Method and apparatus for improving performance of erasure sequence detection

• US 8,804,627 B2
• Filed: 12/19/2007
• Issued: 08/12/2014
• Est. Priority Date: 12/19/2007
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Akkarakaran, Sony John, Tsai, Ming-Chang, Ji, Tingfang
• Primary Examiner(s): BLANTON, JOHN D
• Application Number:
  US11/960,349
• Publication Number:
  US 20090161606A1
• Time in Patent Office: 2,428 Days
• US Class Current: 370/329
• CPC Class Codes: H04L 1/1812 Hybrid protocols; Hybrid automatic repeat request [HARQ]
• CPC Class Codes: H04L 1/1887 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 9/3247 involving digital signatures
• CPC Class Codes: H04W 28/06 Optimizing the usage of the radio link, e.g. header compression, information sizing , discarding information system modifying transmission characteristic according to link quality by modifying frame length H04L1/0007; dynamic adaptation of the packet size for flow control or congestion control H04L47/365
• CPC Class Codes: H04W 72/04 Wireless resource allocation

Abstract

Attributes of access terminals are employed in determining durations for erasure sequences. Transmissions from access terminals are analyzed to determine different attributes are based at least on these attributes traffic models are estimated. Those terminals whose traffic models tend towards more frequent occurrences of longer erasures are assigned longer erasure durations to improve performance in erasure sequence detection.

Claims

1. A method of transmission that facilitates erasure detection, comprising:

receiving, at an access point, one or more communications from an access terminal;

estimating, from the one or more communications, one or more attributes associated with the access terminal, wherein the one or more attributes relate to one or both of a size of bandwidth to be assigned to the access terminal and a traffic model of the access terminal;

assigning an erasure sequence duration for one or more erasure sequences based at least on the one or more attributes, wherein each of the one or more erasure sequences comprises a packet added to a frame by the access terminal for filling in a gap in the frame between data transmissions when the gap is detected by the access terminal, and wherein the packet comprises an identifier known to both the access terminal and the access point; and

communicating the erasure sequence duration to the access terminal in a message assigning resources to the access terminal, wherein no data transmissions occur with the access terminal during the erasure sequence duration.

2. The method of claim 1, wherein the message assigning resources comprises a sticky assignment.

3. The method of claim 1, wherein the one or more attributes are associated with the bandwidth size to be assigned to the access terminal, and wherein a shorter erasure sequence duration is assigned when the access terminal is associated with a higher bandwidth and a longer erasure sequence duration is assigned when the access terminal is associated with a lower bandwidth.

4. The method of claim 1, wherein the one or more attributes are further associated with a received signal strength of the access terminal, and wherein a shorter erasure sequence duration is assigned when the access terminal has a higher signal strength and a longer erasure sequence duration is assigned when the access terminal has a lower signal strength.

5. The method of claim 1, wherein the one or more attributes are associated with the traffic model of the access terminal, and wherein the access terminal is assigned a longer erasure sequence duration when the access terminal is associated with a traffic model of the access terminal having more frequent occurrences of longer erasures and the access terminal is assigned a shorter erasure sequence duration when the access terminal is associated with a traffic model of the access terminal having infrequent occurrences of longer erasures.

6. The method of claim 1, further comprising monitoring burst statistics of the access terminal to determine the appropriate erasure sequence duration for assignment.

7. The method of claim 6, wherein the monitoring burst statistics further comprises:

computing a histogram that provides probabilities of occurrences of bursts of consecutive erasures of different lengths; and

computing a mean burst length based at least in part on the histogram.

8. The method of claim 6, further comprising:

assigning the erasure sequence duration such that an average value a latency of the access terminal due to the assigned erasure sequence duration remains constant.

9. The method of claim 1, further comprising monitoring one or more QoS (quality of service) flows of the access terminal to determine the appropriate erasure sequence duration for assignment.

10. The method of claim 9, wherein the monitoring one or more QoS flows further comprises monitoring a plurality of QoS flows associated with the access terminal implementing MIMO (multiple input multiple output) or SIMO (single input multiple output) communications such that different QoS flows are assigned different erasure sequence durations.

11. The method of claim 1, further comprising monitoring the access terminal for variations in the one or more attributes and reassigning the erasure sequence duration when the one or more attributes vary beyond a predetermined range.

12. An apparatus for erasure sequence detection, comprising:

a communications component, comprising hardware, that facilitates information exchange between an access point and one or more access terminals;

an estimation component, comprising hardware, that estimates one or more attributes associated with the one or more access terminals via the communications received from the one or more access terminals, wherein the one or more attributes for each of the one or more access terminals relate to one or both of a size of bandwidth to be assigned to the access terminal and a traffic model of the access terminal; and

an assigning component, comprising hardware, that assigns an erasure sequence duration for one or more erasure sequences to each of the one or more access terminals based on their respective one or more attributes, wherein each of the one or more erasure sequences comprises a packet added to a frame by the access terminal for filling in a gap in the frame between data transmissions when the gap is detected by the access terminal, and wherein the packet comprises an identifier known to both the access terminal and the access point,

wherein the communications component transmits a resource assignment message to at least one of the one or more access terminals, wherein the resource assignment message comprises the assigned erasure sequence durations for each of the one or more access terminals, and wherein no data transmissions occur with the one or more access terminals during the erasure sequence duration.

13. The apparatus of claim 12, wherein information received from the one or more access terminals relates to one or more of respective capabilities, estimates of respective downlink channel conditions, and subscriber data associated with each of the access terminals.

14. The apparatus of claim 12, wherein the resource assignment message comprises a sticky assignment.

15. The apparatus of claim 14, wherein the resource assignment message is a group assignment message transmitted to a group comprising at least one of the one or more access terminals and the resource assignment message conveys information regarding resources assigned to the group.

16. The apparatus of claim 12, wherein the assigning component further employs current context data obtained from received transmissions or historical data associated with users employing the one or more access terminals to determine durations of erasure sequences.

17. The apparatus of claim 12, wherein at least one of the one or more access terminals comprises a plurality of antennas that implement at least one of MIMO (multiple input multiple output) and SIMO (single input multiple output) schemes for communications.

18. The apparatus of claim 17, wherein the at least one access terminal implementing one of MIMO and SIMO schemes transmits a plurality of data streams from the plurality of antennas, and wherein the plurality of data streams are associated with different QoS (quality of service) parameters.

19. The apparatus of claim 18, wherein the assigning component assigns different values of erasure sequence durations to each of the plurality of data streams that have been assigned resources in sticky assignments.

20. The apparatus of claim 12, wherein the estimation component tracks variations in the one or more attributes of the one or more access terminals and the assigning component varies erasure sequence durations to the one or more access terminals based on respective variations in the one or more attributes.

21. A non-transitory processor readable medium comprising:

instructions for causing a processor to receive, at an access point, one or more communications from an access terminal;

instructions for causing the processor to estimate, from the one or more communications, one or more attributes associated with the access terminal, wherein the one or more attributes relate to one or both of a size of bandwidth to be assigned to the access terminal and a traffic model of the access terminal;

instructions for causing the processor to assign an erasure sequence duration for one or more erasure sequences based on the estimated attributes, wherein each of the one or more erasure sequences corresponds to a packet added to a frame by the access terminal for filling in a gap in the frame between data transmissions when the gap is detected by the access terminal, and wherein the packet comprises an identifier known to both the access terminal and the access point; and

instructions for causing the processor to communicate the assigned erasure sequence duration to the access terminal in a message assigning resources to the access terminal, and wherein no data transmissions occur with the access terminal during the erasure sequence duration.

22. The processor readable medium of claim 21, further comprising instructions for causing the processor to assign the resources to the access terminal for a predetermined period.

23. The processor readable medium of claim 21, wherein the one or more estimated attributes are associated with the bandwidth size to be assigned to the access terminal, and wherein the erasure sequence duration is assigned so that when the access terminal has a higher bandwidth, a shorter erasure sequence duration is assigned to the access terminal, and when the access terminal is associated with a lower bandwidth, a longer erasure sequence duration is assigned to the access terminal.

24. The processor readable medium of claim 21, wherein the one or more attributes are further associated with an received signal strength of the access terminal, and wherein the access terminal is assigned a shorter erasure sequence duration when the access terminal has a higher signal strength and the access terminal is assigned a longer erasure sequence duration when the access terminal has a lower signal strength.

25. The processor readable medium of claim 21, wherein the one or more attributes are associated with the traffic model of the access terminal, and wherein the access terminal is assigned a longer erasure sequence duration when the traffic model of the access terminal is associated with more frequent occurrences of longer erasures, and the access terminal is assigned a shorter erasure sequence duration when the traffic model of the access terminal is associated with infrequent occurrences of longer erasures.

26. The processor readable medium of claim 21, further comprising instructions for causing the processor to monitor burst statistics of a user to determine the appropriate erasure sequence duration for assignment.

27. The processor readable medium of claim 26, wherein the monitoring burst statistics comprise:

computing a histogram that provides the probabilities of occurrences of bursts of consecutive erasures of different lengths; and

computing a mean burst length based at least in part on the histogram.

28. The processor readable medium of claim 26, further comprising instructions for causing a processor to assign the erasure sequence duration such that there is no change in an average value of a latency of the access terminal due to the assigned erasure sequence duration.

29. The processor readable medium of claim 21, further comprising instructions for causing a processor to monitor one or more QoS (quality of service) flows of the access terminal to determine appropriate erasure sequence duration for assignment.

30. The processor readable medium of claim 29, wherein the monitoring one or more QoS flows comprises monitoring a plurality of QoS flows associated with the access terminal implementing MIMO (multiple input multiple output) or SIMO (single input multiple output) communications such that different QoS flows are assigned different erasure sequence durations.

31. The processor readable medium of claim 21, further comprising instructions for causing a processor to monitor the access terminal for variations in the one or more attributes and reassigning the erasure sequence duration when the one or more attributes vary beyond a predetermined range.

32. An apparatus for erasure sequence detection, comprising:

means for communicating, at an access point, with one or more access terminals; and

means for estimating one or more attributes associated with the one or more access terminals via the communications received from the one or more access terminals, wherein the one or more attributes for each of the one or more access terminals relate to one or both of a size of bandwidth to be assigned to the terminal and a traffic model of the access terminal; and

means for assigning erasure sequence durations for one or more erasure sequences to each of the one or more access terminals based on their respective attributes, wherein each of the one or more erasure sequences comprise a packet added to a frame by the access terminal for filling in a gap in the frame between data transmissions when the gap is detected by the access terminal, wherein the packet comprises an identifier known to both the access terminal and the access point, and wherein a resource assignment message is transmitted from the means for communicating to at least one of the one or more access terminals, wherein the resource assignment message comprises the assigned erasure sequence durations for each of the one or more access terminals, and wherein no data transmissions occur with the one or more access terminals during the erasure sequence duration.

33. The apparatus of claim 32, wherein information received from the one or more access terminals relates to one or more of respective capabilities, estimates of respective downlink channel conditions, and subscriber data associated with each of the access terminals.

34. The apparatus of claim 32, wherein the resource assignment message comprises a sticky assignment.

35. The apparatus of claim 32, wherein the resource assignment message is a group assignment message transmitted to a group comprising at least one of the one or more access terminals, the resource assignment message conveying information regarding resources assigned to the group.

36. The apparatus of claim 32, wherein the means for estimating further comprise means for employing current context data from received transmissions or historical data associated with users employing the one or more access terminals to determine the erasure sequences durations.

37. The apparatus of claim 32, wherein at least one of the one or more access terminals implements at least one of MIMO (multiple input multiple output) and SIMO (single input multiple output) for communications.

38. The apparatus of claim 37, wherein the at least one access terminal implementing one of MIMO and SIMO transmits a plurality of data streams, the data streams being associated with different QoS (quality of service) parameters.

39. The apparatus of claim 38, wherein the means for assigning further comprise means for assigning different values of erasure sequence durations to each of the plurality of data streams that have been assigned resources in sticky assignments.

40. The apparatus of claim 32, wherein the means for estimating further comprise means for tracking variations in the one or more attributes of the one or more access terminals and varies erasure sequence durations to the one or more access terminals based on respective variations in the one or more attributes.

41. A method of communication that facilitates erasure detection, comprising:

transmitting, to an access point, one or more attributes, wherein the one or more attributes relate to one or both of a size of bandwidth to be assigned to an access terminal and a traffic model of the access terminal;

receiving erasure sequences durations for one or more erasure sequences, the erasure sequence durations being determined based on the transmitted one or more attributes, wherein each of the one or more erasure sequences comprises a packet comprising an identifier known to both the access terminal and the access point;

detecting a gap in a frame between data transmissions;

adding the packet to the frame for filling in the gap between the data transmissions, wherein the erasure sequence durations are received in a message conveying information regarding resource assignments to the access terminal, and wherein no data transmissions occur with the access terminal during the erasure sequence durations; and

transmitting the data packets alternated with erasure sequences of the received durations.

42. The method of claim 41, wherein the assignment is a sticky assignment.

43. The method of claim 41, further comprising varying the erasure sequence durations while transmitting the data packets based on variations in the one or more attributes.

44. The method of claim 41, further comprising implementing one of MIMO (multiple input multiple output) and SIMO (single input multiple output) system at the access terminal such that data streams with different attributes transmit data packets with erasure sequences of different durations based on respective attributes of the data streams.

45. An apparatus for erasure sequence detection, comprising:

one or more communication components, comprising hardware, associated with an access terminal to transmit and receive information, wherein the one or more communication components are configured to transmit, to an access point, one or more attributes associated with the access terminal, and wherein the one or more attributes relate to one or both of a size of bandwidth to be assigned to the access terminal and a traffic model of the access terminal; and

a processing component configured to;

receive erasure sequence durations for one or more erasure sequences from an access point, the erasure sequence durations being determined based on the one or more attributes, wherein each of the one or more erasure sequences comprises a packet comprising an identifier known to both the access terminal and the access point;

detect a gap in a frame between data transmissions; and

add the packet to the frame for filling in the gap between the data transmissions, wherein the erasure sequences durations are received in a resource assignment message that conveys assignment of resources to the access terminal, and wherein no data transmissions occur with the access terminal during the erasure sequence durations.

46. The apparatus of claim 45, wherein the assignment is a sticky assignment.

47. The apparatus of claim 45, wherein a plurality of the communication components transmit a plurality of data streams and the processing component processes data packets such that the data packets of different data streams are each alternated with respective received erasure sequences of different durations, based on attributes associated with respective data streams.

48. A non-transitory processor readable medium comprising:

instructions for causing a processor to transmit, to an access point, one or more attributes associated with an access terminal, wherein the one or more attributes relate to one or both of a size of bandwidth to be assigned to the access terminal and a traffic model of the access terminal;

instructions for causing the processor to receive erasure sequence durations for one or more erasure sequences, the erasure sequence durations being determined based at least on the transmitted one or more attributes, wherein each of the one or more erasure sequences comprises a packet comprising an identifier known to both the access terminal and the access point;

instructions for detecting a gap in a frame between data transmissions;

instructions for adding the packet to the frame for filling in the gap between data transmissions, wherein the erasure sequence durations are received in a message conveying information regarding resource assignments to the access terminal, and wherein no data transmissions occur with the access terminal during the erasure sequence durations; and

instructions for causing the processor to transmit data packets alternated with erasure sequences of the received durations.

49. The processor readable medium of claim 48, wherein the resource assignment message comprises a sticky assignment.

50. The processor readable medium of claim 49, further comprising instructions for causing the processor to vary the erasure sequence durations based on variations in the one or more attributes.

51. An apparatus for improving erasure sequence detection, comprising:

means for transmitting, to an access point, one or more attributes associated with an access terminal, wherein the one or more attributes relate to one or both of a size of bandwidth to be assigned to the access terminal and a traffic model of the access terminal;

means for receiving erasure sequence durations for one or more erasure sequences, wherein the erasure sequences durations are determined based at least on the one or more transmitted attributes, wherein each of the one or more erasure sequences comprises a packet comprising an identifier known to both the access terminal and the access point;

means for detecting a gap in a frame between data transmissions;

means for adding the packet to the frame for filling in the gap between the data transmissions, and wherein the erasure sequences durations are received in a resource assignment message that conveys assignment of resources to the access terminal; and

means for employing the received durations in generating erasure sequences for transmission, wherein no data transmissions occur with the access terminal during the erasure sequence durations.

52. The apparatus of claim 51, wherein the resource assignment message comprises a sticky assignment.

53. The apparatus of claim 51, wherein the means for transmitting further comprise means for transmitting a plurality of data streams, and wherein the means for employing further comprises means for processing data packets such that data packets of different data streams are alternated with erasure sequences of different durations based at least on the one or more attributes associated with respective data streams.

54. The apparatus of claim 51, wherein the means for transmitting further comprise means for transmitting data packets alternated with erasure sequences of the determined durations.