Method for signaling control information, and apparatus therefor

A User Equipment (UE) for transmitting Uplink Control Information (UCI) in a wireless communication system, the UE comprising:

• a Radio Frequency (RF) unit;
• and
• a processor,
• wherein the processor is configured to:
• configure plural cells to simultaneously connect to a first base station (BS) and a second BS,
• wherein a first cell group of the plural cells is managed by the first base station and includes a Primary Cell (PCell),
• wherein a second cell group of the plural cells is managed by the second base station and includes one or more Secondary Cells (SCells) and no PCell, and
• wherein the first BS and the second BS are connected by a backhaul link,
• while maintaining a simultaneous connection to the first and second BSs:
• receive one or more data from the second BS in the second cell group, and
• receive one or more data from the first BS in the first cell group, and
• transmit, to the second BS, Hybrid Automatic Repeat reQuest (HARQ)-ACKnowledgement (ACK) information for the one or more data from the second BS on a Physical Uplink Control Channel (PUCCH) in the second group, and
• transmit, to the first BS, HARQ ACK information for the one or more data from the first BS on a PUCCH in the first group.