Method for transmitting control information and apparatus for same
The present invention relates to a wireless communication system. More particularly, the present invention relates to a method and an apparatus for transmitting uplink control information in the wireless communication system, which supports carrier aggregation and operates by a TDD, and comprises the steps of: deciding HARQ-ACK bit numbers for each cell from a plurality of cells; composing a HARQ-ACK payload comprising HARQ-ACK bit(s) for each of the plurality of cells; and transmitting the HARQ-ACK payload from a subframe n through a PUSCH.
1. A method for transmitting uplink control information in a wireless communication system supporting carrier aggregation and operating in a time division duplex (TDD), the method comprising:
determining the number of per-cell hybrid automatic repeat request-acknowledgement (HARQ-ACK) bits for each cell included in a plurality of cells;
configuring a HARQ-ACK payload including a plurality of per-cell HARQ-ACK bit(s); and
transmitting the HARQ-ACK payload in a subframe n through a physical uplink shared channel (PUSCH),
wherein, when the plurality of cells do not include a cell to which transmission timing according to a specific uplink-downlink (UL-DL) configuration is applied, the number of per-cell HARQ-ACK bits for each cell is determined using a value of min(W, Mc),
wherein, when the plurality of cells include one or more cells to which transmission timing according to the specific UL-DL configuration is applied, the number of per-cell HARQ-ACK bits for each cell is determined using a value of min(W+4┌(U max −W)/4┐, Mc), and
wherein W denotes a value indicated by a 2-bit uplink downlink assignment index (UL DAI) field corresponding to the PUSCH, Mc denotes the number of downlink subframes corresponding to the uplink subframe n for each cell, U max denotes a maximum value from among the numbers of downlink signals requiring HARQ-ACK responses per cell, and ┌ ┐ denotes a ceiling function.
2. The method according to claim 1 , wherein the specific UL-DL configuration corresponds to UL-DL configuration #5,
wherein the UL-DL configuration #5 has the following radio frame configuration:
Subframe number
0
1
2
3
4
5
6
7
8
9
D
S
U
D
D
D
D
D
D
D,
and
wherein D denotes a downlink subframe, U denotes an uplink subframe and S denotes a special subframe.
3. The method according to claim 1 , wherein the plurality of per-cell HARQ-ACK bit(s) are concatenated in an ascending order of cell index in the HARQ-ACK payload.
4. The method according to claim 1 , wherein the downlink signals requiring HARQ-ACK responses include a physical downlink shared channel (PDSCH) signal and a physical downlink control channel (PDCCH) signal indicating semi-persistent scheduling (SPS) release.
5. The method according to claim 1 , wherein the method is performed by a communication device configured to transmit HARQ-ACK using physical uplink control channel (PUCCH) format 3 in Long Term Evolution-Advanced protocol.
6. A communication device configured to transmit uplink control information in a wireless communication system supporting carrier aggregation and operating in a time division duplex (TDD), the communication device comprising:
a radio frequency (RF) unit; and
a processor,
wherein the processor is configured to determine the number of per-cell hybrid automatic repeat request acknowledgement (HARQ-ACK) bits for each cell included in a plurality of cells, to configure a HARQ-ACK payload including a plurality of per-cell HARQ-ACK bit(s), and to transmit the HARQ-ACK payload in a subframe n through a physical uplink shared channel (PUSCH),
wherein, when the plurality of cells do not include a cell to which transmission timing according to a specific uplink-downlink (UL-DL) configuration is applied, the number of HARQ-ACK bits for each cell is determined using a value of min(W, Mc),
wherein, when the plurality of cells include one or more cells to which transmission timing according to the specific UL-DL configuration is applied, the number of per-cell HARQ-ACK bits for each cell is determined using a value of min(W+4┌(U max −W)/4┐, Mc), and
wherein W denotes a value indicated by a 2-bit uplink downlink assignment index (UL DAI) field corresponding to the PUSCH, Mc denotes the number of downlink subframes corresponding to the uplink subframe n for each cell, U max denotes a maximum value from among the numbers of downlink signals requiring HARQ-ACK responses per cell, and ┌┐ denotes a ceiling function.
7. The communication device according to claim 6 , wherein the specific UL-DL configuration corresponds to UL-DL configuration #5,
wherein the UL-DL configuration #5 has the following radio frame configuration:
Subframe number
0
1
2
3
4
5
6
7
8
9
D
S
U
D
D
D
D
D
D
D,
and
wherein D denotes a downlink subframe, U denotes an uplink subframe and S denotes a special subframe.
8. The communication device according to claim 6 , wherein the plurality of per-cell HARQ-ACK bit(s) are concatenated in an ascending order of cell index in the HARQ-ACK payload.
9. The communication device according to claim 6 , wherein the downlink signals requiring HARQ-ACK responses include a physical downlink shared channel (PDSCH) signal and a physical downlink control channel (PDCCH) signal indicating semi-persistent scheduling (SPS) release.
10. The communication device according to claim 6 , wherein the communication device is configured to transmit HARQ-ACK using physical uplink control channel (PUCCH) format 3 in Long Term Evolution-Advanced protocol.