CONTROL SIGNALING IN LTE CARRIER AGGREGATION

• US 20130163543A1
• Filed: 12/22/2012
• Published: 06/27/2013
• Est. Priority Date: 12/22/2011
• Status: Active Grant

• Current Assignee: InterDigital Patent Holdings, Inc. (InterDigital, Inc.)
• Original Assignee: InterDigital Patent Holdings, Inc. (InterDigital, Inc.)
• Inventors: Freda, Martino, Gauvreau, Jean-Louis, Di Girolamo, Rocco, Dai, Yuying, Beluri, Mihaela C.
• Granted Patent: US 9,363,797 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0041 Frequency-non-contiguous
• CPC Class Codes: H04L 5/0092 Indication of how the channel is divided
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 72/04 Wireless resource allocation
• CPC Class Codes: H04W 72/20 Control channels or signalling for resource management
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal

Abstract

Methods and devices may be provided for aggregating component carriers in the licensed spectrum with at least one component carriers in the licensed exempt spectrum. Control information may be processed in a wireless transmit/receive unit (WTRU) while receiving and sending information on a primary component carrier (PCC) and a supplementary component carrier (SuppCC). A PCC subframe with a control portion and a data portion may be received. Resource assignment information associated with a downlink shared channel on the PCC may be embedded in the control portion of the subframe. Based on the resource assignment information on the PCC, resource assignment information associated with a downlink shared channel on the SuppCC may be identified in the data portion of the PCC subframe. A SuppCC subframe of the shared channel on the SuppCC may be processed as per the identified resource assignment information associated with the downlink shared channel on the SuppCC.

Claims

1. A wireless transmit receive unit (WTRU) configured to process control information when receiving and sending information on a primary component carrier (PCC) and a supplementary component carrier (SuppCC), the WTRU comprising:

a processor configured to;

receive a first PCC subframe, the first PCC subframe comprising a control portion and a data portion, the control portion comprising resource assignment information associated with a downlink shared channel on the PCC;

identify in the data portion of the first PCC subframe, resource assignment information associated with a downlink shared channel on the SuppCC based on the resource assignment information associated with the downlink shared channel on the PCC; and

process a first SuppCC subframe of the shared channel on the SuppCC in accordance with the identified resource assignment information associated with the downlink shared channel on the SuppCC.

2. The WTRU of claim 1, the processor is further configured to:

receive a second PCC subframe, the second PCC subframe comprising a control portion and a data portion, the control portion comprising resource assignment information associated with the downlink shared channel on the PCC;

identify, in the data portion of the second PCC subframe, resource assignment information associated with an uplink shared channel on the SuppCC based on the resource assignment information associated with the downlink shared channel on the PCC; and

send information in, a second SuppCC subframe of the shared channel on the SuppCC in accordance with the identified resource assignment information associated with the uplink shared channel on the SuppCC.

3. The WTRU of claim 2, wherein the first SuppCC subframe is subsequent to the first PCC subframe, and the second SuppCC is subsequent to the second PCC subframe.

4. The WTRU of claim 2, wherein the resource assignment information associated with the uplink shared channel on the SuppCC comprises an uplink grant associated with the second SuppCC subframe on the uplink shared channel on SuppCC.

5. The WTRU of claim 4, further configured to send the uplink grant on the first PCC subframe or the first SuppCC subframe when a second PCC or the SuppCC is a TDD component carrier and the second PCC or the SuppCC subframe is an uplink subframe.

6. The WTRU of claim 1, wherein the PCC comprises a frequency division duplex (FDD) component carrier or a time division duplex (TDD) component carrier, and the SuppCC comprises a frequency division duplex (FDD) component carrier or a time division duplex (TDD) component carrier.

7. A wireless transmit receive unit (WTRU) configured to decode control information, the WTRU comprising:

a processor configured to

determine a first search space comprising a first plurality of Physical Downlink Control Channel (PDCCH) candidates for decoding control information using a first downlink control information (DCI) format type;

determine a second search space comprising a second plurality of PDCCH candidates for decoding the control information using a second DCI format type, wherein the first plurality of PDCCH candidates and the second plurality of PDCCH candidates are distinct;

perform blind decoding of the first plurality of PDCCH candidates based on the first DCI format type; and

perform blind decoding of the second plurality of PDCCH candidates based on the second DCI format type.

8. The WTRU of claim 7, wherein a first PDCCH candidate and a second PDCCH candidate are distinct when the first and the second candidates have at least one of:

distinct begin points, distinct end points or distinct aggregation level modes.

9. The WTRU of claim 7 wherein a carrier indicator field (CIF) size associated with the first DCI format type is different than the CIF size associated with the second DCI format type.

10. The WTRU of claim 7, wherein the processor is configured to dynamically derive PDCCH candidates for the first search space and the second search space based on a CIF corresponding to the SuppCC.

11. The WTRU of claim 7, wherein the first and the second plurality of PDCCH candidates are defined based on traffic load as indicated by a radio resource control (RRC) signal.

12. The WTRU of claim 7, wherein the first DCI format type is associated with a FDD carrier and the second DCI format type is associated with a TDD carrier.

13. A method for search space reconfiguration, the method comprising:

sending from a wireless transmit receive unit (WTRU) a measurement related to a supplementary channel indicating a signal to interference plus noise ratio (SINR) value;

receiving at the WTRU, based on the SINR, a search space reconfiguration signal (SSRS) indicating a change in an aggregation level mode of the WTRU at a sub-frame, wherein the SSRS is in response to the measurement; and

changing, at the WTRU, at the sub-frame, the aggregation level mode from a first order aggregation level to a second order aggregation level based on the SSRS.

14. The method of claim 13, wherein the first order aggregation level is lower than the second order aggregation level.

15. The method of claim 13, wherein the change in the aggregation level mode from the first order aggregation level to the second order aggregation level comprises combining candidates of the first order aggregation level to create candidates of the second order aggregation level.

16. The method of claim 13, further comprising sending an acknowledgment signal in response to the SSRS.

17. The method of claim 13, wherein the SSRS comprises a medium access control-control element (MAC-CE).

18. The method of claim 13, wherein the SSRS is periodically received by the WTRU via a broadcast signal.

19. The method of claim 13, wherein the SSRS is received via a radio resource control (RRC) signal.

20. The method of claim 13, wherein changing the aggregation level mode from the first order aggregation level to the second order aggregation level further comprises:

measuring an averaged signal and interference plus noise ratio (SINR) value for the WTRU over an averaging interval;

comparing the averaged SINR value with a threshold SINR value;

sending to the WTRU an indication when to operate in an extended aggregation level, when the averaged SINR value for the WTRU drops a predetermined value below the threshold SINR value; and

sending to the WTRU an indication when to operate in a normal aggregation level mode, when the averaged SINR value for the WTRU reaches a predetermined value above the threshold SINR value.