Packet data traffic control for cellular wireless networks

• US 7,310,529 B1
• Filed: 01/24/2000
• Issued: 12/18/2007
• Est. Priority Date: 01/24/2000
• Status: Expired due to Fees

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Nortel Networks Limited (Nortel Networks Corporation)
• Inventors: Lodge, Richard A., Lie Chin Cheong, Patrick
• Primary Examiner(s): Tran, Pablo N.
• Application Number:
  US09/489,929
• Time in Patent Office: 2,885 Days
• Field of Search: 455/67.3, 455/67.1, 455 8- 10, 455/450, 455/423, 455512-517, 455/513, 455/422, 455/452, 455/426, 455560-561, 455/557, 455/445, 455 68- 69, 455/15, 455/455, 455/422.1, 455/501, 455509-510, 4554521-4522, 455/67.11, 455/67.13, 370/468, 370/329, 370/338, 370/348, 370/408, 370252-253, 370/332, 370/407, 370/410, 370/401, 370/400, 709224-227, 709/238, 375/220, 374/220
• US Class Current: 455/445
• CPC Class Codes: H04W 28/18 Negotiating wireless communication parameters
• CPC Class Codes: H04W 72/541 using the level of interference
• CPC Class Codes: H04W 72/542 using measured or perceived quality
• CPC Class Codes: H04W 76/20 Manipulation of established connections

Abstract

Data traffic over a plurality of data communications links of a wireless data communications system is controlled by identifying a poorly performing wireless link, and interrupting data communications over the poorly performing link. The data throughput of remaining links between the transceivers is thus increased due to reduced interference and increased available band-width, because the poorly performing link is no longer transmitting. Interruption of data communications over the poorly performing link may be accomplished by suspending or dropping transmission of a frame. If a frame is predicted to be certain to violate quality of service (QoS) requirements, the frame may be preemptively suspended or dropped. If multiple frames are dropped within a predetermined period, a communications session over the poorly performing link may be dropped. Data communications over the poorly performing link can be resumed following a selected delay period, which may have a random length.

Claims

1. A method of controlling data traffic in a wireless data communications network comprising a plurality of wireless terminals and a base station, each wireless terminal being adapted for bi-directional data communication with the base station through a respective bi-directional wireless data communications link, the method comprising steps of, at the base station:

a) examining performance of each wireless link to identify a poorly performing wireless link; and

b) temporarily interrupting bi-directional data transmission over the poorly performing wireless link.

2. A method as claimed in claim 1, wherein the step of examining performance of the wireless links comprises steps of monitoring one or more performance parameters related to each wireless link, and comparing each monitored performance parameter to a respective predetermined threshold value.

3. A method as claimed in claim 2, wherein the one or more performance parameters related to each wireless link are based on any one or more of a quality-of-service (QOS), and interference on the wireless link.

4. A method as claimed in claim 3, wherein at least one of the performance parameters related to each wireless link is based on interference on the wireless link, and comprises any one or more of:

a signal-to-noise (S/N) ratio;

a user data throughput rate;

a carrier-to-interference (C/I) ratio;

a bit-error-rate (BER); and

a number of suspended frames.

5. A method as claimed in claim 4, wherein at least one of the performance parameters related to each wireless link comprises an average, taken over a number n of successive bursts, of any one or more of the S/N ratio;

the C/I ratio;

the user data throughput rate; and

the BER.

6. A method as claimed in claim 3, wherein at least one of the performance parameters related to each wireless link is a QOS performance parameter

7. A method as claimed in claim 6, further comprising maintaining a count of dropped frames.

8. A method as claimed in claim 7, further comprising a step of dropping the session if the number of dropped frames exceeds a predetermined threshold.

9. A method as claimed in claim 6, wherein the step of monitoring a respective performance parameter respecting each wireless link comprises a step of predicting whether a QOS performance parameter is certain to violate a corresponding QOS requirement of a communications session on the link.

10. A method as claimed in claim 9, wherein the step of interrupting data transmission over the poorly performing wireless link comprises a step of preemptively dropping a data frame being transmitted over the poorly performing wireless link.

11. A method as claimed in claim 1, wherein the step of interrupting data transmission over the poorly performing wireless link comprises a step of suspending transmission of a data frame over the poorly performing wireless link.

12. A method as claimed in claim 11, further comprising a step of resuming transmission of the data frame after a delay period.

13. A method as claimed in claim 12, wherein the delay period is a period of random length.

14. A method as claimed in claim 11, further comprising maintaining a count of suspended frames.

15. A method as claimed in claim 14, further comprising suspending a communications session over the wireless link if the count of suspended frames exceeds a predetermined threshold.

16. A method as claimed in claim 15, further comprising restarting the session after a delay period.

17. A method as claimed in claim 16, wherein the delay period is of random length. comprising any one or more of a data transmission delay, and a number of dropped frames.

18. A method as claimed in claim 1, wherein the step of interrupting data transmission over the poorly performing wireless link comprises a step of dropping a data frame transmitted over the poorly performing wireless link.

19. A method as claimed in claim 18, further comprising a step of re-transmitting the dropped frame after a delay period.

20. A method as claimed in claim 19, wherein the delay period is a period of random length.

21. A wireless data communications network comprising a base station capable of bi-directional data communication with each one of a plurality of wireless terminals over respective bi-directional wireless data communications links, the base station comprising:

a) computing means for examining performance of each wireless link of the network to identify a poorly performing wireless link; and

b) control means for temporarily interrupting bi-directional data transmission over the identified poorly performing wireless link.

22. A network as claimed in claim 21, wherein the computing means comprises means for monitoring one or more performance parameters related to each wireless link, and comparing each monitored performance parameter to a respective predetermined tolerance.

23. A network as claimed in claim 22, wherein the one or more performance parameters related to each wireless link are based on any one or more of a quality-of-service (QOS), and interference on the wireless link.

24. A network as claimed in claim 23, wherein at least one of the performance parameters related to each wireless link is based on interference on the link, and comprises any one or more of:

a signal-to-noise (S/N) ratio;

a carrier-to-interference (C/I) ratio;

a bit-error-rate (BER);

a user data throughput rate; and

a number of suspended frames.

25. A network as claimed in claim 24, wherein at least one of the performance parameters related to each wireless link comprises an average, taken over a number n of successive bursts, of any one or more of the S/N ratio;

the C/I ratio;

the user data throughput rate; and

the BER.

26. A network as claimed in claim 23, wherein at least one of the performance parameters concerning each wireless link is a QOS performance parameter comprising any one or more of a data transmission delay, and a number of dropped frames.

27. A network as claimed in claim 26, wherein the control means is adapted to drop a data frame transmitted over the poorly performing wireless link.

28. A network as claimed in claim 27, further comprising means for re-transmitting the dropped frame after a delay period.

29. A network as claimed in claim 28, wherein the delay period is a period of random length.

30. A network as claimed in claim 26, wherein the computing means is adapted to maintain a count of dropped frames.

31. A network as claimed in claim 30, wherein the control means is adapted to drop the session if the count of dropped frames exceeds a predetermined threshold.

32. A network as claimed in claim 26, wherein the computing means is adapted to compute a probability respecting whether the QOS performance parameter in certain to violate a corresponding QOS requirement of a communications session on the link.

33. A network as claimed in claim 32, wherein the control means is adapted to preemptively drop a data frame being transmitted over the poorly performing wireless link.

34. A network as claimed in claim 21, wherein the control means is adapted to suspend transmission of a data frame over the poorly performing wireless link.

35. A network as claimed in claim 34, further comprising means for resuming transmission of the data frame after a delay period.

36. A network as claimed in claim 35, wherein the delay period is a period of random length.

37. A network as claimed in claim 34, wherein the computing means is further adapted to maintain a count of suspended frames.

38. A network as claimed in claim 37, wherein the control means is adapted to suspend a communications session over the wireless link if the count of suspended frames exceeds a predetermined threshold.

39. A network as claimed in claim 38, further comprising means for restarting the session after a delay period.

40. A network as claimed in claim 39, wherein the delay period is of random length.

41. A base station of a wireless data communications network, the base station being adapted for bi-directional data communications with each one of a plurality of wireless terminals over respective bi-directional wireless communications links, the base station comprising:

a) computing means for examining performance of each wireless link of the network to identify a poorly performing wireless link; and

b) control means for temporarily interrupting bidirectional data transmission over the identified poorly performing wireless link.

42. A base station as claimed in claim 41, wherein the computing means comprises means for monitoring one or more performance parameters related to each wireless link, and comparing each monitored performance parameter to a respective predetermined tolerance.

43. A base station as claimed in claim 42, wherein the one or more performance parameters related to each wireless link are based on any one or more of a quality-of-service (QOS), and interference on the link.

44. A base station as claimed in claim 43, wherein at least one of the performance parameters related to each wireless link is based on interference on the link, and comprises any or more of:

a signal-to-noise (S/N) ratio;

a user data throughput rate;

a carrier-to-interference (C/I) ratio;

a bit-error-rate (BER); and

a number of suspended frames.

45. A base station as claimed in claim 44, wherein at least one of the performance parameters related to each wireless link comprises an average, taken over a number n of successive bursts, of any one or more of the S/N ratio;

the C/I ratio;

the user data throughput rate; and

the BER.

46. A base station as claimed in claim 44, wherein the control means is adapted to suspend transmission of a data frame over the poorly performing wireless link.

47. A base station as claimed in claim 46, wherein the computing means is further adapted to maintain a count of a number of suspended frames.

48. A base station as claimed in claim 47, wherein the control means is adapted to suspend a communications session over the link if the count of suspended frames exceeds a predetermined threshold.

49. A base station as claimed in claim 43, wherein at least one of the performance parameters related to each wireless link is a QOS performance parameter comprising any one or more of a data transmission delay, and a number of dropped frames.

50. A base station as claimed in claim 49, wherein the control means is adapted to drop a data frame transmitted over the poorly performing wireless link.

51. A base station as claimed in claim 50, wherein the computing means is adapted to maintain a count of dropped frames.

52. A base station as claimed in claim 51, wherein the control means is adapted to drop the session if the count of dropped frames exceeds a predetermined threshold.

53. A base station as claimed in claim 49, wherein the computing means is adapted to compute a probability respecting whether the QOS performance parameter is certain to violate a corresponding QOS requirement of a communications session on the wireless link.

54. A base station as claimed in claim 53, wherein the control means is adapted to preemptively drop a data frame being transmitted over the poorly performing wireless link.