Downlink load sharing by nulling, beam steering and beam selection

• US 20030095065A1
• Filed: 06/28/2002
• Published: 05/22/2003
• Est. Priority Date: 11/20/2001
• Status: Active Grant

• Current Assignee: Optis Cellular Technology LLC (Brevet Capital)
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Ericson, Marten, Goransson, Bo, Hagerman, Bo, Petersson, Sven
• Granted Patent: US 6,667,712 B2
• Time in Patent Office: Days
• US Class Current: 342/354
• CPC Class Codes: H01Q 1/246 specially adapted for base stations
• CPC Class Codes: H01Q 3/2605 Array of radiating elements provided with a feedback control over the element weights, e.g. adaptive arrays
• CPC Class Codes: H04W 16/28 using beam steering
• CPC Class Codes: H04W 36/06 Reselecting a communication resource in the serving access point

Abstract

The beam pattern associated with a multi-beam antenna array is adjusted if a first beam of the beam pattern is overloaded. A lobe of a second beam of the beam pattern can be steered away from a main lobe of the first beam. Also, if a user is located in an area covered by a second beam which is adjacent to the first beam, a third beam of the beam pattern can be selected for effectuating communication with the user. If a user is located in an area covered by the first beam, another beam of the beam pattern can be selected for effectuating communication with the user.

Claims

1. A method of controlling a beam pattern associated with a multi-beam antenna array, comprising:

receiving information which indicates that a first beam of the beam pattern is overloaded; and

in response to said information, steering a lobe of a second beam of the beam pattern away from a main lobe of the first beam.

2. The method of claim 1, wherein the lobe of the second beam is a main lobe of the second beam.

3. The method of claim 2, including receiving information indicative of whether the main lobe of the second beam has more available communication capacity than the main lobe of the first beam, and said steering step including steering the main lobe of the second beam away from the main lobe of the first beam only if the information indicates that the main lobe of the second beam has more available communication capacity than the main lobe of the first beam.

4. The method of claim 3, wherein, before said steering step, the main lobe of the second beam spatially overlaps the main lobe of the first beam.

5. The method of claim 2, including steering a null of the second beam toward the main lobe of the first beam.

6. The method of claim 5, wherein said null steering step includes steering a sidelobe of the second beam away from the first beam.

7. The method of claim 2, wherein, before said steering step, the main lobe of the second beam spatially overlaps the main lobe of the first beam.

8. The method of claim 1, wherein the lobe of the second beam is a sidelobe of the second beam.

9. The method of claim 8, wherein said steering step includes steering a null of the second beam toward the main lobe of the first beam.

10. The method of claim 9, wherein said steering step includes steering the sidelobe of the second beam toward a further beam of the beam pattern that has more available communication capacity than the main lobe of the first beam.

11. The method of claim 8, wherein said steering step includes steering the sidelobe of the second beam toward a further beam of the beam pattern that has more available communication capacity than the main lobe of the first beam.

12. The method of claim 8, including determining that no beam in the beam pattern both spatially overlaps the main lobe of the first beam and has more available communication capacity than the main lobe of the first beam.

13. The method of claim 1, wherein said steering step includes steering a null of the second beam toward the main lobe of the first beam.

14. The method of claim 13, including determining that no beam in the beam pattern both spatially overlaps the main lobe of the first beam and has more available communication capacity than the main lobe of the first beam.

15. The method of claim 14, wherein the lobe of the second beam is a sidelobe of the second beam.

16. The method of claim 15, wherein said steering step includes steering the sidelobe of the second beam toward a further beam of the beam pattern that has more available communication capacity than the main lobe of the first beam.

17. A method of managing loading in a beam pattern associated with a multi-beam antenna array, comprising:

receiving first information which indicates that a first beam of the beam pattern is overloaded;

receiving second information which indicates that a user is located in an area covered by a second beam which is adjacent to the first beam in the beam pattern; and

in response to said first and second information, selecting a third beam of the beam pattern for effectuating communication with the user.

18. The method of claim 17, wherein the third beam has more available communication capacity than the first beam.

19. The method of Clam 17, wherein the user causes more interference to another user than said another user causes to the first-mentioned user.

20. The method of claim 19, wherein the first-mentioned user is a user of one of a video service, a web browsing service, a file transfer service and a speech service.

21. A multi-beam antenna apparatus, comprising:

a steerable antenna array for producing a beam pattern;

an input for receiving information which indicates that a first beam of the beam pattern is overloaded; and

a steering apparatus coupled to said input and said antenna array, said steering apparatus cooperable with said antenna array in response to said information for steering a lobe of a second beam of the beam pattern away from a main lobe of the first beam.

22. The apparatus of claim 21, wherein the lobe of the second beam is a main lobe of the second beam.

23. The apparatus of claim 22, wherein said input is further for receiving information indicative of whether the main lobe of the second beam has more available communication capacity than the main lobe of the first beam, said steering apparatus cooperable with said antenna array for steering the main lobe of the second beam away from the main lobe of the first beam only if said last-mentioned information indicates that the main lobe of the second beam has more available communication capacity than the main lobe of the first beam.

24. The apparatus of claim 22, wherein said steering apparatus is cooperable with said antenna array in response to said information for steering a null of the second beam toward the main lobe of the first beam.

25. The apparatus of claim 24, wherein said steering apparatus is cooperable with said antenna array in response to said information for steering a sidelobe of the second beam away from the first beam.

26. The apparatus of claim 22, wherein, before said steering operation, the main lobe of the second beam spatially overlaps the main lobe of the first beam.

27. The apparatus of claim 21, wherein the lobe of the second beam is a sidelobe of the second beam.

28. The apparatus of claim 27, wherein said steering apparatus is cooperable with said antenna array in response to said information for steering a null of the second beam toward the main lobe of the first beam.

29. The apparatus of claim 28, wherein said steering apparatus is cooperable with said antenna array in response to said information for steering the sidelobe of the second beam toward a further beam of the beam pattern that has more available communication capacity than the main lobe of the first beam.

30. The apparatus of claim 27, wherein said steering apparatus is cooperable with said antenna array in response to said information for steering the sidelobe of the second beam toward a further beam of the beam pattern that has more available communication capacity than the main lobe of the first beam.

31. The apparatus of claim 21, provided in one of a CDMA base station and a WCDMA base station.

32. An apparatus for managing loading in a beam pattern associated with a multi-beam antenna array, comprising:

an input for receiving first information which indicates that a first beam of the beam pattern is overloaded, and for receiving second information which indicates that a user is located in an area covered by a second beam which is adjacent to the first beam in the beam pattern; and

a selector coupled to said input and responsive to said first and second information for selecting a third beam of the beam pattern for effectuating communication with the user.

33. The apparatus of claim 32, wherein the third beam has more available communication capacity than the first beam.

34. The apparatus of claim 32, wherein the user causes more interference to another user than said another user causes to the first-mentioned user.

35. The apparatus of claim 34, wherein the user is a user of one of a video service, a web browsing service, a file transfer service and a speech service.

36. The apparatus of claim 32, provided in one of a CDMA base station and a WCDMA base station.

37. The apparatus of claim 32, wherein the multi-beam antenna array is a fixed beam (FB) array.

38. A method of managing loading in a beam pattern associated with a multi-beam antenna array, comprising:

receiving information which indicates that a first beam of the beam pattern is overloaded and that a user is located in an area covered by the first beam; and

in response to said information, selecting for communication with the user a second beam of the beam pattern which is adjacent to the first beam in the beam pattern.

39. The method of claim 38, wherein the second beam has more available communication capacity than the first beam.

40. The method of claim 38, wherein the user causes more interference to another user than said another user causes to the first-mentioned user.

41. The method of claim 40, wherein the first-mentioned user is a user of one of a video service, a web browsing service, a file transfer service and a speech service.

42. An apparatus for managing loading in a beam pattern associated with a multi-beam antenna array, comprising:

an input for receiving information which indicates that a first beam of the beam pattern is overloaded and that a user is located in an area covered by the first beam; and

a selector coupled to said input and operable in response to said information to select for communication with the user a second beam of the beam pattern which is adjacent to the first beam in the beam pattern.

43. The apparatus of claim 42, wherein the second beam has more available communication capacity than the first beam.

44. The apparatus of claim 42, wherein the user causes more interference to another user than said another user causes to the first-mentioned user.

45. The apparatus of claim 44, wherein the user is a user of one of a video service, a web browsing service, a file transfer service and a speech service.

46. The apparatus of claim 42, provided in one of a CDMA base station and a WCDMA base station.

47. The apparatus of claim 42, wherein the multi-beam antenna array is a fixed beam (FB) array.