Downlink Control Information Set Switching When Using Carrier Aggregation

• US 20130010709A1
• Filed: 04/26/2012
• Published: 01/10/2013
• Est. Priority Date: 10/30/2009
• Status: Active Grant

• Current Assignee: Malikie Innovations Limited (Key Patent Innovations Limited)
• Original Assignee: Research In Motion Limited (Blackberry Limited)
• Inventors: Earnshaw, Andrew Mark, Heo, Youn Hyoung, Cai, Zhijun, Fong, Mo-Han, Xu, Hua
• Granted Patent: US 8,780,841 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04L 27/2602 Signal structure
• CPC Class Codes: H04L 5/001 the frequencies being arranged in component carriers
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04L 5/0055 Physical resource allocation for ACK/NACK for physical mapping arrangements in ARQ protocols H04L1/1861
• CPC Class Codes: H04L 5/0091 Signaling for the administration of the divided path
• CPC Class Codes: H04L 5/14 Two-way operation using the same type of signal, i.e. duplex
• CPC Class Codes: H04W 72/0453 Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal

Abstract

A method and apparatus for reconfiguring a user equipment configured for multi-carrier operation from a first downlink control information set to a second downlink control information set while carrier aggregation is being used, including receiving a physical downlink control channel with downlink control information formats containing a carrier indicator field.

Claims

1. A method comprising:

reconfiguring from a first downlink control information (DCI) set to a second DCI set while carrier aggregation is being used.

2. The method of claim 1 wherein reconfiguring includes:

reconfiguring a user equipment (UE) for multi-carrier operation, including receiving a physical downlink control channel (PDCCH) with DCI formats containing a carrier indicator field (CIF).

3. The method of claim 1 wherein the first DCI set comprises a set of DCI formats having a first carrier indicator field (CIF) size, wherein the second DCI set comprises a set of DCI formats having a second, different CIF size, and wherein reconfiguring comprises changing from the first CIF size to the second CIF size and wherein the first CIF size or the second CIF size may be equal to zero.

4. The method of claim 1 further comprising:

determining an activation time related to the reconfiguring.

5. The method of claim 4 wherein the activation time is included as part of a radio resource control (RRC) command that orders the reconfiguring, and wherein the activation time comprises a system frame number (SFN) and subframe offset within the same radio frame associated with the SFN.

6. The method of claim 1 further comprising:

transmitting DCI formats corresponding to both the first DCI set and the second DCI set during a time period after a reconfiguring command is transmitted.

7. The method of claim 1 further comprising:

specifying that at least one common DCI format size is included in both the first DCI set and the second DCI set.

8. The method of claim 1 further comprising:

a user equipment (UE) monitoring both the first DCI set and the second DCI set until at least one of the following conditions has been satisfied;

     1) receiving a radio resource control (RRC) command to stop monitoring the first DCI set, and

     2) receiving a predetermined number of DCI formats that unambiguously belong to the second DCI set; and

thereafter the UE monitoring only the second DCI set.

9. The method of claim 8 wherein the predetermined number is one of a fixed number and a configurable number received from an access node.

10. The method of claim 8 further comprising:

specifying which DCI format is to be monitored when a size of a DCI format in the first DCI set equals a size of a different DCI format in the second DCI set.

11. The method of claim 1 further comprising:

when a size of a DCI format in the first DCI set equals a size of a different DCI format in the second DCI set avoiding monitoring the DCI format in the second DCI set after the reconfiguring until a radio resource control (RRC) message is received at a user equipment (UE).

12. The method of claim 1 further comprising:

when a size of a DCI format in the first DCI set equals a size of a different DCI format in the second DCI set, including additional padding bits for the DCI format in the second DCI set.

13. A user equipment (UE) comprising a processor configured to:

reconfigure from a first downlink control information (DCI) set to a second DCI set while carrier aggregation is being used.

14. The UE of claim 13 wherein the UE is configured for multi-carrier operation, and the processor is further configured to:

receive a physical downlink control channel (PDCCH) with DCI formats containing a carrier indicator field (CIF).

15. The UE of claim 13 wherein the first DCI set comprises a set of DCI formats having a first carrier indicator field (CIF) size, wherein the second DCI set comprises a set of DCI formats having a second, different CIF size, and wherein reconfigure comprises changing from the first CIF size to the second CIF size and wherein the first CIF size or the second CIF size may be equal to zero.

16. The UE of claim 13 wherein the processor is further configured to:

receive an indication of an activation time related to the reconfigure.

17. The UE of claim 16 wherein the activation time is included as part of a radio resource control (RRC) command that orders the reconfigure, and wherein the activation time comprises a system frame number (SFN) and subframe offset within the same radio frame associated with the SFN.

18. The UE of claim 13, wherein the processor is further configured to:

receive DCI formats corresponding to both the first DCI set and the second DCI set during a time period after a reconfiguring command is transmitted.

19. The UE of claim 13, wherein the processor is further configured to:

receive at least one common DCI format size that is included in both the first DCI set and the second DCI set.

20. The UE of claim 13, wherein the processor is further configured to:

monitor both the first DCI set and the second DCI set until at least one of the following conditions has been satisfied;

     1) receiving a radio resource control (RRC) command to stop monitoring the first DCI set, and

     2) receiving a predetermined number of DCI formats that unambiguously belong to the second DCI set; and

thereafter monitor only the second DCI set.

21. The UE of claim 20, wherein the predetermined number is one of a fixed number and a configurable number received from an access node.

22. The UE of claim 20, wherein the processor is further configured to:

determine which DCI format is to be monitored when a size of a DCI format in the first DCI set equals a size of a different DCI format in the second DCI set.

23. The UE of claim 13, wherein the processor is further configured to:

when a size of a DCI format in the first DCI set equals a size of a different DCI format in the second DCI set, avoid monitoring the DCI format in the second DCI set after the reconfigure until a radio resource control (RRC) message is received.

24. The UE of claim 13, wherein the processor is further configured to:

when a size of a DCI format in the first DCI set equals a size of a different DCI format in the second DCI set, include additional padding bits for the DCI format in the second DCI set.

25. An access device comprising a processor configured to:

reconfigure a user equipment (UE) from a first downlink control information (DCI) set to a second DCI set while carrier aggregation is being used.

26. The access device of claim 25 wherein the processor is further configured to:

transmit a physical downlink control channel (PDCCH) with DCI formats containing a carrier indicator field (CIF).

27. The access device of claim 25 wherein the first DCI set comprises a set of DCI formats having a first carrier indicator field (CIF) size, wherein the second DCI set comprises a set of DCI formats having a second, different CIF size, and wherein the reconfigure comprises changing from the first CIF size to the second CIF size and wherein the first CIF size or the second CIF size may be equal to zero.

28. The access device of claim 25 wherein the processor is further configured to:

determine an activation time related to the reconfigure.

29. The access device of claim 28 wherein the activation time is included as part of a radio resource control (RRC) command that orders the reconfigure, and wherein the activation time comprises a system frame number (SFN) and subframe offset within the same radio frame associated with the SFN.

30. The access device of claim 25 wherein the processor is further configured to:

transmit DCI formats corresponding to both the first DCI set and the second DCI set during a time period after a reconfigure command is transmitted.

31. The access device of claim 25 wherein the processor is further configured to:

specify that at least one common DCI format size is included in both the first DCI set and the second DCI set.

32. The access device of claim 25 wherein the processor is further configured to:

transmit a radio resource control (RRC) command to the UE to stop monitoring the first DCI set; and

transmit a predetermined number of DCI formats that unambiguously belong to the second DCI set such that the UE monitors only the second DCI set.

33. The access device of claim 32 wherein the predetermined number is one of a fixed number and a configurable number transmitted by the access node.

34. The access device of claim 32 wherein the processor is further configured to:

specify which DCI format is to be monitored when a size of a DCI format in the first DCI set equals a size of a different DCI format in the second DCI set.

35. The access node of claim 25 wherein the processor is further configured to:

when a size of a DCI format in the first DCI set equals a size of a different DCI format in the second DCI set, include additional padding bits for the DCI format in the second DCI set.