmissions to the UE without cooperation from the one or more associated network nodes.

44. The computer program product of claim 43, wherein:

the computer-readable medium further comprises code for causing a computer to schedule respective transmission instances in advance of communication with the UE; and

the code for causing a computer to schedule respective initial transmissions comprises code for causing a computer to schedule respective initial transmissions on the respective transmission instances.

45. The computer program product of claim 42, wherein the code for causing a computer to coordinate comprises:

code for causing a computer to determine whether a transmission to the UE is pre-schedulable;

code for causing a computer to schedule the transmission in cooperation with the one or more associated network nodes upon determining that the transmission is pre-schedulable; and

code for causing a computer to schedule the transmission without cooperation from the one or more associated network nodes upon determining that the transmission is not pre-schedulable.

46. The computer program product of claim 41, wherein the H-ARQ scheme utilized for communication with the UE leverages a persistent assignment of resources designated for the UE.

47. The computer program product of claim 46, wherein the code for causing a computer to coordinate comprises:

code for causing a computer to determine respective timescales associated with the persistent assignment based on at least one of latency requirements of an application associated with the persistent assignment or latency of a backhaul link between the apparatus and respective associated network nodes; and

code for causing a computer to calculate one or more time intervals for communication with the UE based at least in part on the respective timescales.

48. The computer program product of claim 47, wherein the code for causing a computer to coordinate further comprises:

code for causing a computer to calculate a plurality of time intervals for communication with the UE; and

code for causing a computer to select a time interval for communication with the UE based at least in part on a buffer level of the UE.

49. The computer program product of claim 41, wherein the H-ARQ scheme utilized for communication with the UE is an asynchronous H-ARQ scheme.

50. The computer program product of claim 49, wherein:

the computer-readable medium further comprises code for causing a computer to conduct a transmission to the UE and code for causing a computer to identify a request for repetition of the transmission from the UE; and

the code for causing a computer to coordinate comprises code for causing a computer to coordinate with one or more associated network nodes to facilitate repetition of the transmission based at least in part on latency sensitivity of an application associated with the transmission.