Transmission of scheduling assignments in multiple operating bandwidths
Methods and apparatuses are described for the transmission of Scheduling Assignments (SAs) from a base station to User Equipments (UEs) for data reception in the downlink or data transmission in the uplink of a communication system consisting of multiple Component Carriers (CCs). The SAs are separately coded and transmitted using elementary units (Control Channel Elements or CCEs). Locations of CCEs determine whether an SA is intended for a first CC or for a second CC. Further, the location of CCEs for an SA intended for a first CC is used to determine locations of CCEs for an SA intended for a second CC.
1. A method for transmitting a plurality of scheduling assignments (SA) through a downlink control channel in a wireless communication system supporting carrier aggregation, the method comprising the steps of:
transmitting to a user equipment (UE) a first SA for a first Component Carrier (CC) using a first set of Control Channel Elements (CCEs); and
transmitting to the UE a second SA for a second CC using a second set of CCEs,
wherein a second set of CCEs is positioned away by a predetermined number of CCEs relative to the first set of CCEs, and the predetermined number of CCEs correspond to a value of a CC indicator.
2. The method of claim 1 , wherein the UE is configured with the first CC and the second CC from among multiple CCs.
3. An apparatus for transmitting a plurality of Scheduling Assignments (SA) through a downlink control channel in a wireless communication system supporting carrier aggregation, the apparatus comprising:
a transmitter configured to transmit an SA to a user equipment (UE); and
a controller configured to control operations of transmitting to the UE a first SA for a first Component Carrier (CC) using a first set of control channel element (CCEs), and transmitting to the UE a second SA for a second CC using a second set of CCEs,
wherein a second set of CCEs is positioned away by a predetermined number of CCEs relative to the first set of CCEs, and the predetermined number of CCEs correspond to a value of a CC indicator.
4. The apparatus of claim 3 , wherein the UE is configured with the first CC and the second CC from among multiple CCs.
5. A method for searching a plurality of Scheduling Assignments (SA) through a downlink control channel by a User Equipment (UE) in a wireless communication system supporting carrier aggregation, the method comprising the steps of:
searching a first SA for a first component carrier (CC), the first SA being transmitted from a base station by using a first set of control channel elements (CCEs); and
searching a second SA for a second CC, the second SA being transmitted from the base station by using a second set of CCEs,
wherein a second set of CCEs is positioned away by a predetermined number of CCEs relative to the first set of CCEs, and the predetermined number of CCEs correspond to a value of a CC indicator.
6. The method of claim 5 , wherein the UE is configured with the first CC and the second CC from among multiple CCs.
7. A user equipment (UE) for searching a plurality of scheduling assignments (SA) through a downlink control channel in a wireless communication system supporting carrier aggregation, the comprising:
a receiver configured to receive a signal from a base station; and
a controller configured to control operations of searching a first SA for a first component carrier (CC), the first SA being transmitted from the base station by using a first set of Control Channel Element (CCEs), and searching a second SA for a second CC, the second SA being transmitted from the base station by using a second set of CCEs,
wherein a second set of CCEs is positioned away by a predetermined number of CCEs relative to the first set of CCEs, and the predetermined number of CCEs correspond to a value of a CC indicator.
8. The UE of claim 7 , wherein the UE is configured with the first CC and the second CC from among multiple CCs.