Method and device for transmitting and receiving channel state information in wireless communication system

1 . A method comprising:

receiving, by a user equipment (UE), from a base station, configuration information related to channel state information (CSI);

receiving, by the UE, from the base station, a CSI-reference signal (CSI-RS) on one or more CSI resources; and

transmitting, by the UE, to the base station, the CSI based on the configuration information,

wherein the CSI includes a precoding matrix indicator (PMI) corresponding to indices of a codebook for indicating a precoding matrix,

wherein the PMI includes one or more amplitude coefficient indicators for indicating an amplitude coefficient and one or more phase coefficient indicators for indicating a phase coefficient, and

wherein whether a bitmap for identifying which coefficients are reported by the one or more amplitude coefficient indicators and the one or more phase coefficient indicators is reported in the PMI is determined based on a specific value for a number of non-zero amplitude coefficients and phase coefficients summed across all layers.

2 . The method of claim 1 , wherein the configuration information includes information for determining the specific value.

3 . The method of claim 1 , wherein the codebook is a codebook based on linear combining.

4 . A user equipment (UE) comprising:

at least one transceiver for transmitting and receiving a wireless signal; and

at least one processor for controlling the at least one transceiver,

wherein the at least one processor configured to:

receive, from a base station, configuration information related to channel state information (CSI);

receive, from the base station, a CSI-reference signal (CSI-RS) on one or more CSI resources; and

transmit, to the base station, the CSI based on the configuration information,

wherein the CSI includes a precoding matrix indicator (PMI) corresponding to indices of a codebook for indicating a precoding matrix,

wherein the PMI includes one or more amplitude coefficient indicators for indicating an amplitude coefficient and one or more phase coefficient indicators for indicating a phase coefficient, and

wherein whether a bitmap for identifying which coefficients are reported by the one or more amplitude coefficient indicators and the one or more phase coefficient indicators is reported in the PMI is determined based on a specific value for a number of non-zero amplitude coefficients and phase coefficients summed across all layers.

5 . A base station comprising:

at least one transceiver for transmitting and receiving a wireless signal; and

at least one processor for controlling the at least one transceiver,

wherein the at least one processor configured to:

transmit, to a user equipment (UE), configuration information related to channel state information (CSI);

transmit, to the UE, a CSI-reference signal (CSI-RS) on one or more CSI resources; and

receive, from the UE, the CSI based on the configuration information, wherein the CSI includes a precoding matrix indicator (PMI) corresponding to indices of a codebook for indicating a precoding matrix,

wherein the PMI includes one or more amplitude coefficient indicators for indicating an amplitude coefficient and one or more phase coefficient indicators for indicating a phase coefficient, and

wherein whether a bitmap for identifying which coefficients are reported by the one or more amplitude coefficient indicators and the one or more phase coefficient indicators is reported in the PMI is determined based on a specific value for a number of non-zero amplitude coefficients and phase coefficients summed across all layers.

6 . The base station of claim 5 , wherein the configuration information includes information for determining the specific value.

7 . The base station of claim 5 , wherein the codebook is a codebook based on linear combining.