Performance improvement of internet protocols over wireless connections

• US 6,591,382 B1
• Filed: 08/17/1999
• Issued: 07/08/2003
• Est. Priority Date: 08/17/1999
• Status: Expired due to Term

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: Skyworks Solutions Incorporated
• Inventors: Trotta, Thomas P., Molloy, Walter, Eidson, Donald B.
• Primary Examiner(s): Decady, Albert
• Assistant Examiner(s): ABRAHAM, ESAW T
• Application Number:
  US09/375,607
• Time in Patent Office: 1,421 Days
• Field of Search: 714/704, 714/708, 714/774, 370/342, 370/468, 358/412
• US Class Current: 714/704
• CPC Class Codes: H04L 1/0009 by adapting the channel coding H04L1/1812 takes precedence
• CPC Class Codes: H04L 1/0025 Transmission of mode-switching indication
• CPC Class Codes: H04L 1/16 in which the return channel carries supervisory signals, e.g. repetition request signals
• CPC Class Codes: H04L 1/20 using signal quality detector
• CPC Class Codes: H04L 69/18 Multiprotocol handlers, e.g. single devices capable of handling multiple protocols
• CPC Class Codes: H04L 69/324 in the data link layer [OSI layer 2], e.g. HDLC
• CPC Class Codes: H04W 80/02 Data link layer protocols

Abstract

A system and method for providing improved performance using TCP/IP protocols over wireless networks that can be implemented entirely within the link layer of a protocol stack. The system and method responds to low signal levels caused by weak and fading wireless connections by maintaining throughput and circumventing inappropriate instances of TCP/IP congestion avoidance mode. At least two selectable service protocols, comprising at least one selectable basic error-detecting/correcting protocol and at least one selectable robust error-detecting/correcting protocol, are implemented within link layers of both the mobile station and the base station. A quality of service monitor installed within the link layer monitors signal quality. When the quality of service monitor detects a signal quality that falls below a predetermined threshold or predicts a future signal degradation, the mobile station switches to the robust error-detecting/correcting service protocol and informs the base station of the changeover. The base station similarly switches to the robust error-detecting/correcting service protocol, beginning at a predetermined data frame. If the quality of service rises above a second predetermined threshold, the basic error-detecting/correcting protocols are restored both within the mobile and base stations.

Claims

1. A method for use by a mobile station to improve performance over wireless connections between a base station and the mobile station, said mobile station having at least two service protocols comprising a basic error-detecting/correcting protocol and a robust error-detecting/correction protocol different from the basic error-detecting/correcting protocol, said method comprising the steps of:

establishing a communication link with the base station using the basic error-detecting/correcting protocol over a transmission channel;

monitoring a signal quality of the transmission channel;

determining if the signal quality falls below a first predetermined threshold;

sending a switchover message to the base station to switch from the basic error-detecting/correcting protocol to the robust error-detecting/correcting protocol, if the signal quality falls below the first predetermined threshold; and

switching to the robust error-detecting/correcting protocol.

2. The method of claim 1, further comprising the steps of:

sending a switchover message to the base station to switch from the robust error-detecting/correcting protocol to the basic error-detecting/correcting protocol, if the signal quality rises above a second predetermined threshold; and

switching to the basic error-detecting/correcting protocol.

3. The method of claim 1, wherein the basic error-detecting/correcting protocol is a link access protocol.

4. The method of claim 1, wherein the robust error-detecting/correcting protocol is a forward error correcting protocol.

5. The method of claim 1, further comprising the steps of:

querying the base station to determine if the base station supports the at least two service protocols; and

performing said sending and switching steps only if the base station supports the the at least two service protocols.

6. The method of claim 5, wherein said querying step is performed using XID negotiation during said establishing step.

7. The method of claim 5, wherein said querying step is performed by sending a message to the base station and then waiting for an acknowledgement from the base station to indicate support.

8. The method of claim 1, wherein said step of monitoring the signal quality is performed by monitoring a bit error rate of the communication link.

9. The method of claim 1, wherein said step of monitoring the signal quality is performed by predicting a future change in signal quality.

10. The method of claim 9, wherein said step of predicting a future change in signal quality is accomplished by applying an estimate of signal to noise and interference ratio (SINR).

11. The method of claim 10, wherein said step of applying an estimate of SINR includes subtracting said estimate of the interference and noise power from a measured signal power.

12. The method of claim 11, wherein said SINR is converted into a bit error rate.

13. The method of claim 1, further comprising the step of receiving a switchover acknowledgement from the base station in response to said sending step.

14. The method of claim 1, further comprising the step of querying the base station to determine if the base station supports the at least two service protocols, wherein said querying step occurs between said determining step and said sending step.

15. The method of claim 1, wherein said switchover message includes a parameter indicating the service protocol.

16. The method of claim 1, wherein said switchover message includes a parameter indicating a frame number.

17. The method of claim 16, wherein said switching step occur after a frame having the frame number.

18. A system for providing improved performance over wireless connection comprising:

a mobile station having a protocol stack with a link layer comprising;

at least two service protocols comprising at least one basic error-detecting/correcting protocol and at least one robust error-detecting/correction protocol different from the at least one basic error-detecting/correcting protocol;

a quality of service monitor for determining a signal quality of a transmission channel; and

a protocol selector coupled to said at least one basic error-detecting/correcting protocol and said at least one robust error-detecting/correcting protocol and said quality of service monitor, for selecting among said at least one basic error-detecting/correcting protocol and said at least one robust error-detecting/correcting protocol in accordance with said quality of service monitor; and

a base station having a protocol stack with a link layer comprising;

at least two service protocols comprising at least one basic error-detecting/correcting protocol and at least one robust error-detecting/correction protocol different from the at least one basic error-detecting/correcting protocol; and

a protocol selector coupled to said at least one basic error-detecting/correcting protocol and said at least one robust error-detecting/correcting protocol and said quality of service monitor, for selecting among said at least one basic error-detecting/correcting protocol and said at least one robust error-detecting/correcting protocol in accordance with a switchover message from said mobile station.

19. The system of claim 18, wherein said protocol selector in said mobile station switches from the at least one basic error-detecting/correcting protocol to the at least one robust error-detecting/correcting protocol when said quality monitor indicates a degradation in said signal quality.

20. The system of claim 18, wherein said protocol selector in said mobile station switches from the at least one robust error-detecting/correcting protocol to the at least one basic error-detecting/correcting protocol when said quality monitor indicates an improvement in said signal quality.

21. The system of claim 18, wherein said quality of service monitor is coupled with a quality of service indicator coupled to the physical layer in the protocol stack.

22. The system of claim 21, wherein said quality of service indicator is a data logger that tracks a bit error rate of data communications.

23. The system of claim 21, wherein said quality of service indicator is a measure of a received signal power that is used for predicting a future signal quality.

24. The system of claim 23, wherein said received signal power is derived from relative signal strength indication measurement.

25. A mobile station configured to improve performance over wireless connections between a base station and the mobile station, the mobile station comprising:

at least two service protocols comprising a first error-detecting/correcting protocol and a second error-detecting/correction protocol different from the first error-detecting/correcting protocol;

a link establishment module for establishing a communication link with the base station using the first error-detecting/correcting protocol over a transmission channel;

a quality of service monitor for determining a signal quality of the transmission channel;

a transmitter for sending a switchover message to the base station to switch from the first error-detecting/correcting protocol to the second error-detecting/correcting protocol if the signal quality passes the first predetermined threshold; and

a protocol selector for switching to the second error-detecting/correcting.

26. The mobile station of claim 25, wherein said transmitter sends a switchover message to the base station to switch from the second error-detecting/correcting protocol to the first error-detecting/correcting protocol if the signal quality passes a second predetermined threshold, and wherein the protocol selector switches to the first error-detecting/correcting protocol.

27. The mobile station of claim 25, wherein the first error-detecting/correcting protocol is a link access protocol.

28. The mobile station of claim 25, wherein the second error-detecting/correcting protocol is a forward error correcting protocol.

29. The mobile station of claim 25 further comprising a query module for querying the base station to determine if the base station supports the at least two service protocols, wherein the switchover message is transmitted only if the base station supports the at least two service protocols.

30. The mobile station of claim 29, wherein the query module is a part of the link establishment module and uses XID negotiation.

31. The mobile station of claim 29, wherein the query module sends a message to the base station and then waiting for an acknowledgement from the base station to indicate support.

32. The mobile station of claim 25, wherein the quality of service monitor monitors a bit error rate of the communication link.

33. The mobile station of claim 25, wherein the quality of service monitor predicts a future change in signal quality.

34. The mobile station of claim 33, wherein the quality of service monitor applies an estimate of signal to noise and interference ratio (SINR) to predict the future change in signal quality.

35. The mobile station of claim 34, wherein the quality of service monitor subtracts said estimate of the interference and noise power from a measured signal power.

36. The mobile station of claim 35, wherein said SINR is converted into a bit error rate.

37. The mobile station of claim 25 further comprising a receiver for receiving a switchover acknowledgement from the base station in response to the transmitter sending the switchover message.

38. The mobile station of claim 25 further comprising a query module for querying the base station to determine if the base station supports the at least two service protocols, wherein the query module queries after determining that the signal quality has fallen below the first predetermined threshold, but before sending the switchover message.

39. The mobile station of claim 25, wherein said switchover message includes a parameter indicating the service protocol.

40. The mobile station of claim 25, wherein said switchover message includes a parameter indicating a frame number.

41. The mobile station of claim 40, wherein said switching step occur after a frame having the frame number.

42. The mobile station of claim 25, wherein the first error-detecting/correcting protocol is less robust than the second error-detecting/correcting protocol, and wherein the transmitter sends the switchover message if the signal quality fails below the first predetermined threshold.

43. The mobile station of claim 25, wherein the first error-detecting/correcting protocol is more robust than the second error-detecting/correcting protocol, and wherein the transmitter sends the switchover message if the signal quality rises above the first predetermined threshold.

44. A method for use by a mobile station to improve performance over wireless connections between a base station and the mobile station, said mobile station having at least two service protocols comprising a first error-detecting/correcting protocol and a second error-detecting/correction protocol different from the first error-detecting/correcting protocol, said method comprising the steps of:

establishing a communication link with the base station using the first error-detecting/correcting protocol over a transmission channel;

monitoring a signal quality of the transmission channel;

determining if the signal quality falls below a first predetermined threshold;

sending a switchover message to the base station to switch from the first error-detecting/correcting protocol to the second error-detecting/correcting protocol if the signal quality passes the first predetermined threshold; and

switching to the second error-detecting/correcting protocol.

45. The method of claim 44, further comprising the steps of:

sending a switchover message to the base station to switch from the second error-detecting/correcting protocol to the first error-detecting/correcting protocol if the signal quality passes a second predetermined threshold; and

switching to the first error-detecting/correcting protocol.

46. The method of claim 44, wherein the first error-detecting/correcting protocol is a link access protocol.

47. The method of claim 44, wherein the second error-detecting/correcting protocol is a forward error correcting protocol.

48. The method of claim 44, further comprising the steps of:

querying the base station to determine if the base station supports the at least two service protocols; and

performing said sending and switching steps only if the base station supports the the at least two service protocols.

49. The method of claim 48, wherein said querying step is performed using XID negotiation during said establishing step.

50. The method of claim 48, wherein said querying step is performed by sending a message to the base station and then waiting for an acknowledgement from the base station to indicate support.

51. The method of claim 44, wherein said step of monitoring the signal quality is performed by monitoring a bit error rate of the communication link.

52. The method of claim 44, wherein said step of monitoring the signal quality is performed by predicting a future change in signal quality.

53. The method of claim 52, wherein said step of predicting a future change in signal quality is accomplished by applying an estimate of signal to noise and interference ratio (SINR).

54. The method of claim 53, wherein said step of applying an estimate of SINR includes subtracting said estimate of the interference and noise power from a measured signal power.

55. The method of claim 54, wherein said SINR is converted into a bit error rate.

56. The method of claim 44, further comprising the step of receiving a switchover acknowledgement from the base station in response to said sending step.

57. The method of claim 44, further comprising the step of querying the base station to determine if the base station supports the at least two service protocols, wherein said querying step occurs between said determining step and said sending step.

58. The method of claim 44, wherein said switchover message includes a parameter indicating the service protocol.

59. The method of claim 44, wherein said switchover message includes a parameter indicating a frame number.

60. The method of claim 59, wherein said switching step occur after a frame having the frame number.

61. The method of claim 44, wherein the first error-detecting/correcting protocol is less robust than the second error-detecting/correcting protocol, and wherein said sending step sends the switchover message if the signal quality falls below the first predetermined threshold.

62. The method of claim 44, wherein the first error-detecting/correcting protocol is more robust than the second error-detecting/correcting protocol, and wherein said sending step sends the switchover message if the signal quality rises above the first predetermined threshold.

63. A base station configured to improve performance over wireless connections between the base station and a mobile station, the base station comprising:

at least two service protocols comprising a first error-detecting/correcting protocol and a second error-detecting/correcting protocol different from the first error-detecting/correcting protocol;

a link establishment module fur establishing a communication link with the mobile station using the first error-detecting/correcting protocol over a transmission channel;

a quality of service monitor for determining a signal quality of the transmission channel;

a transmitter for sending a switchover message to the mobile station to switch from the first error-detecting/correcting protocol to the second error-detecting/correcting protocol if the signal quality passes the first predetermined threshold; and

a protocol selector for switching to the second error-detecting/correcting.

64. The base station of claim 63, wherein said transmitter sends a switchover message to the mobile station to switch from the second error-detecting/correcting protocol to the first error-detecting/correcting protocol if the signal quality passes a second predetermined threshold, and wherein the protocol selector switches to the first error-detecting/correcting protocol.

65. The base station of claim 63 further comprising a query module for querying the mobile station to determine if the mobile station supports the at least two service protocols, wherein the switchover message is transmitted only if the mobile station supports the at least two service protocols.

66. The base station of claim 63, wherein said switchover message includes a parameter indicating the service protocol.

67. The base station of claim 63, wherein said switchover message includes a parameter indicating a frame number.

68. The base station of claim 67, wherein said switching step occur after a frame having the frame number.

69. The base station of claim 63, wherein the first error-detecting/correcting protocol is less robust than the second error-detecting/correcting protocol, and wherein the transmitter sends the switchover message if the signal quality falls below the first predetermined threshold.

70. The base station of claim 63, wherein the first error-detecting/correcting protocol is more robust than the second error-detecting/correcting protocol, and wherein the transmitter sends the switchover message if the signal quality rises above the first predetermined threshold.