Generation, Deployment and Use of Tailored Channel Quality Indicator Tables

• US 20070259671A1
• Filed: 11/01/2006
• Published: 11/08/2007
• Est. Priority Date: 05/03/2006
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Cheng, Jung-Fu, Grant, Stephen J., Hui, Dennis, Molnar, Karl James
• Granted Patent: US 7,979,075 B2
• Time in Patent Office: Days
• US Class Current: 455/452.200
• CPC Class Codes: H04L 1/0016 involving special memory structures, e.g. look-up tables
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 1/20 using signal quality detector
• CPC Class Codes: H04W 48/08 Access restriction or access information delivery, e.g. discovery data delivery signalling during connection H04W76/00
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: H04W 72/542 using measured or perceived quality

Abstract

Channel Quality Indicator (CQI) tables are tailored to one or more cells of interest. Tailoring CQI tables to individual cells permits devices such as radio base stations to more reliably and accurately allocate radio resources to those cells since channel conditions vary from cell to cell. According to one embodiment, a table of CQI values is composed by analyzing information indicating channel quality in a cell of interest and generating at least one table of CQI values tailored to the cell of interest based on the information analyzed. The tailored CQI table may be deployed to another device for use in reporting channel quality information. The device may report channel quality by accessing the tailored CQI and identifying the range of CQI values that includes a channel quality estimate derived by the device. The device generates a channel quality information message based on the identified range of CQI values.

Claims

1. A method of indicating channel quality by a wireless communication device, comprising:

accessing a table of channel quality indicator (CQI) values, the table comprising ranges of CQI values determined based on information indicating channel quality in a cell of interest;

identifying the range of CQI values that includes a channel quality estimate derived by the wireless communication device; and

generating a channel quality information message based on the identified range of CQI values.

2. The method of claim 1, wherein the information indicating channel quality in a cell of interest corresponds to previously reported CQI values.

3. The method of claim 1, wherein the information indicating channel quality in a cell of interest corresponds to at least one of cell size, radio frequency reuse patterns, cell terrain features, supported transmit and receive antenna configurations, and signal transmission load conditions.

4. The method of claim 1, wherein the ranges of CQI values have approximately equal probabilities of occurrence.

5. The method of claim 1, wherein the ranges of CQI values have approximately equal costs.

6. The method of claim 1, further comprising receiving the table from a dedicated control channel.

7. The method of claim 1, further comprising receiving the table from a broadcast channel.

8. The method of claim 7, wherein receiving the table from a broadcast channel comprises:

receiving notification, from a dedicated control channel, of a forthcoming CQI table transaction; and

in response to the notification, receiving the table from the broadcast channel.

9. The method of claim 1, wherein the cell of interest comprises a cell in which the wireless communication device is being serviced.

10. The method of claim 9, further comprising accessing a different table of CQI values to generate a subsequent channel quality information message responsive to the wireless communication device being serviced in a different cell, the different table corresponding to the different cell.

11. A wireless communication device, comprising:

a table of channel quality indicator (CQI) values, the table comprising ranges of CQI values determined based on information indicating channel quality in a cell of interest; and

signal processing circuitry configured to derive a channel quality estimate, identify the range of CQI values that includes the channel quality estimate, and generate a channel quality information message based on the identified range of CQI values.

12. The wireless communication device of claim 11, wherein the information indicating channel quality in a cell of interest corresponds to previously reported CQI values.

13. The wireless communication device of claim 11, wherein the information indicating channel quality in a cell of interest corresponds to at least one of cell size, radio frequency reuse patterns, cell terrain features, supported transmit and receive antenna configurations, and signal transmission load conditions.

14. The wireless communication device of claim 11, wherein the ranges of CQI values have approximately equal probabilities of occurrence.

15. The wireless communication device of claim 11, wherein the ranges of CQI values have approximately equal costs.

16. The wireless communication device of claim 11, wherein the signal processing circuitry is further configured to receive the table from a dedicated control channel.

17. The wireless communication device of claim 11, wherein the signal processing circuitry is further configured to receive the table from a broadcast channel.

18. The wireless communication device of claim 17, wherein the signal processing circuitry is configured to receive the table from a broadcast channel by receiving notification of a forthcoming CQI table transaction and in response to receiving the notification, receiving the table from the broadcast channel.

19. The wireless communication device of claim 18, wherein the signal processing circuitry receives the notification from a dedicated control channel.

20. The wireless communication device of claim 18, wherein the signal processing circuitry receives the notification from a broadcast control channel.

21. The wireless communication device of claim 11, wherein the cell of interest comprises a cell in which the wireless communication device is being serviced.

22. The wireless communication device of claim 21, wherein the signal processing circuitry is further configured to generate a subsequent channel quality information message by accessing a different table of CQI values responsive to the wireless communication device being serviced in a different cell, the different table corresponding to the different cell.

23. A method of composing a table of channel quality indicator (CQI) values, comprising:

analyzing information indicating channel quality in a cell of interest; and

generating at least one table of CQI values tailored to the cell of interest based on the information analyzed.

24. The method of claim 23, wherein the information indicating channel quality in a cell of interest corresponds to CQI data received from one or more wireless communication devices.

25. The method of claim 23, wherein the information indicating channel quality in a cell of interest corresponds to at least one of cell size, radio frequency reuse patterns, cell terrain features, supported transmit and receive antenna configurations, and signal transmission load conditions.

26. The method of claim 23, wherein analyzing information indicating channel quality in a cell of interest comprises determining ranges of CQI values based on the information analyzed.

27. The method of claim 26, wherein determining ranges of CQI values based on the information analyzed comprises selecting the ranges of CQI values such that they have approximately equal probabilities of occurrence.

28. The method of claim 26, wherein determining ranges of CQI values based on the information analyzed comprises selecting the ranges of CQI values such that they have approximately equal costs.

29. The method of claim 23, wherein generating at least one table of CQI values tailored to the cell of interest based on the information analyzed comprises recomposing at least one preexisting table of CQI values.

30. The method of claim 29, wherein in a first iteration, recomposing at least one preexisting table of CQI values comprises recomposing a conventional table of CQI values.

31. The method of claim 23, further comprising regenerating individual ones of the tables of CQI values based on newly analyzed information.

32. The method of claim 23, wherein the cell of interest is one of a macrocell or a microcell.

33. A computer program product for composing a table of channel quality indicator (CQI) values, comprising:

program code for analyzing information indicating channel quality in a cell of interest; and

program code for generating at least one table of CQI values tailored to the cell of interest based on the information analyzed.

34. The computer program product of claim 33, wherein the program code for analyzing information indicating channel quality in a cell of interest comprises program code for determining ranges of CQI values based on the information analyzed.

35. The computer program product of claim 34, wherein the program code for determining ranges of CQI values based on the information analyzed comprises program code for selecting the ranges of CQI values such that they have approximately equal probabilities of occurrence.

36. The computer program product of claim 34, wherein the program code for determining ranges of CQI values based on the information analyzed comprises program code for selecting the ranges of CQI values such that they have approximately equal costs.

37. The computer program product of claim 33, further comprising program code for regenerating individual ones of the tables of CQI values based on newly analyzed information.

38. A method of deploying a table of channel quality indicator (CQI) values, comprising:

retrieving a CQI table associated with a cell of interest, the CQI table comprising ranges of CQI values determined based on information indicating channel quality in the cell of interest; and

deploying the CQI table.

39. The method of claim 38, wherein deploying the CQI table comprises transmitting the CQI table via at least one dedicated control channel.

40. The method of claim 38, wherein deploying the CQI table comprises transmitting the CQI table via a broadcast channel.

41. The method of claim 40, wherein transmitting the CQI table via a broadcast channel comprises:

transmitting, via at least one dedicated control channel, a notification indicating a forthcoming CQI table transaction; and

subsequently transmitting the CQI table via the broadcast channel.

42. The method of claim 38, further comprising generating the CQI table.

43. The method of claim 42, wherein generating the CQI table comprises:

analyzing the information indicating channel quality in the cell of interest; and

generating the CQI table based on the information analyzed.

44. The method of claim 43, wherein analyzing the information indicating channel quality in the cell of interest comprises determining ranges of CQI values based on the information analyzed.

45. The method of claim 44, wherein determining ranges of CQI values based on the information analyzed comprises selecting the ranges of CQI values such that they have approximately equal probabilities of occurrence.

46. The method of claim 44, wherein determining ranges of CQI values based on the information analyzed comprises selecting the ranges of CQI values such that they have approximately equal costs.

47. The method of claim 42, further comprising regenerating the CQI table based on newly analyzed information.

48. The method of claim 38, wherein the information indicating channel quality in the cell of interest corresponds to CQI data received from one or more wireless communication devices.

49. The method of claim 38, wherein the information indicating channel quality in the cell of interest corresponds to at least one of cell size, radio frequency reuse patterns, cell terrain features, supported transmit and receive antenna configurations, and signal transmission load conditions.

50. The method of claim 38, wherein the cell of interest comprises one of a macrocell or a microcell.

51. A wireless communication device, comprising:

selection circuitry configured to retrieve a channel quality indicator (CQI) table associated with a cell of interest, the CQI table comprising ranges of CQI values determined based on information indicating channel quality in the cell of interest; and

transmit circuitry configured to deploy the CQI table.

52. The wireless communication device of claim 51, wherein the transmit circuitry is configured to deploy the CQI table by transmitting the CQI table via at least one dedicated control channel.

53. The wireless communication device of claim 51, wherein the transmit circuitry is configured to deploy the CQI table by transmitting the CQI table via a broadcast channel.

54. The wireless communication device of claim 53, wherein the transmit circuitry is configured to transmit the CQI table via a broadcast channel by transmitting, via at least one dedicated control channel, a notification indicating a forthcoming CQI table transaction and subsequently transmitting the CQI table via the broadcast channel.

55. The wireless communication device of claim 51, further comprising circuitry configured to generate the CQI table.

56. The wireless communication device of claim 55, wherein the circuitry is configured to generate the CQI table by analyzing the information indicating channel quality in the cell of interest and generating the CQI table based on the information analyzed.

57. The wireless communication device of claim 56, wherein the circuitry is configured to analyze the information indicating channel quality in the cell of interest by determining ranges of CQI values based on the information analyzed.

58. The wireless communication device of claim 57, wherein the circuitry is configured to determine ranges of CQI values based on the information analyzed by selecting the ranges of CQI values such that they have approximately equal probabilities of occurrence.

59. The wireless communication device of claim 57, wherein the circuitry is configured to determine ranges of CQI values based on the information analyzed by selecting the ranges of CQI values such that they have approximately equal costs.

60. The wireless communication device of claim 55, wherein the circuitry is further configured to regenerate the CQI table based on newly analyzed information.

61. The wireless communication device of claim 51, wherein the information indicating channel quality in the cell of interest corresponds to CQI data received from one or more different wireless communication devices.

62. The wireless communication device of claim 51, wherein the information indicating channel quality in the cell of interest corresponds to at least one of cell size, radio frequency reuse patterns, cell terrain features, supported transmit and receive antenna configurations, and signal transmission load conditions.