Enhanced reverse-link rate control in wireless communication

• US 6,741,862 B2
• Filed: 02/07/2001
• Issued: 05/25/2004
• Est. Priority Date: 02/07/2001
• Status: Expired due to Term

• Current Assignee: Ericsson Evdo, Inc. (CommScope Holding Company, Inc.)
• Original Assignee: Airvana Incorporated (CommScope Holding Company, Inc.)
• Inventors: Chung, Sae-Young, Kim, Dae-Young
• Primary Examiner(s): Vo, Nguyen T.
• Assistant Examiner(s): Smith, Sheila B.
• Application Number:
  US09/778,668
• Publication Number:
  US 20020151310A1
• Time in Patent Office: 1,203 Days
• Field of Search: 455/452, 455/453, 455/458, 455/226.3, 455/226.2, 455/63, 455/67.1, 455/67.4, 455/562, 370/252, 370/335, 370/458, 370/468, 370/328, 370/329, 370/229, 370/230, 370/232, 370/233, 370/234, 370/235, 375/225
• US Class Current: 455/452.1
• CPC Class Codes: H04B 1/707 using direct sequence modulation
• CPC Class Codes: H04B 1/7103 the interference being multiple access interference
• CPC Class Codes: H04B 2201/70701 featuring pilot assisted reception
• CPC Class Codes: H04B 2201/70703 using multiple or variable rates
• CPC Class Codes: H04B 2201/709709 Methods of preventing interference
• CPC Class Codes: H04L 1/0002 by adapting the transmission rate
• CPC Class Codes: H04L 1/0022 in which mode-switching is influenced by the user
• CPC Class Codes: H04L 1/0025 Transmission of mode-switching indication
• CPC Class Codes: H04L 2001/0092 Error control systems characterised by the topology of the transmission link

Abstract

By controlling reverse rates among mobile stations to reduce reverse-link interference, reverse-link throughput can be increased.

Claims

1. A method comprising

determining a forward-link data rate at a mobile device at which the mobile device desires to receive its forward-link data packets from a base station,

transmitting information conveying the forward-link data rate from the mobile station to the base station,

determining a maximum reverse data rate at the base station based on the forward-link data rate,

transmitting information conveying the maximum reverse data rate from the base station to the mobile device,

determining at the mobile station its operational reverse rate between zero and the maximum reverse data rate, and

transmitting data packets by the mobile station at the determined operational reverse rate.

2. The method of claim 1 further comprising averaging the forward-link data rate over a certain period of time, and

wherein determining the maximum reverse data rate further comprises determining the maximum reverse data rate in a sector of the base station using the averaged forward-link data.

3. The method of claim 1 in which the transmitted information from the base station to the mobile device comprises one or more rate control bits from the base station to the mobile device.

4. The method of claim 3 in which the one or more reverse rate control bits comprise a first bit configuration indicating an increase to a maximum reverse data rate and a second bit configuration indicating a decrease to the maximum reverse data rate.

5. The method of claim 4 in which the one or more reverse rate control bits further comprise a third bit configuration indicating no change in the maximum reverse data rate.

6. The method of claim 4 further comprising transmitting, by the mobile device, data at a rate between zero and the maximum reverse data rate based on the one or more reverse rate control bits received from the base station.

7. The method of claim 1 wherein determining the maximum reverse data rate further comprises determining the maximum reverse rate so that an aggregate rate associated with all mobile devices in one or more sectors is maximized.

8. The method of claim 1 wherein determining the maximum reverse data rate further comprises determining the maximum reverse rate of the mobile device in accord with a condition.

9. The method of claim 8 in which the condition includes fairness among mobile devices.

10. The method of claim 9 in which the fairness is defined as a ratio of highest and lowest user throughputs.

11. The method of claim 1 in which the base station has one or more sectors.

12. The method of claim 1 wherein determining the operational reverse rate further comprises determining the operational reverse rate based on a current transmission rate of the mobile device.

13. The method of claim 1 wherein determining the operational reverse rate further comprises determining the operational reverse rate based on an amount of data to transmit at the mobile device.

14. The method of claim 1 wherein determining the operational reverse rate further comprises determining the operational reverse rate based on transition probabilities to increase or decrease the rate and on sector rate control information received from one or more base stations.

15. The method of claim 14 in which values of the transition probabilities are transmitted from one or more base stations.

16. The method of claim 14 in which the sector rate control information is defined per sector and comprises a first bit configuration indicating a probabilistic increase to the mobile device'"'"'s operational reverse rate and a second bit configuration indicating a probabilistic decrease to the mobile device'"'"'s operational reverse rate.

17. The method of claim 1 wherein the base station is a first base station, the method further comprising

receiving, at one or more base stations other than the first base station, the information conveying the forward-link data rate and a requested reverse data rate from the mobile station;

and

relaying the information to the first base station.

18. A method comprising

determining a maximum reverse data rate based on an estimated amount of interference a mobile device is causing to one or more sectors other than the sectors serving the mobile device,

transmitting reverse rate information conveying the maximum reverse data rate between a base station and the mobile device, the base station including one or more sectors, and

transmitting sector rate control information from the one or more sectors to all mobile devices in that respective sector,

determining an operational reverse rate at the mobile station between zero and the maximum rate based on the sector rate control information, and

transmitting data packets by the mobile station at the determined operational reverse rate without further consulting the base station.

19. The method of claim 18 wherein determining the maximum reverse data rate further comprises determining the estimated amount of interference based on a forward-link SIR for the mobile device.

20. The method of claim 19 further comprising averaging the forward-link SIR over a period of time.

21. The method of claim 19 further comprising determining the forward-link SIR based on received pilot power at the mobile device from one or more sectors.

22. The method of claim 19 further comprising determining the forward-link SIR based on total power received at the mobile device.

23. The method of claim 18 wherein determining the maximum reverse rate further comprises determining the maximum reverse rate based on a queue status of the mobile device.

24. The method of claim 18 wherein determining the maximum reverse rate further comprises determining the maximum reverse rate based on a status of the sector in which the mobile device is operating.

25. The method of claim 24 in which the status of the sector is associated with a number of mobile devices.

26. The method of claim 24 in which the status of the sector is associated with a set of reverse rates of other devices operating in the sector.

27. The method of claim 18 wherein transmitting the reverse rate information further comprises transmitting the reverse rate information comprising one or more rate control bit or bits from one or more base stations to the mobile device.

28. The method of claim 27 in which the one or more reverse rate control bit or bits comprise a first bit configuration indicating an increase to the maximum reverse rate and a second bit configuration indicating a decrease to the maximum reverse rate.

29. The method of claim 28 in which the one or more reverse rate control bit or bits further comprises a third bit configuration indicating no change in the maximum reverse rate.

30. The method of claim 27

wherein determining its operational reverse rate further comprises determining, by the mobile device, its operational reverse rate based on the rate control bits received from one or more base stations, the method further comprising,

storing, by the mobile device, its operational reverse rate.

31. The method of claim 18 wherein determining the operational reverse rate further comprises determining the operational reverse rate based on a current rate of the mobile device.

32. The method of claim 18 wherein determining the operational reverse rate further comprises determining the operational reverse rate based on an amount of data to transmit at the mobile device.

33. The method of claim 18 wherein determining the operational reverse rate further comprises determining the operational reverse rate based on transition probabilities to increase or decrease the rate and on sector rate control information received from one or more base stations.

34. The method of claim 33 further comprising transmitting values of the transition probabilities from one or more base stations.

35. The method of claim 34 wherein determining the maximum reverse rate further comprises determining the maximum reverse rate of the mobile device so that an aggregate rate associated with all mobile devices in one or more sectors is maximized.

36. The method of claim 34 wherein determining the maximum reverse data rate further comprises determining the maximum reverse data rate of the mobile device in accord with a condition.

37. The method of claim 36 in which the condition includes fairness among mobile devices.

38. The method of claim 37 in which the fairness is defined as a ratio of highest and lowest user throughputs.

39. A method comprising,

determining a forward-link data rate at a mobile device at which the mobile device desires to receive its forward-link data packets from a base station,

determining a requested reverse data rate at the mobile station at which the mobile device desires to transmit its reverse-link data packets to the base station,

transmitting information conveying the forward-link data rate and the requested reverse data rate from the mobile station to the base station,

determining at the base station a reverse data rate between zero and the requested reverse data rate based on the forward-link data rate information,

transmitting information conveying the determined reverse data rate from the base station to the mobile device, and

transmitting data packets by the mobile station at the determined reverse rate.

40. The method of claim 39 wherein the base station comprises one or more sectors.

41. The method of claim 39 wherein the base station is a first base station, the method further comprising

receiving, at one or more base stations other than the first base station, the information conveying the forward-link data rate and the requested reverse data rate from the mobile station;

and

relaying the information to the first base station.

42. The method of claim 39 wherein one or more base stations including the base station receive the reverse-link data packets from the mobile station.

43. The method of claim 39 further comprising averaging the requested forward-link data rate over a certain period of time, and

wherein determining at the base station a reverse data further comprises determining the reverse data rate at the base station using the averaged forward-link data rate.

44. The method of claim 39 wherein determining the requested reverse rate further comprises determining the requested reverse rate at the mobile device based on a queue status of the mobile device.

45. The method of claim 39 wherein determining the requested reverse rate further comprises determining the requested reverse rate at the mobile device based on a status of a sector in which the mobile device is operating.

46. The method of claim 45 in which the status of the sector is associated with a number of mobile devices.

47. The method of claim 46 in which the status of the sector is associated with a set of reverse rates of other devices operating in the sector.

48. A method comprising

determining a forward-link data rate at a mobile device at which the mobile device desires to receive its forward-link data packets from a base station,

transmitting information conveying the desired forward-link data rate from the mobile station to the base station,

determining at the base station a reverse data rate based on the desired forward-link data rate information,

transmitting information conveying the determined reverse data rate from the base station to the mobile device, and

transmitting data packets by the mobile station at the determined rate.

49. The method of claim 48 wherein the base station comprises one or more sectors.

50. The method of claim 48 wherein the base station is a first base station, the method further comprising

receiving, at one or more base stations other than the first base station, the information conveying the forward-link data rate and the requested reverse data rate from the mobile station;

and

relaying the information to the first base station.

51. The method of claim 48 wherein one or more base stations including the base station receive the reverse-link data packets from the mobile station.

52. The method of claim 48 further comprising averaging the requested forward-link data rate over a certain period of time, and

wherein determining the reverse data rate further comprises determining the reverse data rate at the base station using the averaged forward-link data rate.