Communication on licensed and unlicensed bands

Abstract

To perform a random access procedure on licensed and unlicensed carriers, a user equipment may receive a system information block (SIB) on a downlink carrier in a first carrier frequency, where the SIB includes configuration information for a first uplink carrier and a second uplink carrier, and transmit a physical random access channel (PRACH) either on the first uplink carrier or on the second uplink carrier. A response to the transmitted PRACH received by the user equipment on a downlink carrier may schedule transmission of data channel. The SIB preferably includes configuration information for determining a power for the PRACH transmission on the first and second uplink carriers. The frequency band of the downlink carrier is same as the frequency band of the first uplink carrier and is different than that of the second uplink carrier, which has a frequency lower than the frequency of the first UL carrier.

What is claimed is: 
     
         1 . A method for a user equipment (UE) to transmit a physical uplink shared channel (PUSCH), the method comprising:
 receiving a physical downlink control channel (PDCCH) that provides a downlink control information (DCI) format, wherein:
 the DCI format schedules a PUSCH transmission, 
 the DCI format includes a first field indicating a cell, and 
 the DCI format includes a second field indicating a carrier of the cell; and 
   transmitting the PUSCH on the carrier of the cell.   
     
     
         2 . The method of  claim 1 , further comprising:
 receiving a system information block (SIB), wherein the SIB includes configuration information for a first uplink (UL) carrier and for a second UL carrier.   
     
     
         3 . The method of  claim 1 , wherein the second field includes one bit. 
     
     
         4 . The method of  claim 1 , wherein:
 the first field is included in a DCI format that schedules a physical downlink shared channel (PDSCH) reception, and   the second field in never included in the DCI format that schedules a PDSCH reception.   
     
     
         5 . The method of  claim 1 , wherein:
 the cell includes one downlink (DL) carrier for reception by the UE,   the cell includes two uplink (UL) carriers for transmission from the UE, and   the transmission from the UE is only on one of the two UL carriers at a given time.   
     
     
         6 . The method of  claim 1 , wherein:
 the cell includes one downlink (DL) carrier for reception by the UE,   the cell includes two uplink (UL) carriers for transmission from the UE,   the DL carrier and the first of the two UL carriers are in a first frequency band, and   the second of the two UL carriers is in a second frequency band.   
     
     
         7 . The method of  claim 6 , wherein the second frequency band is at a lower frequency that the first frequency band. 
     
     
         8 . A user equipment (UE), comprising:
 a transceiver configured to receive a physical downlink control channel (PDCCH) that provides a downlink control information (DCI) format, wherein:   the DCI format schedules a PUSCH transmission,   the DCI format includes a first field indicating a cell, and   the DCI format includes a second field indicating a carrier of the cell, wherein the transceiver is further configured to transmit the PUSCH on the carrier of the cell.   
     
     
         9 . The UE of  claim 8 , wherein:
 the transceiver is further configured to receive a system information block (SIB), and   the SIB includes configuration information for a first uplink (UL) carrier and for a second UL carrier.   
     
     
         10 . The UE of  claim 8 , wherein the second field includes one bit. 
     
     
         11 . The UE of  claim 8 , wherein:
 the first field is included in a DCI format that schedules a physical downlink shared channel (PDSCH) reception, and   the second field in never included in the DCI format that schedules a PDSCH reception.   
     
     
         12 . The UE of  claim 8 , wherein:
 the cell includes one downlink (DL) carrier for reception,   the cell includes two uplink (UL) carriers for transmission, and   the transceiver is further configured to transmit only on one of the two UL carriers at a given time.   
     
     
         13 . The UE of  claim 8 , wherein:
 the cell includes one downlink (DL) carrier for reception,   the cell includes two uplink (UL) carriers for transmission,   the DL carrier and the first of the two UL carriers are in a first frequency band, and   the second of the two UL carriers is in a second frequency band.   
     
     
         14 . The UE of  claim 13 , wherein the second frequency band is at a lower frequency that the first frequency band. 
     
     
         15 . A base station comprising:
 a transceiver configured to transmit a physical downlink control channel (PDCCH) that provides a downlink control information (DCI) format, wherein:
 the DCI format schedules a PUSCH reception, 
 the DCI format includes a first field indicating a cell, and 
 the DCI format includes a second field indicating a carrier of the cell, wherein the transceiver is further configured to receive the PUSCH on the carrier of the cell. 
   
     
     
         16 . The base station of  claim 15 , wherein:
 the transceiver is further configured to transmit a system information block (SIB), and   the SIB includes configuration information for a first uplink (UL) carrier and for a second UL carrier.   
     
     
         17 . The base station of  claim 15 , wherein the second field includes one bit. 
     
     
         18 . The base station of  claim 15 , wherein:
 the first field is included in a DCI format that schedules a physical downlink shared channel (PDSCH) transmission, and   the second field in never included in the DCI format that schedules a PDSCH transmission.   
     
     
         19 . The base station of  claim 15 , wherein:
 the cell includes one downlink (DL) carrier for transmission,   the cell includes two uplink (UL) carriers for reception,   the DL carrier and the first of the two UL carriers are in a first frequency band, and   the second of the two UL carriers is in a second frequency band.   
     
     
         20 . The base station of  claim 19 , wherein the second frequency band is at a lower frequency that the first frequency band.