LONG TERM EVOLUTION MEDIUM ACCESS CONTROL PROCEDURES

• US 20090046641A1
• Filed: 08/04/2008
• Published: 02/19/2009
• Est. Priority Date: 08/13/2007
• Status: Abandoned Application

• Current Assignee: InterDigital Patent Holdings, Inc. (InterDigital, Inc.), Interdigital Technology Corporation (InterDigital, Inc.)
• Original Assignee: InterDigital Patent Holdings, Inc. (InterDigital, Inc.)
• Inventors: Terry, Stephen E., Wang, Peter S., Wang, Jin, Olvera-Hernandez, Ulises
• Application Number:
  US12/185,179
• Publication Number:
  US 20090046641A1
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04W 74/002 Transmission of channel access control information
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access
• CPC Class Codes: H04W 74/0866 using a dedicated channel for access

Abstract

Several medium access control methods are disclosed. One such method is a method for requesting an uplink resource allocation. In this method, a wireless transmit/receive unit (WTRU) receives a trigger and sends an uplink resource request to a Node B based on the trigger. The WTRU receives an uplink resource assignment and prepares for an uplink transmission using the resource assignment. The WTRU then sends an acknowledgement that the uplink resource allocation was received. A wireless transmit/receive unit according to one embodiment includes a trigger device and a processor. The trigger device is configured to receive a trigger. The processor is in communication with the trigger device, and is configured to send an uplink resource request upon receipt of the trigger, receive an uplink resource assignment, and send an acknowledgement upon receipt of the uplink resource assignment.

Claims

1. A method for requesting an uplink resource assignment, comprising:

receiving a trigger;

sending an uplink resource request;

receiving an uplink resource assignment;

preparing for an uplink transmission using the resource assignment; and

sending an acknowledgement that the resource assignment was received.

2. The method according to claim 1, wherein the trigger is at least one of:

a level of uplink data accumulation, a service priority change, a quality of service change, and failure of a previous scheduling request.

3. The method according to claim 1, wherein the resource request includes at least one of:

buffer occupancy, service priority change, power headroom indication, channel condition, type of service, and radio access bearer identifier.

4. The method according to claim 1, wherein the resource assignment includes at least one of:

start frame number of the uplink radio resource, start sub-frame number of the uplink radio resource, radio resource block allocation, duration of the radio resource allocation, channel coding, transport format combination parameters, and timing advance information.

5. The method according to claim 1, wherein the acknowledgement is an explicit acknowledgement message.

6. The method according to claim 1, wherein the acknowledgement is implicit when the uplink transmission is made.

7. A wireless transmit/receive unit (WTRU), comprising:

a trigger device configured to receive a trigger; and

a processor in communication with the trigger device, the processor configured to;

send an uplink resource request upon receipt of the trigger;

receive an uplink resource assignment; and

send an acknowledgement upon receipt of the uplink resource assignment.

8. The WTRU according to claim 7, wherein the trigger is at least one of:

a level of uplink data accumulation, a service priority change, a quality of service change, and failure of a previous scheduling request.

9. The WTRU according to claim 7, wherein the resource request includes at least one of:

buffer occupancy, service priority change, power headroom indication, channel condition, type of service, and radio access bearer identifier.

10. The WTRU according to claim 7, wherein the resource assignment includes at least one of:

start frame number of the uplink radio resource, start sub-frame number of the uplink radio resource, radio resource block allocation, duration of the radio resource allocation, channel coding, transport format combination parameters, and timing advance information.

11. The WTRU according to claim 7, wherein the acknowledgement is an explicit acknowledgement message.

12. The WTRU according to claim 7, wherein the acknowledgement is implicit when an uplink transmission is made.

13. A method for allocating uplink resources, comprising:

receiving an uplink resource request;

allocating uplink resources based on the request;

sending an uplink resource assignment; and

receiving a response indicating that the resource assignment was received.

14. The method according to claim 13, wherein the resource request includes at least one of:

buffer occupancy, service priority change, power headroom indication, channel condition, type of service, and radio access bearer identifier.

15. The method according to claim 13, wherein the resource assignment includes at least one of:

start frame number of the uplink radio resource, start sub-frame number of the uplink radio resource, radio resource block allocation, duration of the radio resource allocation, channel coding, transport format combination parameters, and timing advance information.

16. The method according to claim 13, wherein the response is an explicit acknowledgement message.

17. The method according to claim 13, wherein the response is implicit when an uplink transmission is received.

18. A method for allocating downlink resources, comprising:

receiving a trigger;

allocating downlink resources;

sending a downlink resource assignment to a wireless transmit/receive unit (WTRU); and

receiving a response from the WTRU indicating that the resource assignment was received.

19. The method according to claim 18, wherein the trigger includes at least one of:

downlink data accumulation, a data rate change, a service priority change, a quality of service change, and receipt of a scheduling request.

20. The method according to claim 18, wherein the resource assignment includes at least one of:

a downlink shared channel, a start frame number of the downlink radio resource, a start sub-frame number of the downlink radio resource, a radio resource block allocation, a duration of the downlink resource, channel coding information, and transport format combination parameters.

21. The method according to claim 18, wherein the response is an explicit acknowledgement message.

22. The method according to claim 18, wherein the response is implicit if there is subsequent uplink traffic from the WTRU.

23. A method for using a downlink resource allocation, comprising:

receiving a downlink resource assignment at a wireless transmit/receive unit (WTRU);

preparing for downlink reception; and

sending a response that the resource assignment was received.

24. The method according to claim 23, wherein the resource assignment includes at least one of:

a downlink shared channel, a start frame number of the downlink radio resource, a start sub-frame number of the downlink radio resource, a radio resource block allocation, a duration of the downlink resource, channel coding information, and transport format combination parameters.

25. The method according to claim 23, wherein the response is an explicit acknowledgement message.

26. The method according to claim 23, wherein the response is implicit if there is subsequent uplink traffic from the WTRU.

27. A method for configuring resources, comprising:

receiving a trigger;

sending a resource configuration message to a wireless transmit/receive unit (WTRU); and

receiving a response from the WTRU indicating that the resources were configured.

28. The method according to claim 27, wherein the trigger includes at least one of:

a cell resource change, a cell load change, a handover, and upon receipt of a current resource configuration of the WTRU.

29. The method according to claim 27, wherein the resource configuration message includes at least one of:

a profile identifier corresponding to a preconfigured status, a power adjustment value, a transport format change, bit rate related parameters, a synchronization timer value, timing advance information, and timing adjustment offset information.

30. The method according to claim 27, wherein the response is an explicit acknowledgement message.

31. The method according to claim 27, wherein the response is implicit if there is subsequent uplink traffic from the WTRU.

32. A method for configuring resources, comprising:

receiving a resource configuration message at a wireless transmit/receive unit (WTRU);

performing a resource configuration based on the configuration message;

sending a response indicating that the resources were configured.

33. The method according to claim 32, wherein the resource configuration message includes at least one of:

a profile identifier corresponding to a preconfigured status, a power adjustment value, a transport format change, bit rate related parameters, a synchronization timer value, timing advance information, and timing adjustment offset information.

34. The method according to claim 32, wherein the response is an explicit acknowledgement message.

35. The method according to claim 32, wherein the response is implicit if there is subsequent uplink traffic from the WTRU.

36. A method for reconfiguring a hybrid automatic repeat request (HARQ) process, comprising:

receiving a command trigger;

sending a HARQ reconfiguration command;

receiving a response that the command was received;

determining if the response includes an error trigger; and

sending an error report if the response includes the error trigger.

37. The method according to claim 36, wherein the command trigger includes at least one of:

a handover, a system load change, a radio frequency change, a channel quality indicator, and error reporting.

38. The method according to claim 36, wherein the reconfiguration command includes at least one of:

a HARQ process number, a length of time to reset the HARQ process, a maximum number of retransmissions, memory reconfiguration information, and a mapping of a logical channel identifier to the HARQ process.

39. The method according to claim 36, wherein the error trigger includes at least one of:

a negative acknowledgement being erroneously reported as an acknowledgement and reaching a maximum number of retransmissions.

40. The method according to claim 36, wherein the error report includes at least one of:

the HARQ process number, a number of errors that occurred, a number of retransmissions that were performed, and a cause of the errors.

41. A method for reconfiguring a hybrid automatic repeat request (HARQ) process, comprising:

receiving a HARQ reconfiguration command;

performing the HARQ reconfiguration command; and

sending a response that the command was received.

42. The method according to claim 41, wherein the reconfiguration command includes at least one of:

a HARQ process number, a length of time to reset the HARQ process, a maximum number of retransmissions, memory reconfiguration information, and a mapping of a logical channel identifier to the HARQ process.

43. The method according to claim 41, wherein the response includes an error trigger, the error trigger including at least one of:

a negative acknowledgement being erroneously reported as an acknowledgement and reaching a maximum number of retransmissions.

44. The method according to claim 43, further comprising:

receiving an error report, the error report including at least one of;

the HARQ process number, a number of errors that occurred, a number of retransmissions that were performed, and a cause of the errors.

45. A method for uplink timing alignment, comprising:

receiving a trigger;

sending an uplink timing alignment request;

receiving a timing alignment command, including a timing alignment value;

applying the timing alignment value;

sending a response that the timing alignment command was received.

46. The method according to claim 45, wherein the trigger includes at least one of:

a timing alignment timer expires, a change in channel conditions, a handover, a wireless transmit/receive unit mobility change, and whether there is any uplink traffic available.

47. The method according to claim 45, wherein the timing alignment command includes at least one of:

the timing alignment value, a duration that the timing alignment value is valid, and whether an explicit acknowledgement is required.

48. The method according to claim 45, wherein the response includes an explicit acknowledgement that the timing adjustment command was received.

49. The method according to claim 45, wherein the response is implicit if there is subsequent uplink traffic.

50. A method for uplink timing alignment, comprising:

receiving an uplink timing alignment request;

performing a timing estimation process based on the timing alignment request to determine a timing alignment value;

sending a timing alignment command, including the timing alignment value; and

receiving a response that the timing alignment command was received.

51. The method according to claim 50, wherein the timing alignment command includes at least one of:

the timing alignment value, a duration that the timing alignment value is valid, and whether an explicit acknowledgement is required.

52. The method according to claim 50, wherein the response is an explicit acknowledgement that the timing adjustment command was received.

53. The method according to claim 50, wherein the response is implicit if there is subsequent uplink traffic.

54. A method for configuring discontinuous reception (DRX) and discontinuous transmission (DTX) at a wireless transmit/receive unit (WTRU), comprising:

receiving a trigger;

sending a DRX/DTX request;

receiving a DRX/DTX assignment; and

applying the DRX/DTX assignment.

55. The method according to claim 54, wherein the trigger includes at least one of:

whether the WTRU has a continuous downlink traffic demand and whether the WTRU needs to be in a power saving mode.

56. The method according to claim 54, wherein the request includes at least one of:

active WTRU service types, a current uplink traffic load, an existing DRX pattern and duration, a service type performed by the WTRU, and current channel conditions.

57. The method according to claim 54, wherein the assignment includes at least one of:

a number of DRX/DTX stages, a number of DRX/DTX levels, a stage change triggering timer value, a stage change triggering event value, one or more DRX/DTX patterns, and a duration for each pattern.

58. The method according to claim 54, further comprising:

sending a DRX/DTX confirmation to indicate that the DRX/DTX assignment was received.

59. A method for configuring discontinuous reception (DRX) and discontinuous transmission (DTX), comprising:

receiving a DRX/DTX request from a wireless transmit/receive unit (WTRU);

determining a DRX/DTX configuration based on the request; and

sending a DRX/DTX assignment to the WTRU.

60. The method according to claim 59, wherein the request includes at least one of:

active WTRU service types, a current uplink traffic load, an existing DRX pattern and duration, a service type performed by the WTRU, and current channel conditions.

61. The method according to claim 59, wherein the assignment includes at least one of:

a number of DRX/DTX stages, a number of DRX/DTX levels, a stage change triggering timer value, a stage change triggering event value, one or more DRX/DTX patterns, and a duration for each pattern.

62. The method according to claim 59, further comprising:

receiving a DRX/DTX confirmation from the WTRU to indicate that the DRX/DTX assignment was received.

63. A method for allocating a random access channel (RACH) resource, comprising:

receiving a trigger;

sending a resource allocation to a wireless transmit/receive unit (WTRU); and

receiving a response from the WTRU, whereby the response provides an indication that the resource allocation was applied.

64. The method according to claim 63, wherein the trigger is at least one of:

initiation of a non-contention based handover, uplink synchronization maintenance, radio link connection re-establishment, an uplink measurement report, and changes to the RACH values in a system information block.

65. The method according to claim 63, wherein the resource allocation includes at least one of:

a dedicated RACH signature, a preamble for the time domain, an access resource for the frequency domain, a pattern change of the resource, and a response command field.

66. The method according to claim 65, wherein the preamble for the time domain includes at least one of:

a RACH access subframe number, a number of subframes that the preamble is valid, and a frequency of how often the RACH opportunity is available.

67. The method according to claim 65, wherein the access resource for the frequency domain includes at least one of:

a sub-carrier location and a specific RACH if more than one RACH is allocated.

68. The method according to claim 65, wherein the pattern change of the resource includes a frequency hopping pattern.

69. The method according to claim 63, wherein the response is implicit when the WTRU accesses the RACH.

70. A method for using a random access channel (RACH) resource allocation, comprising:

receiving a RACH resource allocation, the resource allocation including access parameters;

applying the access parameters; and

accessing the RACH, whereby an implicit acknowledgement is sent, indicating that the resource allocation was received.

71. The method according to claim 70, wherein the access parameters include at least one of:

a dedicated RACH signature, a preamble for the time domain, an access resource for the frequency domain, a pattern change of the resource, and a response command field.

72. The method according to claim 71, wherein the preamble for the time domain includes at least one of:

a RACH access subframe number, a number of subframes that the preamble is valid, and a frequency of how often the RACH opportunity is available.

73. The method according to claim 71, wherein the access resource for the frequency domain includes at least one of:

a sub-carrier location and a specific RACH if more than one RACH is allocated.

74. The method according to claim 71, wherein the pattern change of the resource includes a frequency hopping pattern.

75. A method for performing a resource inquiry, comprising:

receiving a trigger;

sending a resource inquiry to a wireless transmit/receive unit (WTRU); and

receiving resource information from the WTRU.

76. The method according to claim 75, wherein the trigger includes at least one of:

a resource configuration status of the WTRU is needed and certain measurement events.

77. The method according to claim 75, wherein the resource inquiry includes an indication of what WTRU resource information is needed.

78. The method according to claim 75, wherein the resource information includes at least one of:

buffer occupancy, channel load, power control, power headroom value, and a currently configured transport format.

79. The method according to claim 75, further comprising:

starting a response timer when the resource inquiry is sent; and

resending the resource inquiry if the resource information is not received from the WTRU before the response timer expires.

80. The method according to claim 79, wherein the resource inquiry is resent up to a predetermined number of times.

81. A method for providing resource information, comprising:

receiving a resource inquiry from a Node B, the resource inquiry including requested information; and

providing the requested information to the Node B.

82. A method for discontinuous reception (DRX) and discontinuous transmission (DTX) assignment, comprising:

receiving a trigger; and

sending a DRX/DTX assignment to a wireless transmit/receive unit (WTRU).

83. The method according to claim 82, wherein the trigger includes at least one of:

a current WTRU context, traffic conditions of the WTRU, receipt of a DRX/DTX request from the WTRU.

84. The method according to claim 83, wherein the assignment includes at least one of:

a number of DRX/DTX stages, a number of DRX/DTX levels, a stage change triggering timer value, a stage change triggering event value, one or more DRX/DTX patterns, and a duration for each pattern.

85. The method according to claim 82, further comprising:

receiving a confirmation from the WTRU that the DRX/DTX assignment was received.

86. A method for applying a discontinuous reception (DRX) and discontinuous transmission (DTX) assignment, comprising:

receiving the DRX/DTX assignment, the assignment including at least one of;

a number of DRX/DTX stages, a number of DRX/DTX levels, a stage change triggering timer value, a stage change triggering event value, one or more DRX/DTX patterns, and a duration for each pattern; and

applying the DRX/DTX assignment.

87. The method according to claim 86, further comprising:

sending a confirmation that the DRX/DTX assignment was received.

88. A method for measurement gap configuration at a wireless transmit/receive unit (WTRU), comprising:

receiving a trigger;

sending a measurement gap request;

receiving a measurement gap assignment; and

applying the measurement gap assignment.

89. The method according to claim 88, wherein the trigger includes at least one of:

a discontinuous reception cycle change, a measurement load change upon a radio frequency change, and a WTRU state change.

90. The method according to claim 88, wherein the request includes at least one of:

a current inter-frequency measurement load, a current inter-radio access technology measurement load, and a current discontinuous reception cycle.

91. The method according to claim 88, wherein the assignment includes at least one of:

a measurement gap pattern, a measurement gap duration, and measurement purposes.

92. The method according to claim 88, further comprising:

sending a confirmation that the measurement gap assignment was received.

93. A method for measurement gap configuration, comprising:

receiving a measurement gap request from a wireless transmit/receive unit (WTRU);

determining a measurement gap configuration based on the request; and

sending a measurement gap assignment to the WTRU, the assignment including the measurement gap configuration.

94. The method according to claim 93, wherein the request includes at least one of:

a current inter-frequency measurement load, a current inter-radio access technology measurement load, and a current discontinuous reception cycle.

95. The method according to claim 93, wherein the assignment includes at least one of:

a measurement gap pattern, a measurement gap duration, and measurement purposes.

96. The method according to claim 93, further comprising:

receiving a confirmation from the WTRU that the measurement gap assignment was received.

97. A method for measurement gap assignment, comprising:

receiving a trigger; and

sending a measurement gap assignment to a wireless transmit/receive unit (WTRU).

98. The method according to claim 97, wherein the trigger includes at least one of:

a current WTRU context, traffic conditions of the WTRU, and receipt of a measurement gap request from the WTRU.

99. The method according to claim 97, wherein the assignment includes at least one of:

a measurement gap pattern, a measurement gap duration, and measurement purposes.

100. The method according to claim 97, further comprising:

receiving a confirmation from the WTRU that the measurement gap assignment was received.

101. A method for applying a measurement gap assignment, comprising:

receiving the measurement gap assignment, the assignment including at least one of;

a measurement gap pattern, a measurement gap duration, and measurement purposes; and

applying the measurement gap assignment.

102. The method according to claim 101, further comprising:

sending a confirmation that the measurement gap assignment was received.

103. A method for discontinuous reception (DRX) and discontinuous transmission (DTX) inquiry by a Node B, comprising:

receiving a trigger;

sending an inquiry to a wireless transmit/receive unit (WTRU); and

receiving a response from the WTRU.

104. The method according to claim 103, wherein the trigger includes at least one of:

current DRX/DTX configuration information for the WTRU is not available and a predetermined measurement event.

105. The method according to claim 103, wherein the inquiry includes specific DRX/DTX values that are needed by the Node B.

106. The method according to claim 103, wherein the response includes at least one of:

a number of DRX/DTX stages, a number of DRX/DTX levels, a stage change triggering timer value, a stage change triggering event value, one or more DRX/DTX patterns, and a duration for each pattern.

107. The method according to claim 103, further comprising:

starting a response timer when the inquiry is sent; and

resending the inquiry if no response is received from the WTRU before the response timer expires.

108. The method according to claim 107, wherein the inquiry is resent up to a predetermined number of times.