Efficient control information transmission method and apparatus for supporting multiple antenna transmission technique
The present invention relates to a wireless communication system and provides an efficient control information transmission method and apparatus for supporting a multiple antenna transmission technique. A method is provided for transmitting downlink hybrid automatic repeat request (HARQ) information related to an uplink multiple codeword transmission and includes receiving the uplink multiple codeword transmission, generating HARQ information related to each of the multiple codewords based on a result of decoding each of the multiple codewords, modulating the HARQ information, and transmitting the modulated HARQ information via one or more physical HARQ indicator channels (PHICHs).
1. A method of transmitting downlink control information (DCI) for scheduling one or more uplink codewords (CWs) by a base station (BS) in a wireless communication system supporting uplink multiple-input multiple-output (UL MIMO), the method comprising:
generating, by the BS, DCI including modulation and coding scheme (MCS) information and new data indicator (NDI) information for each of uplink CWs as uplink scheduling information; and
transmitting, by the BS to a user equipment (UE), the DCI through a physical downlink control channel (PDCCH),
wherein the DCI further includes physical uplink shared channel (PUSCH) resource block allocation information, a transmit power control (TPC) command for a scheduled PUSCH, cyclic shift information for a demodulation reference signal (DMRS), channel state information (CSI) request and precoding information,
wherein the BS determines whether or not to toggle the NDI information for each of the uplink CWs for scheduling uplink retransmission of each of the uplink CWs,
wherein when a number of transmission antennas for UL MIMO is 2, the precoding information is configured to 3 bits indicating a codebook index from one of a rank 1-codebook or a rank 2-codebook, and
wherein when the number of transmission antennas for UL MIMO is 4, the precoding information is configured to 6 bits indicating a codebook index from one of the rank 1-codebook, the rank 2-codebook, a rank 3-codebook or a rank 4-codebook.
2. The method according to claim 1 , wherein the DCI further includes an uplink index and a downlink allocation index for time division duplexing (TDD).
3. The method according to claim 2 ,
wherein the NDI information includes first NDI information for a first uplink CW and second NDI information for a second uplink CW, and
wherein the BS does not toggle the first NDI information if the first uplink CW was not received correctly, and the BS does not toggle the second NDI information if the second uplink CW was not received correctly.
4. The method according to claim 3 ,
wherein the first uplink CW is retransmitted by the UE when the first NDI information is not toggled, and the second uplink CW is retransmitted by the UE when the second NDI information is not toggled.
5. The method according to claim 4 , further comprising:
transmitting a physical hybrid automatic repeat request (HARQ) indication channel (PHICH) indicating an acknowledgement (ACK) or a negative acknowledgement (NACK),
wherein the uplink retransmission of each of the uplink CWs is performed based only on the DCI regardless of the PHICH.
6. The method according to claim 5 ,
wherein each of the first NDI information and the second NDI information corresponds to 1-bit, and
wherein each of the first NDI information and the second NDI information is either ‘0’ or ‘1’.
7. A method of receiving downlink control information (DCI) for scheduling one or more uplink codewords (CWs) by a user equipment (UE) in a wireless communication system supporting uplink multiple-input multiple-output (UL MIMO), the method comprising:
receiving, by the UE from a base station (BS) through a physical downlink control channel (PDCCH), DCI including modulation and coding scheme (MCS) information and new data indicator (NDI) information for each of uplink CWs as uplink scheduling information; and
determining, by the UE, whether or not to retransmit each of the uplink CWs based on whether or not the NDI information for each of the uplink CWs is toggled,
wherein the DCI further includes physical uplink shared channel (PUSCH) resource block allocation information, a transmit power control (TPC) command for a scheduled PUSCH, cyclic shift information for a demodulation reference signal (DMRS), channel state information (CSI) request and precoding information,
wherein when a number of transmission antennas for UL MIMO is 2, the precoding information is configured to 3 bits indicating a codebook index from one of a rank 1-codebook or a rank 2-codebook, and
wherein when the number of transmission antennas for UL MIMO is 4, the precoding information is configured to 6 bits indicating a codebook index from one of the rank 1-codebook, the rank 2-codebook, a rank 3-codebook or a rank 4-codebook.
8. The method according to claim 7 , wherein the DCI further includes an uplink index and a downlink allocation index for time division duplexing (TDD).
9. The method according to claim 8 ,
wherein the NDI information includes first NDI information for a first uplink CW and second NDI information for a second uplink CW, and
wherein the first uplink CW is retransmitted by the UE when the first NDI information is not toggled, and the second uplink CW is retransmitted by the UE when the second NDI information is not toggled.
10. The method according to claim 9 ,
wherein uplink retransmission of each of the uplink CWs is performed based only on the DCI regardless of a physical hybrid automatic repeat request (HARQ) indication channel (PHICH) indicating an acknowledgement (ACK) or a negative acknowledgement (NACK).
11. A base station (BS) transmitting downlink control information (DCI) for scheduling one or more uplink codewords (CWs) in a wireless communication system supporting uplink multiple-input multiple-output (UL MIMO), the BS comprising:
a processor to generate DCI including modulation and coding scheme (MCS) information and new data indicator (NDI) information for each of uplink CWs as uplink scheduling information; and
a transmitter to transmit to a user equipment (UE) the DCI through a physical downlink control channel (PDCCH) under control of the processor,
wherein the DCI further includes physical uplink shared channel (PUSCH) resource block allocation information, a transmit power control (TPC) command for a scheduled PUSCH, cyclic shift information for a demodulation reference signal (DMRS), channel state information (CSI) request and precoding information,
wherein the processor determines whether or not to toggle the NDI information for each of the uplink CWs for scheduling uplink retransmission of each of the uplink CWs,
wherein when a number of transmission antennas for UL MIMO is 2, the precoding information is configured to 3 bits indicating a codebook index from one of a rank 1-codebook or a rank 2-codebook, and
wherein when the number of transmission antennas for UL MIMO is 4, the precoding information is configured to 6 bits indicating a codebook index from one of the rank 1-codebook, the rank 2-codebook, a rank 3-codebook or a rank 4-codebook.
12. The BS according to claim 11 , wherein the DCI further includes an uplink index and a downlink allocation index for time division duplexing (TDD).
13. The BS according to claim 12 ,
wherein the NDI information includes first NDI information for a first uplink CW and second NDI information for a second uplink CW, and
wherein the processor does not toggle the first NDI information if the first uplink CW was not received correctly, and the processor does not toggle the second NDI information if the second uplink CW was not received correctly.
14. The BS according to claim 13 ,
wherein the first uplink CW is retransmitted by the UE when the first NDI information is not toggled, and the second uplink CW is retransmitted by the UE when the second NDI information is not toggled.
15. The BS according to claim 14 ,
wherein the transmitter transmits a physical hybrid automatic repeat request (HARQ) indication channel (PHICH) indicating an acknowledgement (ACK) or a negative acknowledgement (NACK), under control of the processor, and
wherein the uplink retransmission of each of the uplink CWs is performed based only on the DCI regardless of the PHICH.
16. The BS according to claim 15 ,
wherein each of the first NDI information and the second NDI information corresponds to 1-bit, and
wherein each of the first NDI information and the second NDI information is either ‘0’ or ‘1’.
17. A user equipment (UE) receiving downlink control information (DCI) for scheduling one or more uplink codewords (CWs) in a wireless communication system supporting uplink multiple-input multiple-output (UL MIMO), the UE comprising:
a receiver; and
a processor to control the receiver to receive, from a base station (BS) through a physical downlink control channel (PDCCH), DCI including modulation and coding scheme (MCS) information and new data indicator (NDI) information for each of uplink CWs as uplink scheduling information, and determine whether or not to retransmit each of the uplink CWs based on whether or not the NDI information for each of the uplink CWs is toggled,
wherein the DCI further includes physical uplink shared channel (PUSCH) resource block allocation information, a transmit power control (TPC) command for a scheduled PUSCH, cyclic shift information for a demodulation reference signal (DMRS), channel state information (CSI) request and precoding information,
wherein when a number of transmission antennas for UL MIMO is 2, the precoding information is configured to 3 bits indicating a codebook index from one of a rank 1-codebook or a rank 2-codebook, and
wherein when the number of transmission antennas for UL MIMO is 4, the precoding information is configured to 6 bits indicating a codebook index from one of the rank 1-codebook, the rank 2-codebook, a rank 3-codebook or a rank 4-codebook.
18. The UE according to claim 17 , wherein the DCI further includes an uplink index and a downlink allocation index for time division duplexing (TDD).
19. The UE according to claim 18 ,
wherein the NDI information includes first NDI information for a first uplink CW and second NDI information for a second uplink CW, and
wherein the first uplink CW is retransmitted by the UE when the first NDI information is not toggled, and the second uplink CW is retransmitted by the UE when the second NDI information is not toggled.
20. The UE according to claim 19 ,
wherein uplink retransmission of each of the uplink CWs is performed based only on the DCI regardless of a physical hybrid automatic repeat request (HARQ) indication channel (PHICH) indicating an acknowledgement (ACK) or a negative acknowledgement (NACK).