Cellular communication system, apparatus and method for management of backhaul resources

• US 7,948,962 B2
• Filed: 08/31/2007
• Issued: 05/24/2011
• Est. Priority Date: 08/31/2007
• Status: Active Grant

• Current Assignee: NVIDIA Corporation
• Original Assignee: Wireless Technology Solutions LLC
• Inventors: Legg, Peter J., Calvert, Stephen R., Latham, Mark
• Primary Examiner(s): Sam; Phirin
• Application Number:
  US11/849,184
• Publication Number:
  US 20090059790A1
• Time in Patent Office: 1,362 Days
• Field of Search: None
• US Class Current: 370/348
• CPC Class Codes: H04L 47/2416 Real-time traffic
• CPC Class Codes: H04L 47/50 Queue scheduling
• CPC Class Codes: H04L 47/521 Static queue service slot or fixed bandwidth allocation
• CPC Class Codes: H04L 47/525 by redistribution of residual bandwidth
• CPC Class Codes: H04W 28/02 Traffic management, e.g. flow control or congestion control
• CPC Class Codes: H04W 72/56 based on priority criteria
• CPC Class Codes: H04W 8/04 Registration at HLR or HSS [Home Subscriber Server]
• CPC Class Codes: H04W 92/12 between access points and access point controllers

Abstract

A communication network element comprises traffic scheduler logic capable of scheduling transmission of a first category of queued traffic across a backhaul interface in accordance with a rate control value. The communication network element further comprises traffic manager logic capable of scheduling transmission of a second category of queued traffic across the backhaul interface in accordance with a determined backhaul bandwidth allocation, the backhaul bandwidth allocation being based on a determination of available bandwidth across the backhaul interface not required for scheduled first category traffic.

Claims

1. A communication network element comprising:

traffic scheduler logic operable to schedule transmission of a first category of queued traffic across a backhaul interface in accordance with a rate control value, wherein the rate control value is based on at least one of;

at least one control input, wherein the at least one control input comprises at least one of a mean bit rate and a buffer occupancy value for at least one of;

not-just-in-time (NJIT) traffic;

just-in-time (JIT) traffic; and

control signalling traffic, and

a strategy for sharing the backhaul interface bandwidth between the first and second categories of traffic; and

traffic manager logic operable to schedule transmission of a second category of queued traffic across the backhaul interface in accordance with a determined backhaul bandwidth allocation,

wherein the backhaul bandwidth allocation is based upon a determination of available bandwidth across the backhaul interface, and the available bandwidth is not required for scheduled first category traffic.

2. The communication network element of claim 1, wherein scheduling transmission of the first category of queued traffic across the backhaul interface by the traffic scheduler logic comprises scheduling transmission of the first category of queued traffic across an air-interface, via the backhaul interface.

3. The communication network element of claim 1, wherein at least one of the traffic manager logic and the traffic scheduler logic generate frame protocol messages for queued traffic scheduled for transmission across the backhaul interface.

4. The communication network element of claim 1, wherein the backhaul sharing strategy comprises at least one of:

a guaranteed throughput for the second category of traffic, and

a fair share of the backhaul interface bandwidth.

5. The communication network element of claim 4, wherein the fair share is determined by a number of timeslots configured for at least one of the first category of traffic and the second category of traffic.

6. The communication network element of claim 1, wherein the rate control value comprises a backhaul bit rate for the first category of traffic.

7. The communication network element of claim 6, wherein the backhaul bit rate for the first category of traffic is calculated by subtracting a second category of traffic cost from a determined available backhaul interface bandwidth.

8. The communication network element of claim 7, wherein the second category of traffic cost represents a bit rate that is to be reserved for the second category of traffic.

9. The communication network element of claim 7, wherein the backhaul bit rate for the first category of traffic is calculated by subtracting the second category of traffic cost from the determined available backhaul interface bandwidth, based on control signalling traffic.

10. The communication network element of claim 9, wherein the second category of traffic cost is calculated based on, for the second category of traffic, at least one of:

a mean data rate, and

a rate required to clear a current buffer occupancy.

11. The communication network element of claim 10, wherein the second category of traffic cost is constrained to be within a minimum value and a maximum value.

12. The communication network element of claim 1, wherein the traffic scheduler logic is operable to schedule the first category of traffic up to a bandwidth determined by the rate control value.

13. The communication network element of claim 1, further comprising arbitrator logic operably coupled to the traffic scheduler logic, wherein the arbitrator logic is operable to generate the rate control value, and further operable to provide the rate control value to the traffic scheduler logic.

14. The communication network element of claim 1, wherein the determination of available bandwidth across the backhaul interface, upon which the backhaul bandwidth allocation is based, is calculated by subtracting, from available bits of the backhaul interface bandwidth, at least one of:

at least one buffer occupancy value, and

at least one control signalling bandwidth allocation.

15. The communication network element of claim 14, wherein the at least one buffer occupancy value comprises at least one scheduled first category traffic buffer occupancy value.

16. The communication network element of claim 14, wherein the at least one buffer occupancy value comprises at least one buffer occupancy value for scheduled traffic other than the first category of traffic or the second category of traffic.

20. The communication network element of claim 1, wherein the traffic scheduler logic is operable to schedule the transmission of the first category of traffic less often than the traffic manager logic is operable to schedule the transmission of the second category of traffic.

21. The communication network element of claim 1, wherein the traffic scheduler logic is operable to schedule the transmission of the first category of traffic approximately every 10 milliseconds.

22. The communication network element of claim 1, wherein the traffic manager logic is operable to schedule the transmission of the second category of traffic approximately every 1 millisecond.

23. The communication network element of claim 1, wherein the first category of traffic comprises traffic scheduled on an air-interface by a base station controller.

24. The communication network element of claim 1, wherein the first category of traffic comprises ‘

Just-In-Time’

(JIT) traffic.

25. The communication network element of claim 24, wherein the first category of traffic comprises Downlink Shared Channel (DSCH) traffic.

26. The communication network element of claim 1, wherein the second category of traffic comprises traffic scheduled on an air-interface by a base station.

29. The communication network element of claim 1, wherein the communication network element is operable to support communication in a time division duplex code division multiple access cellular communication system.

30. The communication network element of claim 1, wherein the communication network element is operable to support communication in a frequency division duplex code division multiple access cellular communication system.

31. The communication network element of claim 1, wherein the communication network element is operable to support communication in a 3rd Generation Partnership Project (3GPP) cellular communication network.

32. The communication network element of claim 1, wherein the communication network element comprises one of:

a radio network controller,

a base station controller.

33. The communication network element of claim 32, wherein the backhaul interface comprises an I_ub interface.

34. A communication system comprising a communication network element according to claim 1.

17. A communication network element comprising:

traffic scheduler logic operable to schedule transmission of a first category of queued traffic across a backhaul interface in accordance with a rate control value;

traffic manager logic operable to schedule transmission of a second category of queued traffic across the backhaul interface in accordance with a determined backhaul bandwidth allocation,

interface manager logic operably coupled to the traffic manager logic, wherein the interface manager logic is operable to calculate the backhaul bandwidth allocation, to provide the backhaul bandwidth allocation to the traffic manager logic, and to manage control signalling traffic provided over the backhaul interface, wherein the interface manager logic is coupled to at least one cell client, wherein the at least one cell client is operable to act as an intermediary between the interface manager logic and at least one frame protocol queue and the at least one cell client is operable to report the at least one buffer occupancy value for queued traffic to the interface manager logic;

wherein the backhaul bandwidth allocation is based upon a determination of available bandwidth across the backhaul interface, and the available bandwidth is not required for scheduled first category traffic.

18. The communication network element of claim 17, wherein the interface manager logic is further operable to allocate backhaul interface bandwidth to traffic other than the first category or second category of traffic.

19. The communication network element of claim 17, wherein the interface manager is operable to provide a bandwidth grant limit to the at least one cell client, and upon receipt of a bandwidth grant, the at least one cell client is operable to send at least one queued message across the backhaul interface up to the granted bandwidth limit.

27. A communication network element comprising:

traffic scheduler logic operable to schedule transmission of a first category of queued traffic across a backhaul interface in accordance with a rate control value;

traffic manager logic operable to schedule transmission of a second category of queued traffic across the backhaul interface in accordance with a determined backhaul bandwidth allocation, wherein the second category of traffic comprises ‘

Non Just-In-Time’

(NJIT) traffic;

wherein the backhaul bandwidth allocation is based upon a determination of available bandwidth across the backhaul interface, and the available bandwidth is not required for scheduled first category traffic.

28. The communication network element of claim 27, wherein the second category of traffic comprises High Speed-Downlink Shared Channel (HS-DSCH) traffic.

35. A method for management of backhaul resources within a communication system, the method comprising:

at a network element;

determining available bandwidth across a backhaul interface;

scheduling transmission of a first category of queued traffic across the backhaul interface in accordance with a rate control value, wherein the rate control value is generated based upon at least one of;

at least one control input that comprises at least one of a mean bit rate and a buffer occupancy value for at least one of;

not-just-in-time (NJIT) traffic;

just-in-time (JIT) traffic; and

Control signalling traffic,

a strategy for sharing the backhaul interface bandwidth between the first and second categories of traffic;

determining an available bandwidth allocation across the backhaul interface, wherein the available bandwidth allocation is not required for scheduled first category traffic; and

scheduling transmission of a second category of queued traffic across the backhaul interface in accordance with the available bandwidth allocation.

36. The method of claim 35, wherein scheduling transmission of the first category of queued traffic across the backhaul interface comprises scheduling transmission of the first category of queued traffic across an air-interface, via the backhaul interface.

37. The method of claim 35, wherein scheduling transmission of queued traffic comprises generating frame protocol messages for transmission across the backhaul interface.

38. The method of claim 35, wherein the at least one control input comprises at least one of:

a timeslot split for the first category of traffic and the second category of traffic; and

a backhaul interface bandwidth.

39. The method of claim 35, wherein the strategy for sharing the backhaul comprises at least one of:

determining a guaranteed throughput for the second category of traffic, and

determining a fair share of the backhaul interface bandwidth.

40. The method of claim 39, wherein determining the fair share comprises determining a number of timeslots configured for at least one of the first category of traffic and the second category of traffic.

41. The method of claim 35, wherein the rate control value comprises a backhaul bit rate for the first category of traffic.

42. The method of claim 41, further comprising calculating the backhaul bit rate for the first category of traffic by subtracting a second category of traffic cost from a determined available backhaul interface bandwidth.

43. The method of claim 42, wherein the second category of traffic cost represents a bit rate that is to be reserved for the second category of traffic.

44. The method of claim 43, further comprising calculating the backhaul bit rate for the first category of traffic by subtracting the second category of traffic cost from the determined available bits of the backhaul interface bandwidth, based on traffic other than of the first or second categories of traffic.

45. The method of claim 44, further comprising calculating the second category of traffic cost based upon, for the second category of traffic, at least one of a higher of:

a mean data rate, and

a rate required to clear a buffer occupancy.

46. The method of claim 45, further comprising constraining the second category of traffic cost to be within a minimum value and a maximum value.

47. The method of claim 35, further comprising scheduling the first category of traffic up to a bandwidth determined by the rate control value.

48. The method of claim 35, wherein determining available bandwidth across the backhaul interface comprises subtracting, from available bandwidth of the backhaul interface bandwidth, at least one of:

at least one buffer occupancy value, and

at least one control signalling bandwidth allocation.

49. The method of claim 48, wherein the at least one buffer occupancy value comprises at least one scheduled first category traffic buffer occupancy value.

50. The method of claim 48, wherein the at least one buffer occupancy value further comprises at least one buffer occupancy value for scheduled traffic other than the first category of traffic or the second category of traffic.

51. The method of claim 35, wherein scheduling transmission of the first category of traffic is performed less often than scheduling transmission of the second category of traffic.

52. The method of claim 35, wherein scheduling transmission of the first category of traffic is performed approximately every 10 milliseconds.

53. The method of claim 35, wherein scheduling transmission of the second category of traffic is performed approximately every 1 millisecond.

54. The method of claim 35, wherein the first category of traffic comprises traffic scheduled over an air-interface by a base station controller.

55. The method of claim 35, wherein the first category of traffic comprises ‘

Just-In-Time’

(JIT) traffic.

56. The method of claim 53, wherein the first category of traffic comprises Downlink Shared Channel (DSCH) traffic.

57. The method of claim 35, wherein the second category of traffic comprises traffic scheduled on an air-interface by a base station.

60. The method of claim 35, wherein the method is applied to a time division duplex code division multiple access cellular communication system.

61. The method of claim 35, wherein the method is applied to a communication system in a 3rd Generation Partnership Project (3GPP) cellular communication network.

62. The method of claim 35, wherein the backhaul interface comprises an I_ub interface.

58. A method for management of backhaul resources within a communication system, the method comprising:

at a network element;

determining available bandwidth across a backhaul interface;

scheduling transmission of a first category of queued traffic across the backhaul interface in accordance with a rate control value;

determining an available bandwidth allocation across the backhaul interface, wherein the available bandwidth allocation is not required for scheduled first category traffic; and

scheduling transmission of a second category of queued traffic across the backhaul interface in accordance with the available bandwidth allocation, wherein the second category of traffic comprises ‘

Non Just-In-Time’

(NJIT).

59. The method of claim 58, wherein the second category of traffic comprises High Speed-Downlink Shared Channel (HS-DSCH) traffic.