Method and device for reporting channel state information in wireless communication system

A method for receiving channel state information (CSI) by a base station (BS) in a wireless communication system, the method comprising:

• transmitting a reference signal to a user equipment (UE);
• and
• receiving the CSI generated using the reference signal by the UE from the UE,
• wherein the CSI comprises:
• one or more first domain precoding matrix indicators (PMIs) indicating a first precoding matrix for a first domain of a 2D antenna structure;
• and
• one or more second domain PMIs indicating a second precoding matrix for a second domain of the 2D antenna structure,
• wherein the one or more first domain PMIs have a reporting cycle shorter than a reporting cycle of the one or more second domain PMIs,
• wherein the second precoding matrix is indicated by a combination of a second domain PMI_1 and a second domain PMI_2, and
• wherein the second domain PMI_2 has a reporting cycle shorter than a reporting cycle of the second domain PMI_1.

A user equipment (UE) for reporting channel state information (CSI) in a wireless communication system, the UE comprising:

• a transmitter;
• a receiver;
• and
• a processor,
• wherein the processor is configured to:
• control the receiver to receive a reference signal from a base station (BS), and
• control the transmitter to report the CSI generated using the reference signal to the BS,
• wherein the CSI comprises:
• one or more first domain precoding matrix indicators (PMIs) indicating a first precoding matrix for a first domain of a 2D antenna structure;
• and
• one or more second domain PMIs indicating a second precoding matrix for a second domain of the 2D antenna structure,
• wherein the one or more first domain PMIs have a reporting cycle shorter than a reporting cycle of the one or more second domain PMIs,
• wherein the second precoding matrix is indicated by a combination of a second domain PMI_1 and a second domain PMI_2, and
• wherein the second domain PMI_2 has a reporting cycle shorter than a reporting cycle of the second domain PMI_1.

A base station (BS) for receiving channel state information (CSI) in a wireless communication system, the BS comprising:

• a transmitter;
• a receiver;
• and
• a processor,
• wherein the processor is configured to
• control the transmitter to transmit a reference signal to a user equipment (UE), and
• control the receiver to receive the CSI generated using the reference signal by the UE from the UE,
• wherein the CSI comprises:
• one or more first domain precoding matrix indicators (PMIs) indicating a first precoding matrix for a first domain of a 2D antenna structure;
• and
• one or more second domain PMIs indicating a second precoding matrix for a second domain of the 2D antenna structure,
• wherein the one or more first domain PMIs have a reporting cycle shorter than a reporting cycle of the one or more second domain PMIs,
• wherein the second precoding matrix is indicated by a combination of a second domain PMI_1 and a second domain PMI_2, and
• wherein the second domain PMI_2 has a reporting cycle shorter than a reporting cycle of the second domain PMI_1.