A user equipment of a wireless communication system, comprising: a communication module; and a processor configured to control the communication module, wherein the processor is configured to: receive downlink control information, DCI, through a physical downlink control channel, PDCCH, indicating physical downlink shared channel, PDSCH, scheduling information of each cell in one or more cells, wherein a code block group, CBG,-based transmission is configured in at least one cell among the one or more cells, wherein the DCI includes a counter downlink assignment index, DAI, and a total DAI individually applied according to a transmission scheme, the counter DAI indicating an accumulated number of PDSCHs scheduled up to the current cell and the total-DAI indicating a total number of PDSCHs scheduled for entire cells, identify the transmission scheme in each cell based on a DCI format of the DCI, wherein the transmission scheme is either a transport block, TB,-based transmission or the CBG-based transmission, receive a PDSCH of each cell in the one or more cells based on the scheduling information of the PDCCH, generate a hybrid automatic repeat request acknowledgment, HARQ-ACK, bit sequence for the one or more cells based on the identified transmission scheme of each cell in response to receiving the PDSCH of each cell, the HARQ-ACK bit sequence including a first HARQ-ACK bit sequence for the TB-based transmission and a second HARQ-ACK bit sequence for the CBG-based transmission, wherein, the first HARQ-ACK bit sequence for the TB-based transmission and the second HARQ-ACK bit sequence for the CBG-based transmission are separately generated by individually applying the counter DAI and the total DAI according to the transmission scheme thereto, and transmit the generated HARQ-ACK bit sequence. a communication module; and a processor configured to control the communication module, wherein the processor is configured to: receive downlink control information, DCI, through a physical downlink control channel, PDCCH, indicating physical downlink shared channel, PDSCH, scheduling information of each cell in one or more cells, wherein a code block group, CBG,-based transmission is configured in at least one cell among the one or more cells, wherein the DCI includes a counter downlink assignment index, DAI, and a total DAI individually applied according to a transmission scheme, the counter DAI indicating an accumulated number of PDSCHs scheduled up to the current cell and the total-DAI indicating a total number of PDSCHs scheduled for entire cells, identify the transmission scheme in each cell based on a DCI format of the DCI, wherein the transmission scheme is either a transport block, TB,-based transmission or the CBG-based transmission, receive a PDSCH of each cell in the one or more cells based on the scheduling information of the PDCCH, generate a hybrid automatic repeat request acknowledgment, HARQ-ACK, bit sequence for the one or more cells based on the identified transmission scheme of each cell in response to receiving the PDSCH of each cell, the HARQ-ACK bit sequence including a first HARQ-ACK bit sequence for the TB-based transmission and a second HARQ-ACK bit sequence for the CBG-based transmission, wherein, the first HARQ-ACK bit sequence for the TB-based transmission and the second HARQ-ACK bit sequence for the CBG-based transmission are separately generated by individually applying the counter DAI and the total DAI according to the transmission scheme thereto, and transmit the generated HARQ-ACK bit sequence. receive downlink control information, DCI, through a physical downlink control channel, PDCCH, indicating physical downlink shared channel, PDSCH, scheduling information of each cell in one or more cells, wherein a code block group, CBG,-based transmission is configured in at least one cell among the one or more cells, wherein the DCI includes a counter downlink assignment index, DAI, and a total DAI individually applied according to a transmission scheme, the counter DAI indicating an accumulated number of PDSCHs scheduled up to the current cell and the total-DAI indicating a total number of PDSCHs scheduled for entire cells, identify the transmission scheme in each cell based on a DCI format of the DCI, wherein the transmission scheme is either a transport block, TB,-based transmission or the CBG-based transmission, receive a PDSCH of each cell in the one or more cells based on the scheduling information of the PDCCH, generate a hybrid automatic repeat request acknowledgment, HARQ-ACK, bit sequence for the one or more cells based on the identified transmission scheme of each cell in response to receiving the PDSCH of each cell, the HARQ-ACK bit sequence including a first HARQ-ACK bit sequence for the TB-based transmission and a second HARQ-ACK bit sequence for the CBG-based transmission, wherein, the first HARQ-ACK bit sequence for the TB-based transmission and the second HARQ-ACK bit sequence for the CBG-based transmission are separately generated by individually applying the counter DAI and the total DAI according to the transmission scheme thereto, and transmit the generated HARQ-ACK bit sequence.