Efficient signaling over access channel

• US 20060018336A1
• Filed: 12/22/2004
• Published: 01/26/2006
• Est. Priority Date: 07/21/2004
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Gorokhov, Alexei, Sutivong, Arak, Teague, Edward Harrison
• Granted Patent: US 9,137,822 B2
• Time in Patent Office: Days
• US Class Current: 370/437
• CPC Class Codes: H04L 1/0023 characterised by the signalling
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 1/1692 Physical properties of the supervisory signal, e.g. acknowledgement by energy bursts
• CPC Class Codes: H04W 52/04 TPC
• CPC Class Codes: H04W 72/542 using measured or perceived quality
• CPC Class Codes: H04W 74/004 in the uplink, i.e. towards network
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access

Abstract

An apparatus and method for transmitting an indicator of channel quality while minimizing the use of a broadcast channel is described. A metric of forward link geometry of observed transmission signals is determined. An indicator of channel quality value is determined as a function of the observed transmission signals. An access sequence is selected, randomly, from one group of a plurality of groups of access sequences, wherein each of the plurality of groups of access sequences correspond to different ranges of channel quality values.

Claims

1. In a wireless communication system, a method of determining an indicator of channel quality, the method comprising:

determining a metric of an observed transmission;

determining an estimate of channel quality based on at least the metric of the observed transmission; and

selecting an access sequence, randomly, from one group of a plurality of groups of access sequences, wherein the plurality of groups of access sequences correspond to different ranges of channel quality values, and wherein the selected access sequence is from the group of the plurality of groups corresponding to the determined estimate of channel quality.

2. The method set forth in claim 1, wherein determining the metric further comprises determining the power of an observed pilot signal.

3. The method set forth in claim 1, wherein determining the estimate of channel quality further comprises determining the ratio of received pilot power to noise.

4. The method set forth in claim 1, wherein determining the estimate of channel quality further comprises determining the ratio of received pilot power to the sum of received pilot and power and noise.

5. The method set forth in claim 1, wherein the plurality of access sequences in the plurality of groups of access sequences are distributed non-uniformly.

6. The method set forth in claim 1, further comprising transmitting the selected access sequence.

7. The method set forth in claim 6, wherein transmitting further comprises transmitting in accordance with a Frequency Division Multiplex (FDM) scheme.

8. The method set forth in claim 6, wherein transmitting further comprises transmitting in accordance with a Code Division Multiplex (CDM) scheme.

9. The method set forth in claim 6, wherein the act of transmitting further comprises transmitting in accordance with an Orthogonal Frequency Division Multiple Access (OFDMA) scheme.

10. The method set forth in claim 1, wherein selecting further comprises selecting information indicative of access terminal requirements.

11. The method set forth in claim 10, wherein selecting information further comprises selecting information buffer level needs, quality of service requirements, a forward-link channel quality indicator.

19. The apparatus set forth in claim 11, wherein the selector is further configured to select information indicative of access terminal requirements.

20. The apparatus set forth in claim 19, wherein the information indicative of access terminal requirements comprises buffer level, quality of service requirements, a forward-link channel quality indicator.

12. In a wireless communication system, an apparatus to determine an indicator of channel quality, the apparatus comprising:

a receiver configured to receive observed transmissions;

a processor configured to determine a metric of the observed transmission, and to determine an estimate of channel quality as a function of at least the metric of the observed transmission;

a memory element configured to store a plurality of groups of access sequences, wherein the plurality of groups of access sequences correspond to different ranges of channel quality values; and

a selector configured to select an access sequence, randomly, from the group of the plurality of groups corresponding to the determined channel quality value.

13. The apparatus set forth in claim 12, the processor further comprises determining the ratio of received pilot power to noise.

14. The apparatus set forth in claim 12, the plurality of access sequences in the plurality of groups of access sequences are distributed non-uniformly.

15. The apparatus set forth in claim 12, further comprising a transmitter configured to transmit the selected access sequence.

16. The apparatus set forth in claim 15, wherein the transmitter is further configured to transmit in accordance with a Frequency Division Multiplex (FDM) scheme.

17. The apparatus set forth in claim 15, wherein the transmitter is further configured to transmit in accordance with a Code Division Multiplex (CDM) scheme.

18. The apparatus set forth in claim 14, wherein the transmitter is further configured to transmit in accordance with an Orthogonal Frequency Division Multiple Access (OFDMA) scheme.

21. In a wireless communication system, an apparatus for determining an indicator of channel quality, the means comprising:

means for determining a power level of an observed transmission;

means for determining a CQI value as a function of the power level of the observed transmission; and

means for selecting an access sequence, randomly, from one group of a plurality of groups of access sequences, wherein the plurality of groups of access sequences correspond to different ranges of CQI values, and wherein the selected access sequence is from the group of the plurality of groups corresponding to the determined CQI value.

22. The apparatus set forth in claim 21, wherein means for determining a power level further comprises means for determining the power level of an observed pilot signal.

23. The apparatus set forth in claim 21, wherein the plurality of access sequences in the plurality of groups of access sequences are distributed non-uniformly.

24. The apparatus set forth in claim 21, further comprising means for transmitting the selected access sequence.

25. The apparatus set forth in claim 24, wherein means for transmitting further comprises means for transmitting in accordance with a Frequency Division Multiplex (FDM) scheme.

26. The apparatus set forth in claim 24, wherein means for transmitting further comprises means for transmitting in accordance with a Code Division Multiplex (CDM) scheme.

27. The apparatus set forth in claim 24, wherein means for transmitting further comprises transmitting in accordance with an Orthogonal Frequency Division Multiplex (OFDM) scheme.

28. The apparatus set forth in claim 24, wherein the means for transmitting further comprises means for transmitting in accordance with an Orthogonal Frequency Division Multiple Access (OFDMA) scheme.

29. The apparatus set forth in claim 21, wherein selecting further comprises means for selecting information indicative of access terminal requirements.

30. The apparatus set forth in claim 29, wherein means for selecting information further comprises selecting information regarding buffer level needs, quality of service requirements, and/or a forward-link channel quality indicator.

31. In a wireless communication system, a method of transmitting information regarding access terminal needs, the method comprising:

determining a received power level of an observed pilot signal;

determining a CQI value as a function of the received power level; and

selecting an access sequence, randomly, from one group of a plurality of groups of access sequences, wherein the plurality of groups of access sequences correspond to a plurality of predetermined factors.

32. The method set forth in claim 31, wherein the predetermined factors include on or more of ranges of CQI values, ranges of buffer levels, packet size, traffic type, frequency bandwidth request and ranges of quality of service indicators.

37. The apparatus set forth in claim 31, wherein the predetermined factors include on or more of ranges of CQI values, ranges of buffer levels, packet size, traffic type, frequency bandwidth request and ranges of quality of service indicators.

33. In a wireless communication system, a method of communicating a channel quality indicator (CQI), the method comprising:

determining a power level of an observed pilot signal;

determining a CQI value as a function of the power level of the observed pilot signal;

selecting an access sequence, randomly, from one group of a plurality of groups of access sequences, wherein the plurality of groups of access sequences correspond different the CQI values;

appending the CQI value to the selected access sequence; and

transmitting the access sequence and CQI value.

34. A method of partitioning a plurality of access sequences, the method comprising:

determining a probability distribution of a plurality of access terminals about an access point, wherein the probability distribution is a function of a plurality of access terminals being partitioned into a plurality of sub-groups, wherein each sub-group is categorized as a function of CQI values within a predetermined range; and

assigning groups of access sequences in proportion to the probability distribution.

35. The method set forth in claim 34, further comprising reassigning access sequences as a function of a change in distribution of access terminals about the access point.

40. The apparatus set forth in claim 34, further comprising means for reassigning access sequences as a function of a change in distribution of access terminals about the access point.

36. In a wireless communication system, an apparatus for transmitting information regarding access terminal needs, the apparatus comprising:

means for determining a received power level of an observed pilot signal;

means for determining a CQI value as a function of the received power level; and

means for selecting an access sequence, randomly, from one group of a plurality of groups of access sequences, wherein the plurality of groups of access sequences correspond to a plurality of predetermined factors.

38. In a wireless communication system, an apparatus for communicating a channel quality indicator (CQI), the apparatus comprising:

means for determining a power level of an observed pilot signal;

means for determining a CQI value as a function of the power level of the observed pilot signal;

means for selecting an access sequence, randomly, from one group of a plurality of groups of access sequences, wherein the plurality of groups of access sequences correspond different the CQI values;

means for appending the CQI value to the selected access sequence; and

means for transmitting the access sequence and CQI value.

39. An apparatus for partitioning a plurality of access sequences, the apparatus comprising:

means for determining a probability distribution of a plurality of access terminals about an access point, wherein the probability distribution is a function of a plurality of access terminals being partitioned into a plurality of sub-groups, wherein each sub-group is categorized as a function of CQI values within a predetermined range; and

means for assigning groups of access sequences in proportion to the probability distribution.

41. In a wireless communication system, a method of transmitting an acknowledgement of a detected access sequence, the method comprising:

receiving an access sequence;

determining at least one attribute of a given access terminal as a function of the access sequence; and

transmitting information commensurate with the at least one attribute.

42. The method set forth in claim 41, wherein the attribute is at least one of a channel quality indicator, a buffer level indicator, a priority indicator and a quality of service indicator.

43. The method set forth in claim 41, wherein the transmitting information further comprises transmitting an indictor of acknowledgment.

44. The method set forth in claim 43, further comprising transmitting an indicator of acknowledgment over a shared signaling channel (SSCH).

45. The method set forth in claim 44, wherein the indicator of acknowledgment is included in a particular section of a shared signaling channel (SSCH), wherein the section of the SSCH is partitioned on a basis of the transmission power needed for the indicator of acknowledgment to be successfully received.

46. In a wireless communication system, a memory medium comprising N dimensions, wherein at least one of the dimensions comprises data correlating access sequences with indicators of channel quality.

47. The memory medium of claim 46, further comprising a dimension comprising data correlating access sequences with buffer level.

48. The memory medium of claim 46, further comprising a dimension comprising data correlating access sequences with packet size.

49. The memory medium of claim 46, further comprising a dimension comprising data correlating access sequences with traffic type.

50. The memory medium of claim 46, further comprising a dimension comprising data correlating access sequences with quality of service indicators.

51. The memory medium of claim 46, further comprising a dimension comprising data correlating access sequences with requests regarding frequency bandwidth.

52. In a wireless communication system, an apparatus for transmitting an acknowledgement of a detected access sequence, the apparatus comprising:

means for receiving an access sequence;

means for determining at least one attribute of a given access terminal as a function of the access sequence; and

means for transmitting information commensurate with the at least one attribute.

53. The apparatus set forth in claim 52, wherein the attribute is at least one of a channel quality indicator, a buffer level indicator, a priority indicator and a quality of service indicator.

54. The apparatus set forth in claim 52, wherein the means for transmitting information further comprises transmitting an indictor of acknowledgment.

55. The apparatus set forth in claim 54, further comprising means for transmitting an indicator of acknowledgment over a shared signaling channel (SSCH).

56. The apparatus set forth in claim 54, wherein the indicator of acknowledgment is included in a particular section of a shared signaling channel (SSCH), wherein the section of the SSCH is partitioned on a basis of the transmission power needed for the indicator of acknowledgment to be successfully received.