Method and apparatus for reporting channel status information in wireless communication system
The present invention relates to a wireless communication system and, more specifically, to a method and an apparatus for reporting channel status information (CSI). Particularly, the method by which a terminal in the wireless communication system reports the CSI, comprises the steps of: receiving a reference signal from a base station; and reporting, to the base station, the CSI generated by using the reference signal, wherein the CSI includes channel information for a plurality of antenna ports mapped according to a first parameter, and the first parameter is a value related to vertical domain antenna ports indicated through upper layer signaling.
1. A method for reporting channel state information (CSI) by a user equipment (UE) in a wireless communication system, the method comprising:
receiving a channel state information-reference signal (CSI-RS) configuration including a parameter indicating the number of antenna ports per polarization in a plurality of dimensions and an indicator for a MIMO(multiple-input multiple-output) related with elevation beamforming;
configuring a plurality of antenna ports based on the CSI-RS configuration, when the UE is configured for the MIMO related with elevation beamforming; and
reporting the CSI in response to a reference signal received via the number of antenna ports, wherein the CSI is applied a subset of a codebook according to the plurality of antenna ports and the parameter, and
wherein the subset of the codebook is indicated by the indicator for the MIMO related with elevation beamforming.
2. The method according to claim 1 , wherein the number of the plurality of antenna ports is 8 or more.
3. The method according to claim 1 , wherein predefined horizontal domain antenna ports and an antenna port number determined by the parameter are sequentially mapped to the plurality of antenna ports.
4. The method according to claim 1 , wherein the plurality of antenna ports are configured in such a way that an antenna port number is mapped to a horizontal domain antenna port and then an antenna port number is mapped to a vertical domain antenna port.
5. The method according to claim 1 , wherein the plurality of antenna ports are configured in such a way that an antenna port number is completely mapped to a first pole of antenna port and then an antenna port number is mapped to a second pole of antenna port.
6. The method according to claim 5 , wherein the first pole of antenna port and the second pole of antenna port are configured to be orthogonal to each other.
7. A user equipment (UE) for reporting channel state information (CSI) of a wireless communication system, the UE comprising:
a radio frequency unit; and
a processor,
wherein:
the processor is configured to
receive a channel state information-reference signal (CSI-RS) configuration including a parameter indicating the number of antenna ports per polarization in a plurality of dimensions and an indicator for a MIMO (multiple-input multiple-output) related with elevation beamforming,
configure a plurality of antenna ports based on the CSI-RS configuration, when the UE is configured for the MIMO related with elevation beamforming, and
report the CSI in response to a reference signal received via the number of antenna ports, wherein the CSI is applied a subset of a codebook according to the plurality of antenna ports and the parameter, and
wherein the subset of the codebook is indicated by the indicator for the MIMO related with elevation beamforming.