Method for operating terminal in carrier aggregation system, and apparatus using said method
A method for operating a terminal in a carrier aggregation system and a corresponding apparatus. In the method, downlink control information (DCI) including a downlink assignment index (DAI) can be received via an enhanced physical downlink control channel (E-PDCCH). The DCI received via the E-PDCCH includes an additional field which does not exist in the DCI received via a physical downlink control channel (PDCCH). If the DAI value is larger than 1, the additional field is used in selecting one of a plurality of PUCCH resources set by the upper layer, and the selected one resource is used in transmitting ACK/NACK.
1. A method of operating a terminal in a carrier aggregation system, the method comprising:
receiving downlink control information (DCI) including a downlink assignment index (DAI) through an enhanced physical downlink control channel (E-PDCCH) of a first subframe;
receiving data scheduled by the DCI through a physical downlink shared channel (PDSCH) of the first subframe;
transmitting an acknowledgement (ACK)/not-acknowledgement (NACK) for the data through a physical uplink control channel (PUCCH) in a second subframe,
wherein the DCI received in the E-PDCCH includes an additional field which is not present in DCI received in a physical downlink control channel (PDCCH), and
wherein if the DAI value is greater than 1, the additional field is used to select a single resource among a plurality of PUCCH resources configured by a higher layer, and the single resource is used to transmit the ACK/NACK.
2. The method of claim 1 , wherein the DCI received in the E-PDCCH includes a transmission power control (TPC) field.
3. The method of claim 2 , wherein if the DAI value is greater than 1, the TPC field of the DCI received in the E-PDCCH is used to control uplink transmission power.
4. The method of claim 1 , wherein if the DCI received in the E-PDCCH is received in a primary cell and schedules a PDSCH of a secondary cell and if a PUCCH format 3 is configured for ACK/NACK feedback of the terminal, an additional field included in the DCI received in the E-PDCCH is set to a value of 0.
5. The method of claim 4 , wherein the PUCCH format 3 is a PUCCH format in which a plurality of modulation symbols are transmitted through time-domain spreading by using an orthogonal sequence.
6. The method of claim 1 , wherein if the DAI value of the DCI received in the PDCCH is greater than 1, a TPC field included in the DCI received in the PDCCH is used to select one resource used for ACK/NACK transmission among a plurality of PUCCH resources configured by a higher layer.
7. A terminal operating in a carrier aggregation system, the terminal comprising:
a transceiver for transmitting and receiving a radio signal; and
a processor operatively coupled to the transceiver,
wherein the processor is configured to:
receive downlink control information (DCI) including a downlink assignment index (DAI) through an enhanced physical downlink control channel (E-PDCCH) of a first subframe;
receive data scheduled by the DCI through a physical downlink shared channel (PDSCH) of the first subframe;
transmit an acknowledgement (ACK)/not-acknowledgement (NACK) for the data through a physical uplink control channel (PUCCH) in a second subframe,
wherein the DCI received in the E-PDCCH includes an additional field which is not present in DCI received in a physical downlink control channel (PDCCH), and
wherein if the DAI value is greater than 1, the additional field is used to select a single resource among a plurality of PUCCH resources configured by a higher layer, and the single resource is used to transmit the ACK/NACK.
8. The terminal of claim 7 , wherein the DCI received in the E-PDCCH includes a transmission power control (TPC) field.
9. The terminal of claim 8 , wherein if the DAI value is greater than 1, the TPC field of the DCI received in the E-PDCCH is used to control uplink transmission power.
10. The terminal of claim 7 , wherein if the DCI received in the E-PDCCH is received in a primary cell and schedules a PDSCH of a secondary cell and if a PUCCH format 3 is configured for ACK/NACK feedback of the terminal, an additional field included in the DCI received in the E-PDCCH is set to a value of 0.
11. The terminal of claim 10 , wherein the PUCCH format 3 is a PUCCH format in which a plurality of modulation symbols are transmitted through time-domain spreading by using an orthogonal sequence.
12. The terminal of claim 7 , wherein if the DAI value of the DCI received in the PDCCH is greater than 1, a TPC field included in the DCI received in the PDCCH is used to select one resource used for ACK/NACK transmission among a plurality of PUCCH resources configured by a higher layer.