METHODS AND APPARATUSES FOR SCHEDULING UPLINK REQUEST SPATIAL DIVISION MULTIPLE ACCESS (RSDMA) MESSAGES IN AN SDMA CAPABLE WIRELESS LAN

• US 20100220679A1
• Filed: 02/25/2010
• Published: 09/02/2010
• Est. Priority Date: 02/27/2009
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: ABRAHAM, SANTOSH P., Sridhara, Vinay
• Granted Patent: US 8,989,106 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04W 74/06 using polling
• CPC Class Codes: H04W 74/0808 using carrier sensing, e.g. carrier sense multiple access [CSMA]
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

An apparatus for wireless communications, including a processing system configured to receive requests for a spatial division multiplexed transmission from a plurality of nodes over a multiple access medium; and initiate the spatial division multiplexed transmission based on a metric related to one or more of the nodes, is disclosed. Another apparatus for wireless communications, including a processing system configured to generate data belonging to an access class having contention parameters; and precode at least a portion of the data for transmission over a spatial stream and enter into post backoff following the spatial stream transmission, is also disclosed. Methods for using the apparatuses are also disclosed.

Claims

1. An apparatus for wireless communications, comprising:

a processing system configured to;

receive requests for a spatial division multiplexed transmission from a plurality of nodes over a multiple access medium; and

initiate the spatial division multiplexed transmission based on a metric related to one or more of the nodes.

2. The apparatus of claim 1, wherein the processing system is further configured to allocate a plurality of slots for receiving requests for transmission from the plurality of nodes.

3. The apparatus of claim 2, wherein the allocation comprises a bitmap.

4. The apparatus of claim 3, wherein each bit in the bitmap is associated with a node in the plurality of nodes and comprises an indication that the node will request transmission.

5. The apparatus of claim 1 wherein the metric comprises an amount of data to be transmitted by each of the one or more nodes.

6. The apparatus of claim 5 wherein the processing system is further configured to determine the metric based on the amount of data stored in a buffer at each of the one or more nodes.

7. The apparatus of claim 1 wherein the metric comprises channel state information for each of the one or more nodes.

8. The apparatus of claim 1 wherein the metric comprises at least one of a quality of service or priority-based requirement for each of the one or more nodes.

9. The apparatus of claim 1 wherein the processing system is further configured to initiate the spatial division multiplexed transmission by contending for access to the medium to broadcast a message.

10. The apparatus of claim 9 wherein the message identifies the nodes for the spatial division multiplexed transmission.

11. The apparatus of claim 9 wherein data to be transmitted by each of the nodes belongs to an access class comprising contention parameters, and wherein the processing system is further configured to contend for access to the medium using the contention parameters of the access class.

12. The apparatus of claim 11 wherein the contention parameters comprise a minimum contention window size, and wherein the processing system is further configured to contend for access to the medium using a contention window size that is less than the minimum contention window size for the access class.

13. The apparatus of claim 12 wherein the minimum contention window size is equal to a number based on the minimum contention window size for the access class divided by the number of the nodes with data to transmit.

14. The apparatus of claim 9 wherein the processing system is further configured to receive a request to send data from each of the nodes in response to the message.

15. The apparatus of claim 1 wherein the processing system is further configured to broadcast a message to allocate spatial streams to each of the nodes.

16. The apparatus of claim 15 wherein the processing system is further configured to receive a sounding frame from each of the nodes to compute channel state information to enable the processing system to separate data from the spatial streams.

17. The apparatus of claim 15 wherein the processing system is further configured to receive data from each of the nodes on the allocated spatial streams.

18. The apparatus of claim 17 wherein the processing system is further configured to transmit an acknowledgement in response to receiving the data from each of the nodes on the allocated spatial streams.

19. The apparatus of claim 1 wherein the processing system is further configured to signal other nodes not involved in the spatial division multiplexed transmission to defer their transmissions for the duration of the spatial division multiplexed transmission.

20. The apparatus of claim 1 wherein the processing system is further configured to signal other nodes not involved in the spatial division multiplexed transmission in compliance with legacy nodes that do not support spatial division multiplexed transmission.

21. An apparatus for wireless communications, comprising:

means for receiving requests for a spatial division multiplexed transmission from a plurality of nodes over a multiple access medium; and

means for initiating the spatial division multiplexed transmission based on a metric related to one or more of the nodes.

22. The apparatus of claim 21, further comprising means for allocating a plurality of slots for receiving requests for transmission from the plurality of nodes.

23. The apparatus of claim 22, wherein the allocation comprises a bitmap.

24. The apparatus of claim 23, wherein each bit in the bitmap is associated with a node in the plurality of nodes and comprises an indication that the node will request transmission.

25. The apparatus of claim 21 wherein the metric comprises an amount of data to be transmitted by each of the one or more nodes.

26. The apparatus of claim 25 further comprising means for determining the metric based the amount of data stored in a buffer at each of the one or more nodes.

27. The apparatus of claim 21 wherein the metric comprises channel state information for each of the one or more nodes.

28. The apparatus of claim 21 wherein the metric comprises at least one of a quality of service or priority-based requirement for each of the one or more nodes.

29. The apparatus of claim 21 wherein the means for initiating the spatial division multiplexed transmission comprises means for contending for access to the medium to broadcast a message.

30. The apparatus of claim 29 wherein the message identifies the nodes for the spatial division multiplexed transmission.

31. The apparatus of claim 29 wherein data to be transmitted by each of the nodes belongs to an access class comprising contention parameters, and wherein the means for contending for access to the medium is configured to use the contention parameters of the access class.

32. The apparatus of claim 31 wherein the contention parameters comprise a minimum contention window size, and the means for contending for access to the medium comprises means for contending for access to the medium using a contention window size that is less than the minimum contention window size for the access class.

33. The apparatus of claim 32 wherein the minimum contention window size is equal to a number based on the minimum contention window size for the access class divided by the number of the nodes with data to transmit.

34. The apparatus of claim 29 further comprising means for receiving a request to send data from each of the nodes in response to the message.

35. The apparatus of claim 21, further comprising means for broadcasting a message to allocate spatial streams to each of the nodes.

36. The apparatus of claim 35 further comprising means for receiving a sounding frame from each of the nodes to compute channel state information to enable the data to be separated from the spatial streams.

37. The apparatus of claim 35 further comprising means for receiving data from each of the nodes on the allocated spatial streams.

38. The apparatus of claim 37 further comprising means for transmitting an acknowledgement in response to receiving the data from each of the nodes on the allocated spatial streams.

39. The apparatus of claim 21 further comprising means for signaling other nodes not involved in the spatial division multiplexed transmission to defer transmissions for the duration of the spatial division multiplexed transmission.

40. The apparatus of claim 21 further comprising means for signal other nodes not involved in the spatial division multiplexed transmission in compliance with legacy nodes that do not support spatial division multiplexed transmission.

41. A method for wireless communications, comprising:

receiving requests for a spatial division multiplexed transmission from a plurality of nodes over a multiple access medium; and

initiating the spatial division multiplexed transmission based on a metric related to one or more of the nodes.

42. The method of claim 41, further comprising allocating a plurality of slots for receiving requests for transmission from the plurality of nodes.

43. The method of claim 42, wherein the allocation comprises a bitmap.

44. The method of claim 43, wherein each bit in the bitmap is associated with a node in the plurality of nodes and comprises an indication that the node will request transmission.

45. The method of claim 41 wherein the metric comprises an amount of data to be transmitted by each of the one or more nodes.

46. The method of claim 45 further comprising determining the metric based the amount of data stored in a buffer at each of the one or more nodes.

47. The method of claim 41 wherein the metric comprises channel state information for each of the one or more nodes.

48. The method of claim 41 wherein the metric comprises at least one of a quality of service or priority-based requirement for each of the one or more nodes.

49. The method of claim 41 wherein the spatial division multiplexed transmission is initiated by contending for access to the medium to broadcast a message.

50. The method of claim 49 wherein the message identifies the nodes for the spatial division multiplexed transmission.

51. The method of claim 49 wherein data to be transmitted by each of the nodes belongs to an access class comprising contention parameters, and wherein the method further comprises contending for access to the medium using the contention parameters of the access class.

52. The method of claim 51 wherein the contention parameters comprise a minimum contention window size, and wherein the method further comprises contending for access to the medium using a contention window size that is less than the minimum contention window size for the access class.

53. The method of claim 52 wherein the minimum contention window size is equal to a number based on the minimum contention window size for the access class divided by the number of the nodes with data to transmit.

54. The method of claim 49 further comprising receiving a request to send data from each of the nodes in response to the message.

55. The method of claim 41 further comprising broadcasting a message to allocate spatial streams to each of the nodes.

56. The method of claim 55 further comprising receiving a sounding frame from each of the nodes to compute channel state information to enable the data from the spatial streams to be separated.

57. The method of claim 55 further comprising receiving data from each of the nodes on the allocated spatial streams.

58. The method of claim 57 further comprising transmitting an acknowledgement in response to receiving the data from each of the nodes on the allocated spatial streams.

59. The method of claim 41 further comprising signaling other nodes not involved in the spatial division multiplexed transmission to defer transmissions for the duration of the spatial division multiplexed transmission.

60. The method of claim 41 further comprising signaling other nodes not involved in the spatial division multiplexed transmission in compliance with legacy nodes that do not support spatial division multiplexed transmission.

61. A computer-program product for communication, comprising:

a machine-readable medium encoded with instructions executable to;

receive requests for a spatial division multiplexed transmission from a plurality of nodes over a multiple access medium; and

initiate the spatial division multiplexed transmission based on a metric related to one or more of the nodes.

62. An access point, comprising:

a plurality of antennas;

a processing system configured to;

receive requests for a spatial division multiplexed transmission from a plurality of nodes over a multiple access medium; and

initiate the spatial division multiplexed transmission based on a metric related to one or more of the nodes; and

a transceiver configured to interface the processing system to the medium through the antennas.

63. An apparatus for wireless communications, comprising:

a processing system configured to;

generate data belonging to an access class having contention parameters;

precode at least a portion of the data for transmission over a spatial stream; and

enter into post backoff following the spatial stream transmission.

64. The apparatus of claim 63 wherein the post backoff comprises waiting for a predetermined period before entering into a contention process.

65. The apparatus of claim 64 wherein the predetermined period is based on the access class.

66. The apparatus of claim 63 wherein the post backoff is based on a value assigned by an access point.

67. The apparatus of claim 63 wherein the post backoff is based on a number of other apparatuses that transmits during the spatial stream transmission.

69. The apparatus of claim 63 wherein the post backoff comprises waiting for a predetermined period before entering into a contention process.

70. The apparatus of claim 69 wherein the predetermined period is based on the access class.

71. The apparatus of claim 69 wherein the post backoff is based on a value assigned by an access point.

72. The apparatus of claim 69 wherein the post backoff is based on a number of other apparatuses that transmits during the spatial stream transmission.

68. An apparatus for wireless communications, comprising:

means for generating data belonging to an access class having contention parameters;

means for precoding at least a portion of the data for transmission over a spatial stream; and

means for entering into post backoff following the spatial stream transmission.

73. A method for wireless communications, comprising:

generating data belonging to an access class having contention parameters;

precoding at least a portion of the data for transmission over a spatial stream; and

entering into post backoff following the spatial stream transmission.

74. The method of claim 73 wherein the post backoff comprises waiting for a predetermined period before entering into a contention process.

75. The method of claim 74 wherein the predetermined period is based on the access class.

76. The method of claim 74 wherein the predetermined period is based on a value assigned by an access point.

77. The method of claim 74 wherein the predetermined period is based on a number of other apparatuses that transmits during the spatial stream transmission.

78. A computer-program product for communication, comprising:

a machine-readable medium encoded with instructions executable to;

generate data belonging to an access class having contention parameters;

precode at least a portion of the data for transmission over a spatial stream; and

enter into post backoff following the spatial stream transmission.

79. A station, comprising:

a user interface; and

a processing system configured to;

generate data in response to the user interface, the data belonging to an access class having contention parameters, and

precode at least a portion of the data for transmission over a spatial stream and enter into post backoff following the spatial stream transmission.