Method for reporting channel state information in wireless communication system and device therefor
According to the present specification, a method for reporting channel state information (CSI) in a wireless communication system, which is performed by a UE includes: transmitting UE capability information including second control information indicating the total number of CSI-RS resources which are maximally supported in one CSI process to a base station. Therefore, there is an effect that implementation complexity of the UE can be reduced.
1. A method for reporting, by a user equipment (UE), channel state information (CSI) in a wireless communication system, the method comprising:
transmitting, to a base station, UE capability information including second control information indicating a maximum number of channel state information-reference signal (CSI-RS) resources which are supported in a CSI process;
receiving, from the base station, a CSI process related information including CSI-RS configuration information through a higher layer signaling;
receiving, from the base station, at least one CSI-RS based on the received CSI process related information,
wherein the at least one CSI-RS is transmitted on at least one CSI-RS port;
measuring a channel based on the received at least one CSI-RS; and
reporting, to the base station, a result of the channel measurement.
2. The method of claim 1 , further comprising:
transmitting, to the base station, third control information indicating a total number of CSI-RS ports supported for each CSI-RS resource.
3. The method of claim 1 , wherein the UE capability information further includes first control information indicating a maximum number of CSI-RS ports supported in the CSI process.
4. The method of claim 1 , wherein the UE capability information further includes CSI reporting type information related to a CSI reporting type supported by the UE.
5. The method of claim 4 , wherein the CSI reporting type information includes at least one of a first type representing a non-precoded CSI-RS based CSI reporting operation and a second type representing a beamformed CSI-RS based CSI reporting operation.
6. The method of claim 5 , wherein when the CSI reporting type information is set to the second type, and
wherein the second control information is included in the UE capability information.
7. The method of claim 1 , wherein the second control information is set to be the same as each other or different from each other for each CSI process.
8. The method of claim 1 , wherein the CSI process related information further includes type indication information representing a CSI reporting type to be performed by the UE.
9. The method of claim 1 , wherein the at least one CSI-RS port includes 8, 12, 16, 24, 32 and 64.
10. The method of claim 3 , wherein the first control information includes a plurality of Nmax values including Nmax2, Nmax3, and Nmax4 when a value of the second control information is larger than a specific value, and
wherein each Nmax value is a supported maximum number of CSI-RS ports at a value of a specific second control information.
11. The method of claim 10 , wherein the each Nmax value is 8, 16, 32 or 64.
12. The method of claim 10 , wherein the specific value is ‘1’.
13. The method of claim 1 , wherein the UE capability information includes fourth control information indicating a maximum number of CSI processes supported by the UE.
14. The method of claim 13 , wherein a value of the fourth control information is 1, 3, or 4.
15. The method of claim 1 , wherein the second control information is applied to a specific transmission mode and band combinations.
16. The method of claim 15 , wherein the second control information has a value from 1 to 8.
17. A user equipment (UE) for reporting channel state information (CSI) in a wireless communication system, the UE comprising:
one or more antennas configured to transmit and receive a radio signal; and
a processor configured to:
transmit, to a base station, UE capability information including second control information indicating a maximum number of channel state information-reference signal (CSI-RS) resources which are supported in a CSI process,
receive, from the base station, a CSI process related information including CSI-RS configuration information through a higher layer signaling,
receive, from the base station, at least one CSI-RS based on the received CSI process related information,
wherein the at least one CSI-RS is transmitted on at least one CSI-RS port,
measure a channel based on the received at least one CSI-RS, and
report, to the base station, a result of the channel measurement.
18. The UE of claim 17 , wherein the processor is configured to transmit, to the base station, third control information indicating a total number of CSI-RS ports maximally supported for each CSI-RS resource.
19. The UE of claim 17 , wherein the UE capability information further includes CSI reporting type information related to a CSI reporting type supported by the UE, and
wherein the CSI reporting type information includes at least one of a non-precoded CSI-RS based CSI reporting operation type and a beamformed CSI-RS based CSI reporting operation type.
20. The UE of claim 19 , wherein the processor controls the second control information to be included in the UE capability information when the CSI reporting type information is set to ‘the beamformed CSI-RS based CSI reporting operation type’.