INTERFERENCE REDUCTION REQUEST IN A WIRELESS COMMUNICATION SYSTEM

• US 20090197538A1
• Filed: 10/30/2008
• Published: 08/06/2009
• Est. Priority Date: 02/01/2008
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Sampath, Ashwin, Gorokhov, Alexei, Bhushan, Naga, Palanki, Ravi, Agrawal, Avneesh, Khandekar, Aamod, Borran, Mohammad J., Horn, Gavin B.
• Granted Patent: US 8,843,069 B2
• Time in Patent Office: Days
• US Class Current: 455/63.1
• CPC Class Codes: H04B 17/382 for resource allocation, admission control or handover
• CPC Class Codes: H04B 7/0617 for beam forming
• CPC Class Codes: H04W 52/243 taking into account interferences
• CPC Class Codes: H04W 52/247 where the output power of a terminal is based on a path parameter sent by another terminal

Abstract

Techniques for transmitting data with short-term interference mitigation in a wireless communication system are described. In one design, a first station (e.g., a base station or a terminal) may send a first message to at least one interfering station to request reduction of interference on at least one resource. The first station may send the first message in anticipation of receiving data on the at least one resource. An interfering station may receive the first message from the first station and may reduce interference on the at least one resource by reducing its transmit power and/or by steering its power in a direction different from the first station. The first station may thereafter receive data from a second station on the at least one resource. The techniques may be used for data transmission on the forward and reverse links.

Claims

1. A method for wireless communication, comprising:

sending a first message from a first station to at least one interfering station to request reduction of interference on at least one resource, the first message being sent in anticipation of data being received by the first station on the at least one resource; and

receiving a data transmission on the at least one resource from a second station.

2. The method of claim 1, wherein the first station is a terminal and the second station is a base station, and wherein the data is received on forward link.

3. The method of claim 1, wherein the first station is a base station and the second station is a terminal, and wherein the data is received on reverse link.

4. The method of claim 1, further comprising:

generating the first message to include information identifying the at least one resource.

5. The method of claim 1, further comprising:

generating the first message to include an indication of priority of the request.

6. The method of claim 1, further comprising:

generating the first message to include a target reduction in transmit power of an interfering station.

7. The method of claim 1, further comprising:

generating the first message to include a target interference level for the first station.

8. The method of claim 1, further comprising:

generating the first message to include spatial information usable by an interfering station to steer power in a direction different from the first station.

9. The method of claim 1, wherein the sending the first message comprises

sending the first message as a broadcast message to all of the at least one interfering station.

10. The method of claim 1, wherein the sending the first message comprises

sending the first message as a unicast message to each of the at least one interfering station.

11. The method of claim 1, further comprising:

receiving a second message to trigger short-term interference mitigation from the second station, wherein the first message is sent in response to receiving the second message.

12. The method of claim 1, further comprising:

receiving a resource request from the second station, wherein the first message is sent in response to receiving the resource request.

13. An apparatus for wireless communication, comprising:

at least one processor configured to send a first message from a first station to at least one interfering station to request reduction of interference on at least one resource, the first message being sent in anticipation of data being received by the first station on the at least one resource, and to receive a data transmission on the at least one resource from a second station.

14. The apparatus of claim 13, wherein the at least one processor is configured to generate the first message to include at least one of information identifying the at least one resource, an indication of priority of the request, a target interference level for the first station, a target reduction in transmit power of an interfering station, and spatial information usable by an interfering station to steer power in a direction different from the first station.

15. The apparatus of claim 13, wherein the at least one processor is configured to receive a second message to trigger short-term interference mitigation from the second station, and to send the first message in response to receiving the second message.

16. The apparatus of claim 13, wherein the at least one processor is configured to receive a resource request from the second station and to send the first message in response to receiving the resource request.

17. An apparatus for wireless communication, comprising:

means for sending a first message from a first station to at least one interfering station to request reduction of interference on at least one resource, the first message being sent in anticipation of data being received by the first station on the at least one resource; and

means for receiving a data transmission on the at least one resource from a second station.

18. The apparatus of claim 17, further comprising:

means for generating the first message to include at least one of information identifying the at least one resource, an indication of priority of the request, a target interference level for the first station, a target reduction in transmit power of an interfering station, and spatial information usable by an interfering station to steer power in a direction different from the first station.

19. The apparatus of claim 17, further comprising:

means for receiving a second message to trigger short-term interference mitigation from the second station, wherein the first message is sent in response to receiving the second message.

20. The apparatus of claim 17, further comprising:

means for receiving a resource request from the second station, and wherein the first message is sent in response to receiving the resource request.

21. A computer program product, comprising:

a computer-readable medium comprising;

code for causing at least one computer to send a first message from a first station to at least one interfering station to request reduction of interference on at least one resource, the first message being sent in anticipation of data being received by the first station on the at least one resource, and

code for causing the at least one computer to receive a data transmission on the at least one resource from a second station.

22. A method for wireless communication, comprising:

receiving a first message sent by a first station to request reduction of interference on at least one resource, the first message being sent by the first station in anticipation of data being received by the first station on the at least one resource; and

reducing interference on the at least one resource by a second station.

23. The method of claim 22, further comprising:

obtaining priority of the request from the first message; and

determining whether to grant or dismiss the request based on the priority of the request.

24. The method of claim 22, wherein the reducing interference comprises

obtaining a target reduction in transmit power from the first message, and

reducing transmit power of the second station on the at least one resource by an amount determined based on the target reduction in transmit power.

25. The method of claim 22, wherein the reducing interference comprises

obtaining spatial information from the first message, and

performing preceding based on the spatial information to steer power of the second station in a direction different from the first station.

26. An apparatus for wireless communication, comprising:

at least one processor configured to receive a first message sent by a first station to request reduction of interference on at least one resource, the first message being sent by the first station in anticipation of data being received by the first station on the at least one resource, and to reduce interference on the at least one resource by a second station.

27. The apparatus of claim 26, wherein the at least one processor is configured to obtain priority of the request from the first message and to determine whether to grant or dismiss the request based on the priority of the request.

28. The apparatus of claim 26, wherein the at least one processor is configured to obtain a target reduction in transmit power from the first message and to reduce transmit power of the second station on the at least one resource by an amount determined based on the target reduction in transmit power.

29. The apparatus of claim 26, wherein the at least one processor is configured to obtain spatial information from the first message and to perform preceding based on the spatial information to steer power of the second station in a direction different from the first station.

30. A method for wireless communication, comprising:

sending a first message from a terminal to request at least one interfering base station to reduce interference on at least one resource, the first message being sent in anticipation of data being received by the terminal on the at least one resource; and

receiving a data transmission on the at least one resource from a serving base station.

31. The method of claim 30, further comprising:

receiving a second message triggering short-term interference mitigation from the serving base station, wherein the first message is sent in response to receiving the second message.

32. The method of claim 30, further comprising:

receiving at least one transmission or pilot from the at least one interfering base station, each transmission or pilot indicating a transmit power level to be used on the at least one resource by a corresponding interfering base station.

33. The method of claim 32, further comprising:

estimating channel quality of the at least one resource based on the at least one transmission or pilot from the at least one interfering base station; and

sending information indicative of the channel quality of the at least one resource to the serving base station.

34. The method of claim 30, further comprising:

receiving at least one pilot on the at least one resource from the at least one interfering base station in a first time period, wherein the data transmission is received on the at least one resource in a second time period later than the first time period.

35. An apparatus for wireless communication, comprising:

at least one processor configured to send a first message from a terminal to request at least one interfering base station to reduce interference on at least one resource, the first message being sent in anticipation of data being received by the terminal on the at least one resource, and to receive a data transmission on the at least one resource from a serving base station.

36. The apparatus of claim 35, wherein the at least one processor is configured to receive a second message triggering short-term interference mitigation from the serving base station, and to send the first message in response to receiving the second message.

37. The apparatus of claim 35, wherein the at least one processor is configured to receive at least one pilot from the at least one interfering base station, each pilot being sent at a transmit power level to be used on the at least one resource by a corresponding interfering base station, to estimate channel quality of the at least one resource based on the at least one pilot from the at least one interfering base station, and to send information indicative of the channel quality of the at least one resource to the serving base station.

38. A method for wireless communication, comprising:

sending a first message from a base station to request at least one interfering terminal to reduce interference on at least one resource, the first message being sent in anticipation of data being received by the base station on the at least one resource; and

receiving a data transmission on the at least one resource from a terminal.

39. The method of claim 38, further comprising:

sending a second message to request transmit capability of the terminal for the at least one resource;

receiving a transmission comprising the transmit capability of the terminal for the at least one resource; and

scheduling the terminal for the data transmission based on the transmit capability of the terminal for the at least one resource.

40. The method of claim 38, further comprising:

receiving pilots from the terminal and the at least one interfering terminal, each pilot being transmitted by a corresponding terminal at a maximum transmit power level usable for the at least one resource;

estimating channel quality of the at least one resource based on the received pilots;

selecting a modulation and coding scheme based on the estimated channel quality of the at least one resource; and

sending a resource grant comprising the modulation and coding scheme to the terminal.

41. An apparatus for wireless communication, comprising:

at least one processor configured to send a first message from a base station to request at least one interfering terminal to reduce interference on at least one resource, the first message being sent in anticipation of data being received by the base station on the at least one resource, and to receive a data transmission on the at least one resource from a terminal.

42. The apparatus of claim 41, wherein the at least one processor is configured to send a second message to request transmit capability of the terminal for the at least one resource, to receive a transmission comprising the transmit capability of the terminal for the at least one resource, and to schedule the terminal for the data transmission based on the transmit capability of the terminal for the at least one resource.

43. The apparatus of claim 41, wherein the at least one processor is configured to receive pilots from the terminal and the at least one interfering terminal, each pilot being transmitted by a corresponding terminal at a maximum transmit power level usable for the at least one resource, to estimate channel quality of the at least one resource based on the received pilots, to select a modulation and coding scheme based on the estimated channel quality of the at least one resource, and to send a resource grant comprising the modulation and coding scheme to the terminal.