Methods and apparatus for flexible spectrum allocation in communication systems

• US 20050207385A1
• Filed: 12/22/2004
• Published: 09/22/2005
• Est. Priority Date: 03/19/2004
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Gorokhov, Alexei, Agrawal, Avneesh
• Granted Patent: US 7,706,350 B2
• Time in Patent Office: Days
• US Class Current: 370/344
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0037 Inter-user or inter-terminal allocation
• CPC Class Codes: H04L 5/0042 intra-user or intra-terminal allocation
• CPC Class Codes: H04L 5/0046 Determination of how many bits are transmitted on different sub-channels
• CPC Class Codes: H04L 5/06 the signals being represented by different frequencies combined with time-division multiplexing H04L5/26

Abstract

The disclosed embodiments provide for methods and systems for flexibly allocating a shared frequency spectrum to a plurality of users, the spectrum may have a first number of segments, each segment having a second number of clusters associated with a certain sector/cell. In one aspect, a method for flexibly allocating a shared frequency spectrum to a plurality of users comprises the acts of fixedly assigning a first group of clusters to a first group of users, such that the first group of users stay fixed to the assigned clusters, and assigning a second group of clusters to a second group of users, such that the second group of users hop within the assigned clusters.

Claims

1. A method for allocating a frequency spectrum to a plurality of users, the spectrum having a first number of segments, each segment having a second number of clusters associated with a certain sector/cell, the method comprising:

assigning a first cluster of frequency sub-carriers within a first segment to a first user in a first sector/cell; and

assigning a second cluster of frequency sub-carriers within a second segment to a second user in a second sector/cell, such that the first cluster and the second cluster have different frequency sub-carrier assignment patterns.

2. The method of claim 1, wherein assigning a cluster within a segment to a user is based on channel quality of the user.

3. The method of claim 1, wherein the frequency spectrum comprises a shared bandwidth allocated to a plurality of users in an OFDMA communication system.

4. A method for allocating frequency spectrum to a plurality of users, the spectrum having a first number of segments, each segment having a second number of clusters associated with a certain sector, the method comprising:

assigning a cluster of frequency sub-carriers to each of a plurality of users in a first sector/cell; and

assigning a cluster of frequency sub-carriers to each of a plurality of users in a second sector/cell, such that each of the clusters assigned to the users in the first sector/cell has a different frequency sub-carrier assignment pattern with respect to each of the clusters assigned to the users in the second sector/cell.

5. The method of claim 4, wherein at least some of the clusters have noncontiguous sub-carrier assignment pattern.

6. A method for partitioning a frequency spectrum for allocation to a plurality of users, comprising:

partitioning a frequency spectrum into a first number of segments, each segment having a second number of frequency sub-carriers; and

partitioning a third number of frequency sub-carriers of a segment to a fourth number of clusters associated with a sector/cell, such that at least a fifth number of the clusters have non-overlapping frequency sub-carriers assignment patterns.

7. The method of claim 6, wherein each of the clusters associated with a first sector/cell has different frequency sub-carriers assignment pattern with respect to a sixth number of clusters associated with a second sector/cell.

8. The method of claim 6, wherein each of the clusters associated with a first sector/cell is different from each of the clusters associated with a second sector/cell in a same way.

9. The method of claim 6, wherein at least some of the clusters have noncontiguous sub-carrier frequency assignment pattern.

10. A method for flexibly allocating a frequency spectrum to a plurality of users, the spectrum having a first number of segments, each segment having a second number of clusters associated with a certain sector, the method comprising:

assigning a first group of clusters of frequency sub-carriers to a first group of users, the first group of users being fixedly assigned to the first group of clusters; and

assigning a second group of clusters of frequency sub-carriers to a second group users, the second group of users hopping within the second group of clusters.

11. The method of claim 10, wherein a user is identified by a flag indicating whether the user is scheduled for fixed or hopping assignment.

12. The method of claim 10, wherein a group of clusters is identified by a flag indicating whether the group of clusters is scheduled for fixed or hopping assignment.

13. The method of claim 10, further comprising reassigning a user from the first group of users to the second group of users, or a user from the second group of users to the first group of users, as at least one characteristic of such user is changed.

14. The method of claim 12, wherein the characteristic comprises mobility.

15. The method of claim 10, wherein each of the first and second groups of clusters may be reassigned to a different group of users, so that the first group of users may hop within the first group of clusters and the second group of users may stay with their respective assigned clusters within the second group of clusters.

16. A method for flexibly allocating a frequency spectrum to a plurality of users, the spectrum having a first number of segments, each segment having a second number of clusters associated with a certain sector/cell, the method comprising:

assigning a first number of clusters to each of a second number of groups; and

assigning a user to at least one cluster in each group.

17. The method of claim 16, wherein the user is scheduled to hop among the first number of clusters when the second number is smaller than the first number.

18. The method of claim 16, wherein the user is scheduled to either hop among the first number of clusters or stay fixed with the assigned clusters when the second number is smaller than the first number.

19. A computer-readable medium embodying means for implementing a method for allocating a frequency spectrum to a plurality of users, the spectrum having a first number of segments, each segment having a second number of clusters associated with a certain sector/cell, the method comprising:

assigning a first cluster of frequency sub-carriers within a first segment to a first user in a first sector/cell; and

assigning a second cluster of frequency sub-carriers within a second segment to a second user in a second sector/cell, such that the first cluster and the second cluster have different frequency sub-carrier assignment patterns.

20. The medium of claim 19, wherein assigning a cluster within a segment to a user is based on channel quality of the user.

21. The medium of claim 19, wherein the frequency spectrum comprises a shared bandwidth allocated to a plurality of users in an OFDMA communication system.

22. A computer-readable medium embodying means for implementing a method for allocating frequency spectrum to a plurality of users, the spectrum having a first number of segments, each segment having a second number of clusters associated with a certain sector, the method comprising:

assigning a cluster of frequency sub-carriers to each of a plurality of users in a first sector/cell; and

assigning a cluster of frequency sub-carriers to each of a plurality of users in a second sector/cell, such that each of the clusters assigned to the users in the first sector/cell has a different frequency sub-carrier assignment pattern with respect to each of the clusters assigned to the users in the second sector/cell.

23. The medium of claim 22, wherein at least some of the clusters have noncontiguous sub-carrier assignment pattern.

24. A computer-readable medium embodying means for implementing a method for partitioning a frequency spectrum for allocation to a plurality of users, comprising:

partitioning a frequency spectrum into a first number of segments, each segment having a second number of frequency sub-carriers; and

partitioning a third number of frequency sub-carriers of a segment to a fourth number of clusters associated with a sector/cell, such that at least a fifth number of the clusters have non-overlapping frequency sub-carriers assignment patterns.

25. The medium of claim 24, wherein each of the clusters associated with a first sector/cell has different frequency sub-carriers assignment pattern with respect to a sixth number of clusters associated with a second sector/cell.

26. The medium of claim 24, wherein each of the clusters associated with a first sector/cell is different from each of the clusters associated with a second sector/cell in a same way.

27. The medium of claim 24, wherein at least some of the clusters have noncontiguous sub-carrier frequency assignment pattern.

28. A computer-readable medium embodying means for implementing a method for flexibly allocating a frequency spectrum to a plurality of users, the spectrum having a first number of segments, each segment having a second number of clusters associated with a certain sector, the method comprising:

assigning a first group of clusters of frequency sub-carriers to a first group of users, the first group of users being fixedly assigned to the first group of clusters; and

assigning a second group of clusters of frequency sub-carriers to a second group users, the second group of users hopping within the second group of clusters.

29. The medium of claim 28, wherein a user is identified by a flag indicating whether the user is scheduled for fixed or hopping assignment.

30. The medium of claim 28, wherein a group of clusters is identified by a flag indicating whether the group of clusters is scheduled for fixed or hopping assignment.

31. The medium of claim 28, further comprising reassigning a user from the first group of users to the second group of users, or a user from the second group of users to the first group of users, as at least one characteristic of such user is changed.

32. The medium of claim 30, wherein the characteristic comprises mobility.

33. The medium of claim 28, wherein each of the first and second groups of clusters may be reassigned to a different group of users, so that the first group of users may hop within the first group of clusters and the second group of users may stay with their respective assigned clusters within the second group of clusters.

34. A computer-readable medium embodying means for implementing a method for flexibly allocating a frequency spectrum to a plurality of users, the spectrum having a first number of segments, each segment having a second number of clusters associated with a certain sector/cell, the method comprising:

assigning a first number of clusters to each of a second number of groups; and

assigning a user to at least one cluster in each group.

35. The medium of claim 34, wherein the user is scheduled to hop among the first number of clusters when the second number is smaller than the first number.

36. The medium of claim 34, wherein the user is scheduled to either hop among the first number of clusters or stay fixed with the assigned clusters when the second number is smaller than the first number.

37. An apparatus for allocating a frequency spectrum to a plurality of users, the spectrum having a first number of segments, each segment having a second number of clusters associated with a certain sector/cell, comprising:

means for assigning a first cluster of frequency sub-carriers within a first segment to a first user in a first sector/cell; and

means for assigning a second cluster of frequency sub-carriers within a second segment to a second user in a second sector/cell, such that the first cluster and the second cluster have different frequency sub-carrier assignment patterns.

38. The apparatus of claim 37, wherein assigning a cluster within a segment to a user is based on channel quality of the user.

39. The apparatus of claim 37, wherein the frequency spectrum comprises a shared bandwidth allocated to a plurality of users in an OFDMA communication system.

40. An apparatus for allocating frequency spectrum to a plurality of users, the spectrum having a first number of segments, each segment having a second number of clusters associated with a certain sector, comprising:

means for assigning a cluster of frequency sub-carriers to each of a plurality of users in a first sector/cell; and

means for assigning a cluster of frequency sub-carriers to each of a plurality of users in a second sector/cell, such that each of the clusters assigned to the users in the first sector/cell has a different frequency sub-carrier assignment pattern with respect to each of the clusters assigned to the users in the second sector/cell.

41. The apparatus of claim 40, wherein at least some of the clusters have noncontiguous sub-carrier assignment pattern.

42. An apparatus for partitioning a frequency spectrum for allocation to a plurality of users, comprising:

means for partitioning a frequency spectrum into a first number of segments, each segment having a second number of frequency sub-carriers; and

means for partitioning a third number of frequency sub-carriers of a segment to a fourth number of clusters associated with a sector/cell, such that at least a fifth number of the clusters have non-overlapping frequency sub-carriers assignment patterns.

43. The apparatus of claim 42, wherein each of the clusters associated with a first sector/cell has different frequency sub-carriers assignment pattern with respect to a sixth number of clusters associated with a second sector/cell.

44. The apparatus of claim 42, wherein each of the clusters associated with a first sector/cell is different from each of the clusters associated with a second sector/cell in a same way.

45. The apparatus of claim 42, wherein at least some of the clusters have noncontiguous sub-carrier frequency assignment pattern.

46. An apparatus for flexibly allocating a frequency spectrum to a plurality of users, the spectrum having a first number of segments, each segment having a second number of clusters associated with a certain sector, comprising:

means for assigning a first group of clusters of frequency sub-carriers to a first group of users, the first group of users being fixedly assigned to the first group of clusters; and

means for assigning a second group of clusters of frequency sub-carriers to a second group users, the second group of users hopping within the second group of clusters.

47. The apparatus of claim 46, further comprising means for indicating whether the user is scheduled for fixed or hopping assignment.

48. The apparatus of claim 46, further comprising means for indicating whether a group of clusters is scheduled for fixed or hopping assignment.

49. The apparatus of claim 46, further comprising means for reassigning a user from the first group of users to the second group of users, or a user from the second group of users to the first group of users, as at least one characteristic of such user is changed.

50. The apparatus of claim 48, wherein the characteristic comprises mobility.

51. The apparatus of claim 46, further comprising means for reassigning each of the first and second groups of clusters to a different group of users, so that the first group of users may hop within the first group of clusters and the second group of users may stay with their respective assigned clusters within the second group of clusters.

52. An apparatus for flexibly allocating a frequency spectrum to a plurality of users, the spectrum having a first number of segments, each segment having a second number of clusters associated with a certain sector/cell, comprising:

means for assigning a first number of clusters to each of a second number of groups; and

means for assigning a user to at least one cluster in each group.

53. The apparatus of claim 52, further comprising means for scheduling the user to hop among the first number of clusters when the second number is smaller than the first number.

54. The apparatus of claim 52, further comprising means for scheduling the user to either hop among the first number of clusters or stay fixed with the assigned clusters when the second number is smaller than the first number.

55. At least one processor programmed to execute a method for allocating a frequency spectrum to a plurality of users, the spectrum having a first number of segments, each segment having a second number of clusters associated with a certain sector/cell, the method comprising:

assigning a first cluster of frequency sub-carriers within a first segment to a first user in a first sector/cell; and

assigning a second cluster of frequency sub-carriers within a second segment to a second user in a second sector/cell, such that the first cluster and the second cluster have different frequency sub-carrier assignment patterns.

56. The processor of claim 55, wherein assigning a cluster within a segment to a user is based on channel quality of the user.

57. The processor of claim 55, wherein the frequency spectrum comprises a shared bandwidth allocated to a plurality of users in an OFDMA communication system.

58. At least one processor programmed to execute a method for allocating frequency spectrum to a plurality of users, the spectrum having a first number of segments, each segment having a second number of clusters associated with a certain sector, the method comprising:

assigning a cluster of frequency sub-carriers to each of a plurality of users in a first sector/cell; and

assigning a cluster of frequency sub-carriers to each of a plurality of users in a second sector/cell, such that each of the clusters assigned to the users in the first sector/cell has a different frequency sub-carrier assignment pattern with respect to each of the clusters assigned to the users in the second sector/cell.

59. The processor of claim 58, wherein at least some of the clusters have noncontiguous sub-carrier assignment pattern.

60. At least one processor programmed to execute a method for partitioning a frequency spectrum for allocation to a plurality of users, comprising:

partitioning a frequency spectrum into a first number of segments, each segment having a second number of frequency sub-carriers; and

partitioning a third number of frequency sub-carriers of a segment to a fourth number of clusters associated with a sector/cell, such that at least a fifth number of the clusters have non-overlapping frequency sub-carriers assignment patterns.

61. The processor of claim 60, wherein each of the clusters associated with a first sector/cell has different frequency sub-carriers assignment pattern with respect to a sixth number of clusters associated with a second sector/cell.

62. The processor of claim 60, wherein each of the clusters associated with a first sector/cell is different from each of the clusters associated with a second sector/cell in a same way.

63. The processor of claim 60, wherein at least some of the clusters have noncontiguous sub-carrier frequency assignment pattern.

64. At least one processor programmed to execute a method for flexibly allocating a frequency spectrum to a plurality of users, the spectrum having a first number of segments, each segment having a second number of clusters associated with a certain sector, the method comprising:

assigning a first group of clusters of frequency sub-carriers to a first group of users, the first group of users being fixedly assigned to the first group of clusters; and

assigning a second group of clusters of frequency sub-carriers to a second group users, the second group of users hopping within the second group of clusters.

65. The processor of claim 64, wherein a user is identified by a flag indicating whether the user is scheduled for fixed or hopping assignment.

66. The processor of claim 64, wherein a group of clusters is identified by a flag indicating whether the group of clusters is scheduled for fixed or hopping assignment.

67. The processor of claim 64, the method further comprising reassigning a user from the first group of users to the second group of users, or a user from the second group of users to the first group of users, as at least one characteristic of such user is changed.

68. The processor of claim 66, wherein the characteristic comprises mobility.

69. The processor of claim 64, wherein each of the first and second groups of clusters may be reassigned to a different group of users, so that the first group of users may hop within the first group of clusters and the second group of users may stay with their respective assigned clusters within the second group of clusters.

70. At least one processor programmed to execute a method for flexibly allocating a frequency spectrum to a plurality of users, the spectrum having a first number of segments, each segment having a second number of clusters associated with a certain sector/cell, the method comprising:

assigning a first number of clusters to each of a second number of groups; and

assigning a user to at least one cluster in each group.

71. The processor of claim 70, wherein the user is scheduled to hop among the first number of clusters when the second number is smaller than the first number.

72. The processor of claim 70, wherein the user is scheduled to either hop among the first number of clusters or stay fixed with the assigned clusters when the second number is smaller than the first number.