Conditional scheduling for asynchronous wireless communication

• US 8,310,996 B2
• Filed: 08/03/2007
• Issued: 11/13/2012
• Est. Priority Date: 08/07/2006
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Nanda, Sanjiv, Sampath, Ashwin
• Primary Examiner(s): Pham, Chi
• Assistant Examiner(s): HYUN, SOON D
• Application Number:
  US11/833,927
• Publication Number:
  US 20080031172A1
• Time in Patent Office: 1,929 Days
• Field of Search: None
• US Class Current: 370/329
• CPC Class Codes: H04W 72/27 between access points

Abstract

A wireless media access control supports asynchronous communication and overlapping transmissions. Here, a wireless node may determine whether to request or schedule a transmission based on control messages it receives from neighboring nodes. In some implementations a scheduled transmission may be divided up into several segments so that a transmitting node may receive and transmit control messages between segments. In some implementations a monitoring period is defined after a scheduled transmission period to enable the transmitting node to acquire control information that may otherwise have been transmitted during the scheduled transmission period. In some implementations data and control information are transmitted over different frequency division multiplexed channels to enable concurrent transmission of the data and control information.

Claims

1. A method of wireless communication, comprising:

receiving, at a first wireless node, information that indicates a scheduled transmission of data by a second wireless node; and

determining, at the first wireless node, based on the received information, whether to schedule an additional data transmission to be transmitted by a third wireless device during a time period associated with the scheduled data transmission.

2. The method of claim 1, wherein the received information comprises a confirmation message generated by the second wireless node in response to a received grant.

3. The method of claim 2, wherein the confirmation message comprises at least one of the group consisting of:

transmission start time, transmission end time, transmission time period, transmit power delta, packet format, and a pilot signal.

4. The method of claim 1, wherein the determination of whether to schedule the additional data transmission is based on a received signal strength indication associated with a received confirmation message.

5. The method of claim 1, wherein the time period overlaps the scheduled data transmission.

6. The method of claim 1, further comprising transmitting a message from the first wireless node to the third wireless node, wherein the message comprises a schedule for the additional data transmission based on the determination.

7. A method of wireless communication, comprising:

receiving, at a first wireless node, information that indicates a scheduled transmission of data by a second wireless node, wherein the scheduled transmission of data is associated with a scheduled transmit time period; and

determining, at the first wireless node, based on the received information, whether to schedule an additional data transmission during a time period associated with the scheduled data transmission;

wherein data is transmitted by the second wireless node during a plurality of time segments defined within the scheduled transmit time period; and

wherein a time interval for transmission or reception of control information is temporally located between the time segments.

8. The method of claim 7, wherein the received information comprises a confirmation message that the second wireless node transmitted during the time interval.

9. The method of claim 8, wherein the confirmation message comprises at least one of the group consisting of:

transmission start time for at least one of the time segments, transmission end time for at least one of the time segments, transmission time period for at least one of the time segments, transmit power delta, packet format, and a pilot signal.

10. A method of wireless communication, comprising:

receiving, at a first wireless node, information that indicates a scheduled transmission of data by a second wireless node;

determining, at the first wireless node, based on the received information, whether to schedule an additional data transmission during a time period associated with the scheduled data transmission; and

determining, based on the received information, whether the first wireless node will be able to receive the additional data transmission in a sustainable manner during the scheduled transmission of data by the second wireless node;

wherein scheduling of the additional data transmission is based on the sustainable reception determination.

11. The method of claim 10, wherein the scheduling of the additional data transmission comprises at least one of the group consisting of:

abstaining from sending a grant in response to a request to transmit, selecting a different data transmission time, requesting to transmit at a later time, selecting a different transmit time period, selecting a different transmit power, selecting a different quantity of redundancy bits to transmit, and selecting a different code rate.

12. A method of wireless communication, comprising:

receiving, at a first wireless node, information that indicates a scheduled transmission of data by a second wireless node;

determining, at the first wireless node, based on the received information, whether to schedule an additional data transmission during a time period associated with the scheduled data transmission;

defining a rate prediction state based on the received information; and

determining, based on the rate prediction state, whether the first wireless node will be able to receive the additional data transmission in a sustainable manner during the scheduled transmission of data by the second wireless node;

wherein scheduling of the additional data transmission is based on the sustainable reception determination.

13. The method of claim 12, wherein the rate prediction state comprises at least one of the group consisting of:

transmission start time, transmission end time, transmission time period, transmit power delta, and a received signal strength indication associated with a confirmation message.

14. A method of wireless communication, comprising:

receiving, at a first wireless node, information via a control channel, wherein the information indicates a scheduled transmission of data by a second wireless node;

determining, at the first wireless node, based on the received information, whether to schedule an additional data transmission during a time period associated with the scheduled data transmission; and

receiving, at the first wireless node, data via a data channel;

wherein the control channel and the data channel are frequency division multiplexed within a common frequency band; and

wherein the control channel is associated with a plurality of sub-frequency bands that are interspersed within the common frequency band.

15. An apparatus for wireless communication, comprising:

a receiver configured to receive information that indicates a scheduled transmission of data by a wireless node; and

a reception controller configured to determine, based on the received information, whether to schedule an additional data transmission to be transmitted by a second wireless device to the apparatus during a time period associated with the scheduled data transmission.

16. The apparatus of claim 15, wherein the received information comprises a confirmation message generated by the wireless node in response to a received grant.

17. The apparatus of claim 16, wherein the confirmation message comprises at least one of the group consisting of:

transmission start time, transmission end time, transmission time period, transmit power delta, packet format, and a pilot signal.

18. The apparatus of claim 15, further comprising a transmitter configured to transmit a message to the second wireless node, wherein the message comprises a schedule for the additional data transmission based on the determination by the reception controller.

26. The apparatus of claim 15, wherein the determination of whether to schedule the additional data transmission is based on a received signal strength indication associated with a received confirmation message.

19. An apparatus for wireless communication, comprising:

a receiver configured to receive information that indicates a scheduled transmission of data by a wireless node, wherein the scheduled transmission of data is associated with a scheduled transmit time period; and

a reception controller configured to determine, based on the received information, whether to schedule an additional data transmission during a time period associated with the scheduled data transmission;

wherein data is transmitted by the wireless node during a plurality of time segments defined within the scheduled transmit time period; and

wherein a time interval for transmission or reception of control information is temporally located between the time segments.

20. The apparatus of claim 19, wherein the received information comprises a confirmation message that the wireless node transmitted during the time interval.

21. The apparatus of claim 20, wherein the confirmation message comprises at least one of the group consisting of:

transmission start time for at least one of the time segments, transmission end time for at least one of the time segments, transmission time period for at least one of the time segments, transmit power delta, packet format, and a pilot signal.

22. An apparatus for wireless communication, comprising:

a receiver configured to receive information that indicates a scheduled transmission of data by a wireless node;

a reception controller configured to determine, based on the received information, whether to schedule an additional data transmission during a time period associated with the scheduled data transmission; and

a sustainable reception determiner configured to determine, based on the received information, whether the apparatus will be able to receive the additional data transmission in a sustainable manner during the scheduled transmission of data by the wireless node;

wherein scheduling of the additional data transmission is based on the sustainable reception determination.

23. The apparatus of claim 22, wherein the scheduling of the additional data transmission comprises at least one of the group consisting of:

abstaining from sending a grant in response to a request to transmit, selecting a different data transmission time, requesting to transmit at a later time, selecting a different transmit time period, selecting a different transmit power, selecting a different quantity of redundancy bits to transmit, and selecting a different code rate.

24. An apparatus for wireless communication, comprising:

a receiver configured to receive information that indicates a scheduled transmission of data by a wireless node;

a reception controller configured to determine, based on the received information, whether to schedule an additional data transmission during a time period associated with the scheduled data transmission;

a state controller configured to define a rate prediction state based on the received information; and

a sustainable reception determiner configured to determine, based on the rate prediction state, whether the apparatus will be able to receive the additional data transmission in a sustainable manner during the scheduled transmission of data by the wireless node;

wherein scheduling of the additional data transmission is based on the sustainable reception determination.

25. The apparatus of claim 24, wherein the rate prediction state comprises at least one of the group consisting of:

transmission start time, transmission end time, transmission time period, transmit power delta, and a received signal strength indication associated with a confirmation message.

27. An apparatus for wireless communication, comprising:

a receiver configured to receive information via a control channel, wherein the information indicates a scheduled transmission of data by a wireless node, and to receive data via a data channel; and

a reception controller configured to determine, based on the received information, whether to schedule an additional data transmission during a time period associated with the scheduled data transmission;

wherein the control channel and the data channel are frequency division multiplexed within a common frequency band; and

wherein the control channel is associated with a plurality of sub-frequency bands that are interspersed within the common frequency band.

28. An apparatus for wireless communication, comprising:

means for receiving information that indicates a scheduled transmission of data by a wireless node; and

means for determining, based on the received information, whether to schedule an additional data transmission to be transmitted by a second wireless device to the apparatus during a time period associated with the scheduled data transmission.

29. The apparatus of claim 28, wherein the received information comprises a confirmation message generated by the wireless node in response to a received grant.

30. The apparatus of claim 29, wherein the confirmation message comprises at least one of the group consisting of:

transmission start time, transmission end time, transmission time period, transmit power delta, packet format, and a pilot signal.

31. The apparatus of claim 28, wherein the determination of whether to schedule the additional data transmission is based on a received signal strength indication associated with a received confirmation message.

32. The apparatus of claim 28, further comprising means for transmitting a message to the second wireless node, wherein the message comprises a schedule for the additional data transmission based on the determination by the means for determining.

33. An apparatus for wireless communication, comprising:

means for receiving information that indicates a scheduled transmission of data by a wireless node, wherein the scheduled transmission of data is associated with a scheduled transmit time period; and

means for determining, based on the received information, whether to schedule an additional data transmission during a time period associated with the scheduled data transmission;

wherein data is transmitted by the second wireless node during a plurality of time segments defined within the scheduled transmit time period; and

wherein a time interval for transmission or reception of control information is temporally located between the time segments.

34. The apparatus of claim 33, wherein the received information comprises a confirmation message that the wireless node transmitted during the time interval.

35. The apparatus of claim 34, wherein the confirmation message comprises at least one of the group consisting of:

transmission start time for at least one of the time segments, transmission end time for at least one of the time segments, transmission time period for at least one of the time segments, transmit power delta, packet format, and a pilot signal.

36. An apparatus for wireless communication, comprising:

means for receiving information that indicates a scheduled transmission of data by a wireless node;

means for determining, based on the received information, whether to schedule an additional data transmission during a time period associated with the scheduled data transmission; and

means for determining, based on the received information, whether the apparatus will be able to receive the additional data transmission in a sustainable manner during the scheduled transmission of data by the wireless node;

wherein scheduling of the additional data transmission is based on the sustainable reception determination.

37. The apparatus of claim 36, wherein the scheduling of the additional data transmission comprises at least one of the group consisting of:

abstaining from sending a grant in response to a request to transmit, selecting a different data transmission time, requesting to transmit at a later time, selecting a different transmit time period, selecting a different transmit power, selecting a different quantity of redundancy bits to transmit, and selecting a different code rate.

38. An apparatus for wireless communication, comprising:

means for receiving information that indicates a scheduled transmission of data by a wireless node;

means for determining, based on the received information, whether to schedule an additional data transmission during a time period associated with the scheduled data transmission;

means for defining a rate prediction state based on the received information; and

means for determining, based on the rate prediction state, whether the apparatus will be able to receive the additional data transmission in a sustainable manner during the scheduled transmission of data by the wireless node;

wherein scheduling of the additional data transmission is based on the sustainable reception determination.

39. The apparatus of claim 38, wherein the rate prediction state comprises at least one of the group consisting of:

transmission start time, transmission end time, transmission time period, transmit power delta, and a received signal strength indication associated with a confirmation message.

40. An apparatus for wireless communication, comprising:

means for receiving information via a control channel, wherein the received information indicates a scheduled transmission of data by a wireless node;

means for determining, based on the received information, whether to schedule an additional data transmission during a time period associated with the scheduled data transmission; and

means for receiving data via a data channel;

wherein the control channel and the data channel are frequency division multiplexed within a common frequency band; and

wherein the control channel is associated with a plurality of sub-frequency bands that are interspersed within the common frequency band.

41. A computer-program product for wireless communication, comprising:

non-transitory computer-readable storage medium encoded with codes executable by at least one computer to;

receive, at a first wireless node, information that indicates a scheduled transmission of data by a second wireless node; and

determine, at the first wireless node, based on the received information, whether to schedule an additional data transmission to be transmitted by a third wireless device during a time period associated with the scheduled data transmission.

42. An access point for wireless communication, comprising:

an antenna;

a receiver configured to receive via the antenna information that indicates a scheduled transmission of data by a wireless node; and

a reception controller configured to determine, based on the received information, whether to schedule an additional data transmission to be transmitted by a second wireless device to the access point during a time period associated with the scheduled data transmission.

43. An access terminal for wireless communication, comprising:

a receiver configured to receive information that indicates a scheduled transmission of data by a wireless node; and

a reception controller configured to determine, based on the received information, whether to schedule an additional data transmission to be transmitted by a second wireless device to the access terminal during a time period associated with the scheduled data transmission; and

a user interface configured to output an indication based on data received by the receiver.

44. A method of wireless communication, comprising:

defining information that indicates a scheduled transmission of data by a first wireless node, wherein the information is defined to enable a second wireless node to determine whether to schedule an additional data transmission during a time period associated with the scheduled data transmission and the time period overlaps the scheduled data transmission; and

transmitting the defined information by the first wireless node.

45. The method of claim 44, wherein the defined information comprises a confirmation message generated in response to a received grant.

46. The method of claim 45, wherein the confirmation message comprises at least one of the group consisting of:

transmission start time, transmission end time, transmission time period, transmit power delta, packet format, and a pilot signal.

47. The method of claim 44, wherein the defined information is based on a grant message that was received at the first wireless node in response to a request to transmit message issued by the first wireless node.

48. The method of claim 44, further comprising:

obtaining information relating to a scheduled transmit time period of the second wireless node; and

scheduling transmission of the defined information based on the obtained information.

49. A method of wireless communication, comprising:

defining information that indicates a scheduled transmission of data by a first wireless node, wherein the information is defined to enable a second wireless node to determine whether to schedule an additional data transmission during a time period associated with the scheduled data transmission;

transmitting the defined information by the first wireless node; and

transmitting data during a plurality of time segments defined within a scheduled transmit time period;

wherein a time interval for transmission or reception of control information is temporally located between the time segments.

50. The method of claim 49, wherein the defined information comprises a confirmation message that is transmitted during the time interval.

51. The method of claim 50, wherein the confirmation message comprises at least one of the group consisting of:

transmission start time for at least one of the time segments, transmission end time for at least one of the time segments, transmission time period for at least one of the time segments, transmit power delta, packet format, and a pilot signal.

52. A method of wireless communication, comprising:

defining information that indicates a scheduled transmission of data by a first wireless node, wherein the information is defined to enable a second wireless node to determine whether to schedule an additional data transmission during a time period associated with the scheduled data transmission;

transmitting the defined information by the first wireless node via a control channel; and

transmitting data by the first wireless node via a data channel;

wherein the control channel and the data channel are frequency division multiplexed within a common frequency band; and

wherein the control channel is associated with a plurality of sub-frequency bands that are interspersed within the common frequency band.

53. A method of wireless communication, comprising:

defining information that indicates a scheduled transmission of data by a first wireless node, wherein the defined information is defined to enable a second wireless node to determine whether to schedule an additional data transmission during a time period associated with the scheduled data transmission;

obtaining information relating to a scheduled transmit time period of the second wireless node;

scheduling transmission of the defined information based on the obtained information; and

transmitting the defined information by the first wireless node;

wherein the transmission of the defined information is scheduled to commence after the scheduled transmit time period.

54. An apparatus for wireless communication, comprising:

a transmission controller configured to define information that indicates a scheduled transmission of data by the apparatus, wherein the information is defined to enable a wireless node to determine whether to schedule an additional data transmission during a time period associated with the scheduled data transmission and the time period overlaps the scheduled data transmission; and

a transmitter configured to transmit the defined information by the apparatus.

55. The apparatus of claim 54, wherein the defined information comprises a confirmation message generated in response to a received grant.

56. The apparatus of claim 55, wherein the confirmation message comprises at least one of the group consisting of:

transmission start time, transmission end time, transmission time period, transmit power delta, packet format, and a pilot signal.

57. The apparatus of claim 54, wherein the defined information is based on a grant message that was received at the apparatus in response to a request to transmit message issued by the apparatus.

58. The apparatus of claim 54, wherein:

the apparatus further comprises a receiver configured to obtain information relating to a scheduled transmit time period of the wireless node; and

the transmission controller is further configured to schedule transmission of the defined information based on the obtained information.

59. An apparatus for wireless communication, comprising:

a transmission controller configured to define information that indicates a scheduled transmission of data by the apparatus, wherein the information is defined to enable a wireless node to determine whether to schedule an additional data transmission during a time period associated with the scheduled data transmission; and

a transmitter configured to transmit the defined information and to transmit data during a plurality of time segments defined within a scheduled transmit time period;

wherein a time interval for transmission or reception of control information is temporally located between the time segments.

60. The apparatus of claim 59, wherein the defined information comprises a confirmation message that is transmitted during the time interval.

61. The apparatus of claim 60, wherein the confirmation message comprises at least one of the group consisting of:

transmission start time for at least one of the time segments, transmission end time for at least one of the time segments, transmission time period for at least one of the time segments, transmit power delta, packet format, and a pilot signal.

62. An apparatus for wireless communication, comprising:

a transmission controller configured to define information that indicates a scheduled transmission of data by the apparatus, wherein the information is defined to enable a wireless node to determine whether to schedule an additional data transmission during a time period associated with the scheduled data transmission; and

a transmitter configured to transmit the defined information via a control channel and to transmit data via a data channel;

wherein the control channel and the data channel are frequency division multiplexed within a common frequency band; and

wherein the control channel is associated with a plurality of sub-frequency bands that are interspersed within the common frequency band.

63. An apparatus for wireless communication, comprising:

a receiver configured to obtain information relating to a scheduled transmit time period of the wireless node;

a transmission controller configured to define information that indicates a scheduled transmission of data by the apparatus, wherein the defined information is defined to enable a wireless node to determine whether to schedule an additional data transmission during a time period associated with the scheduled data transmission, and to schedule transmission of the defined information based on the obtained information; and

a transmitter configured to transmit the defined information;

wherein the transmission of the defined information is scheduled to commence after the scheduled transmit time period.

64. An apparatus for wireless communication, comprising:

means for defining information that indicates a scheduled transmission of data by the apparatus, wherein the information is defined to enable a wireless node to determine whether to schedule an additional data transmission during a time period associated with the scheduled data transmission and the time period overlaps the scheduled data transmission; and

means for transmitting the defined information by the apparatus.

65. The apparatus of claim 64, wherein the defined information comprises a confirmation message generated in response to a received grant.

66. The apparatus of claim 65, wherein the confirmation message comprises at least one of the group consisting of:

transmission start time, transmission end time, transmission time period, transmit power delta, packet format, and a pilot signal.

67. The apparatus of claim 64, wherein the defined information is based on a grant message that was received at the apparatus in response to a request to transmit message issued by the apparatus.

68. The apparatus of claim 64, wherein:

the apparatus further comprises means for obtaining information relating to a scheduled transmit time period of the wireless node; and

the means for defining information schedules transmission of the defined information based on the obtained information.

69. An apparatus for wireless communication, comprising:

means for defining information that indicates a scheduled transmission of data by the apparatus, wherein the information is defined to enable a wireless node to determine whether to schedule an additional data transmission during a time period associated with the scheduled data transmission; and

means for transmitting the defined information and transmitting data during a plurality of time segments defined within a scheduled transmit time period;

wherein a time interval for transmission or reception of control information is temporally located between the time segments.

70. The apparatus of claim 69, wherein the defined information comprises a confirmation message that is transmitted during the time interval.

71. The apparatus of claim 70, wherein the confirmation message comprises at least one of the group consisting of:

transmission start time for at least one of the time segments, transmission end time for at least one of the time segments, transmission time period for at least one of the time segments, transmit power delta, packet format, and a pilot signal.

72. An apparatus for wireless communication, comprising:

means for defining information that indicates a scheduled transmission of data by the apparatus, wherein the information is defined to enable a wireless node to determine whether to schedule an additional data transmission during a time period associated with the scheduled data transmission;

means for transmitting the defined information via a control channel; and

means for transmitting data via a data channel;

wherein the control channel and the data channel are frequency division multiplexed within a common frequency band; and

wherein the control channel is associated with a plurality of sub-frequency bands that are interspersed within the common frequency band.

73. An apparatus for wireless communication, comprising:

means for obtaining information relating to a scheduled transmit time period of the wireless node;

means for defining information that indicates a scheduled transmission of data by the apparatus, wherein the defined information is defined to enable a wireless node to determine whether to schedule an additional data transmission during a time period associated with the scheduled data transmission;

scheduling transmission of the defined information based on the obtained information; and

means for transmitting the defined information by the apparatus;

wherein the transmission of the defined information is scheduled to commence after the scheduled transmit time period.

74. A computer-program product for wireless communication, comprising:

non-transitory computer-readable storage medium encoded with codes executable by at least one computer to;

define information that indicates a scheduled transmission of data by a first wireless node, wherein the information is defined to enable a second wireless node to determine whether to schedule an additional data transmission during a time period associated with the scheduled data transmission and the time period overlaps the scheduled data transmission; and

transmit the defined information by the first wireless node.

75. An access point for wireless communication, comprising:

an antenna;

a transmission controller configured to define information that indicates a scheduled transmission of data by the apparatus, wherein the information is defined to enable a wireless node to determine whether to schedule an additional data transmission during a time period associated with the scheduled data transmission and the time period overlaps the scheduled data transmission; and

a transmitter configured to transmit the defined information via the antenna.

76. An access terminal for wireless communication, comprising:

a transmission controller configured to define information that indicates a scheduled transmission of data by the apparatus, wherein the information is defined to enable a wireless node to determine whether to schedule an additional data transmission during a time period associated with the scheduled data transmission and the time period overlaps the scheduled data transmission; and

a transmitter configured to transmit the defined information by the apparatus; and

a user interface configured to provide data to be transmitted by the transmitter.

77. A method of wireless communication, comprising:

receiving, at a first wireless node, information that indicates a scheduled transmission of data by a second wireless node; and

determining, at the first wireless node, based on the received information, whether to schedule an additional data transmission during a time period associated with the scheduled data transmission;

wherein the received information comprises a confirmation message generated by the second wireless node in response to a grant previously transmitted by a third wireless node in response to a request to transmit issued by the second wireless node.

78. A method of wireless communication, comprising:

defining information that indicates a scheduled transmission of data by a first wireless node, wherein the information is defined to enable a second wireless node to determine whether to schedule an additional data transmission during a time period associated with the scheduled data transmission, wherein the additional data transmission is by a third wireless node; and

transmitting the defined information by the first wireless node.

79. A method of wireless communication, comprising:

defining information that indicates a scheduled transmission of data by a first wireless node, wherein the information is defined to enable a second wireless node to determine whether to schedule an additional data transmission during a time period associated with the scheduled data transmission; and

transmitting the defined information by the first wireless node;

wherein the defined information comprises a confirmation message generated in response to a grant previously transmitted by a third wireless node in response to a request to transmit issued by the first wireless node.