Method and apparatus for selecting and reselecting an uplink primary carrier

Abstract

A method and apparatus are described for using an uplink (UL) primary carrier for long term evolution-advanced (LTE-A) to support hybrid automatic repeat request (HARQ) feedback, a channel quality indicator (CQI), a scheduling request (SR), power headroom, and at least one buffer status report in the context of asymmetrical deployment and symmetrical deployment.

1 . A method, implemented by a wireless transmit/receive unit (WTRU), of reselecting an uplink (UL) primary carrier, the method comprising:
 configuring the WTRU to use a particular UL carrier as a first UL primary carrier;   receiving a first radio resource control (RRC) message;   decoding the first RRC message;   sending a scheduling request (SR) on a second UL primary carrier;   initiating operation on the second UL primary carrier;   receiving a UL grant; and   sending a second RRC message acknowledging receipt of the first RRC message on a physical uplink shared channel (PUSCH) allocated by the UL grant.   
     
     
         2 . The method of  claim 1  further comprising:
 transmitting a hybrid automatic repeat request (HARQ) positive acknowledgement (ACK) or a negative acknowledgement (NACK) over the second UL primary carrier to provide feedback pertaining to a particular downlink shared channel (DL-SCH).   
     
     
         3 . The method of  claim 1  further comprising:
 transmitting a channel quality indicator (CQI) over the second UL primary carrier to provide feedback pertaining to a particular downlink shared channel (DL-SCH).   
     
     
         4 . The method of  claim 1  wherein feedback pertaining to a particular downlink shared channel (DL-SCH) is transmitted over a physical uplink control channel (PUCCH) of the second UL primary carrier. 
     
     
         5 . The method of  claim 1  wherein multiple hybrid automatic repeat request (HARQ) feedbacks resulting from a received physical downlink shared channel (PDSCH) are consolidated and transmitted on physical uplink control channel (PUCCH) resources of the second UL primary carrier. 
     
     
         6 . The method of  claim 1  wherein the first RRC message indicates that a one-direction intra-cell handover should be initiated. 
     
     
         7 . The method of  claim 1  wherein the first RRC message includes a field that identifies the second UL primary carrier. 
     
     
         8 . The method of  claim 1  wherein the first RRC message includes a field indicating assigned physical uplink control channel (PUCCH) resources. 
     
     
         9 . The method of  claim 1  wherein the first RRC message includes an RRC field indicating that the first RRC message constitutes a one-direction UL handover. 
     
     
         10 . The method of  claim 1  wherein the SR is sent on the second UL primary carrier using new resources indicated in the first RRC message. 
     
     
         11 . A method, implemented by a wireless transmit/receive unit (WTRU), of reselecting an uplink (UL) primary carrier, the method comprising:
 configuring the WTRU to use a particular UL carrier as a first UL primary carrier;   receiving a first radio resource control (RRC) message;   decoding the first RRC message;   initiating a random access channel (RACH) procedure on a second UL primary carrier;   transmitting a preamble;   receiving a random access response message;   initiating operation on the second UL primary carrier;   receiving a UL grant; and   sending a second RRC message acknowledging receipt of the first RRC message on a physical uplink shared channel (PUSCH) allocated by the UL grant.   
     
     
         12 . The method of  claim 11  wherein the first RRC message indicates that a one-direction intra-cell handover should be initiated. 
     
     
         13 . The method of  claim 11  wherein the first RRC message includes a field that identifies the second UL primary carrier. 
     
     
         14 . The method of  claim 11  wherein the first RRC message includes a field indicating assigned physical uplink control channel (PUCCH) resources. 
     
     
         15 . The method of  claim 11  wherein the first RRC message includes a field indicating RACH dedicated resources. 
     
     
         16 . The method of  claim 11  wherein the first RRC message includes an RRC field indicating that the first RRC message constitutes a one-direction UL handover. 
     
     
         17 . The method of  claim 11  wherein the RACH message includes timing alignment or timing advance information. 
     
     
         18 . A method, implemented by a wireless transmit/receive unit (WTRU), of reselecting an uplink (UL) primary carrier, the method comprising:
 configuring the WTRU to use a particular UL carrier as a first UL primary carrier;   receiving a first radio resource control (RRC) message;   decoding the first RRC message;   waiting for a predefined idle period to expire;   receiving a UL grant;   sending a second RRC message acknowledging receipt of the first RRC message on a physical uplink shared channel (PUSCH) allocated by the UL grant; and   initiating operation on a second UL primary carrier.   
     
     
         19 . A method, implemented by a wireless transmit/receive unit (WTRU), of reselecting an uplink (UL) primary carrier, the method comprising:
 configuring the WTRU to use a particular UL carrier as a first UL primary carrier;   receiving a medium access control (MAC) control element (CE) primary change command;   a MAC layer in the WTRU processing the MAC CE primary change command and informing a physical (PHY) layer in the WTRU about the location of a second UL primary carrier;   at a first subframe, the PHY layer sending a first positive acknowledgement (ACK) via the first UL primary carrier;   the MAC layer processing the same MAC CE primary change command as was previously processed; and   at a second subframe, the PHY layer sending a second ACK via the second UL primary carrier.   
     
     
         20 . A wireless transmit/receive unit (WTRU) for reselecting an uplink (UL) primary carrier, the WTRU comprising:
 a processor configured to use a particular UL carrier as a first UL primary carrier;   a receiver configured to receive and decode a first radio resource control (RRC) message and receive a UL grant; and   a transmitter configured to transmit a scheduling request (SR) on a second UL primary carrier, and transmit a second RRC message acknowledging receipt of the first RRC message on a physical uplink shared channel (PUSCH) allocated by the UL grant.   
     
     
         21 . The WTRU of  claim 20  further comprising:
 a transmitter configured to transmit a hybrid automatic repeat request (HARQ) positive acknowledgement (ACK) or a negative acknowledgement (NACK) over the second UL primary carrier to provide feedback pertaining to a particular downlink shared channel (DL-SCH).   
     
     
         22 . The WTRU of  claim 20  further comprising:
 a transmitter configured to transmit a channel quality indicator (CQI) over the second UL primary carrier to provide feedback pertaining to a particular downlink shared channel (DL-SCH).   
     
     
         23 . The WTRU of  claim 20  wherein feedback pertaining to a particular downlink shared channel (DL-SCH) is transmitted over a physical uplink control channel (PUCCH) of the second UL primary carrier. 
     
     
         24 . The WTRU of  claim 20  wherein multiple hybrid automatic repeat request (HARQ) feedbacks resulting from a received physical downlink shared channel (PDSCH) are consolidated and transmitted on physical uplink control channel (PUCCH) resources of the second UL primary carrier. 
     
     
         25 . The WTRU of  claim 20  wherein the first RRC message indicates that a one-direction intra-cell handover should be initiated. 
     
     
         26 . The WTRU of  claim 20  wherein the first RRC message includes a field that identifies the second UL primary carrier. 
     
     
         27 . The WTRU of  claim 20  wherein the first RRC message includes a field indicating assigned physical uplink control channel (PUCCH) resources. 
     
     
         28 . The WTRU of  claim 20  wherein the first RRC message includes an RRC field indicating that the first RRC message constitutes a one-direction UL handover. 
     
     
         29 . The WTRU of  claim 20  wherein the SR is sent on the second UL primary carrier using new resources indicated in the first RRC message. 
     
     
         30 . A wireless transmit/receive unit (WTRU) for reselecting an uplink (UL) primary carrier, the WTRU comprising:
 a processor configuring the WTRU to use a particular UL carrier as a UL primary carrier, and initiate a random access channel (RACH) procedure on a second UL primary carrier;   a receiver configured to receive and decode a first radio resource control (RRC) message, receive a random access response message and receive a UL grant; and   a transmitter configured to transmit a preamble, and transmit a second RRC message acknowledging receipt of the first RRC message on a physical uplink shared channel (PUSCH) allocated by the UL grant.   
     
     
         31 . The WTRU of  claim 30  wherein the first RRC message indicates that a one-direction intra-cell handover should be initiated. 
     
     
         32 . The WTRU of  claim 30  wherein the first RRC message includes a field that identifies the second UL primary carrier. 
     
     
         33 . The WTRU of  claim 30  wherein the first RRC message includes a field indicating assigned physical uplink control channel (PUCCH) resources. 
     
     
         34 . The WTRU of  claim 30  wherein the first RRC message includes a field indicating RACH dedicated resources. 
     
     
         35 . The WTRU of  claim 30  wherein the first RRC message includes an RRC field indicating that the first RRC message constitutes a one-direction UL handover. 
     
     
         36 . The WTRU of  claim 30  wherein the RACH message includes timing alignment or timing advance information. 
     
     
         37 . A wireless transmit/receive unit (WTRU) for reselecting an uplink (UL) primary carrier, the WTRU comprising:
 a receiver configured to receive a medium access control (MAC) control element (CE) primary change command; and   a processor configured to use a particular UL carrier as a first UL primary carrier;   a physical (PHY) layer configured to send a first positive acknowledgement (ACK) via the first UL primary carrier at a first subframe, and send a second ACK via a second UL primary carrier at a second subframe; and   a medium access control (MAC) layer configured to process the MAC CE primary change command, inform the PHY layer about the location of the second UL primary carrier, and process the same MAC CE primary change command as was previously processed.   
     
     
         38 . The WTRU of  claim 37  wherein the PHY layer and the MAC layer reside in the processor.