CROSS-REFERENCE TO RELATED APPLICATIONS

This application is the National Stage filing under 35 U.S.C. 371 of International Application No. PCT/KR2019/005434, filed on May 7, 2019, which claims the benefit of earlier filing date and right of priority to Korean Application No. 10-2018-0051580, filed on May 4, 2018, the contents of which are all hereby incorporated by reference herein in their entirety.

TECHNICAL FIELD

The present disclosure relates to a wireless communication system, and more particularly to a method for reporting channel state information and a device supporting the same.

BACKGROUND ART

Mobile communication systems have been generally developed to provide voice services while guaranteeing user mobility. Such mobile communication systems have gradually expanded their coverage from voice services through data services up to high-speed data services. However, as current mobile communication systems suffer resource shortages and users demand even higher-speed services, development of more advanced mobile communication systems is needed.

The requirements of the next-generation mobile communication system may include supporting huge data traffic, a remarkable increase in the transfer rate of each user, the accommodation of a significantly increased number of connection devices, very low end-to-end latency, and high energy efficiency. To this end, various techniques, such as small cell enhancement, dual connectivity, massive multiple input multiple output (MIMO), in-band full duplex, non-orthogonal multiple access (NOMA), supporting super-wide band, and device networking, have been researched.

DISCLOSURE

Technical Problem

An object of the present disclosure is to provide a method for reporting channel state information (CSI).

Another object of the present disclosure is to provide a method for distributing and reporting CSI on a time domain.

Another object of the present disclosure is to provide a method for distributing and reporting CSI on a frequency domain.

The technical problems of the present disclosure are not limited to the aforementioned technical problems, and other technical problems which are not mentioned above will be apparently appreciated by a person having ordinary skill in the art from the following description.

Technical Solution

The present disclosure provides a method for reporting channel state information (CSI) in a wireless communication system.

More specifically, the method performed by a user equipment (UE) comprises receiving, from a base station, configuration information related to the channel state information, wherein the configuration information includes a number of a plurality of subbands allocated to the UE; measuring parameter values related to a channel state of one or more subbands of the plurality of subbands based on the configuration information; and reporting, to the base station, channel state information of the one or more subbands including the measured parameter values, wherein a number of the one or more subbands is determined based on a value of a rank indicator (RI).

The number of the one or more subbands is determined by dividing the number of the plurality of subbands by the RI value.

Reporting the channel state information of the one or more subbands is performed at a specific subband interval based on the number of the one or more subbands.

Each of the one or more subbands is comprised of a combination of two or more subbands of the plurality of subbands based on the RI value.

The configuration information includes information for sizes of the plurality of subbands. When the RI value is equal to or greater than a specific criterion, the sizes of the plurality of subbands are determined by a pre-configured value regardless of the configuration information.

The configuration information includes a plurality of candidate values for sizes of the plurality of subbands. When the RI value is equal to or greater than a specific criterion, the sizes of the plurality of subbands are determined by a largest value of the plurality of candidate values.

Other subbands, except the one or more subbands for measuring the parameter values related to the channel state, among the plurality of subbands are dropped.

In another aspect, there is provided a user equipment (UE) reporting channel state information (CSI) in a wireless communication system, the UE comprising a radio frequency (RF) module configured to transmit and receive a radio signal; and a processor functionally connected to the RF module, wherein the processor is configured to receive, from a base station, configuration information related to the channel state information, wherein the configuration information includes a number of a plurality of subbands allocated to the UE; measure parameter values related to a channel state of one or more subbands of the plurality of subbands based on the configuration information; and report, to the base station, channel state information of the one or more subbands including the measured parameter values, wherein a number of the one or more subbands is determined based on a value of a rank indicator (RI).

The number of the one or more subbands is determined by dividing the number of the plurality of subbands by the RI value.

The reporting of the channel state information of the one or more subbands is performed at a specific subband interval based on the number of the one or more subbands.

Each of the one or more subbands is comprised of a combination of two or more subbands of the plurality of subbands based on the RI value.

The configuration information includes information for sizes of the plurality of subbands. When the RI value is equal to or greater than a specific criterion, the sizes of the plurality of subbands are determined by a pre-configured value regardless of the configuration information.

The configuration information includes a plurality of candidate values for sizes of the plurality of subbands. When the RI value is equal to or greater than a specific criterion, the sizes of the plurality of subbands are determined by a largest value of the plurality of candidate values.

Other subbands, except the one or more subbands for measuring the parameter values related to the channel state, among the plurality of subbands are dropped.

In another aspect, there is provided a method for receiving channel state information (CSI) in a wireless communication system, the method performed by a base station comprising transmitting, to a user equipment (UE), configuration information related to the channel state information, wherein the configuration information includes a number of a plurality of subbands allocated to the UE; and receiving, from the UE, channel state information of one or more subbands of the plurality of subbands including parameter values related to a channel state of the one or more subbands of the plurality of subbands measured based on the configuration information, wherein a number of the one or more subbands is determined based on a value of a rank indicator (RI).

Advantageous Effects

The present disclosure has an effect of efficiently reporting channel state information (CSI) by proving a method for reporting a channel state information payload exceeding resources configured to a UE.

The present disclosure also has an effect of efficiently reporting CSI by providing a method for distributing and reporting CSI on a time domain.

The present disclosure also has an effect of efficiently reporting CSI by providing a method for distributing and reporting CSI on a frequency domain.

Advantages which can be obtained in the present disclosure are not limited to the aforementioned effects and other unmentioned advantages will be clearly understood by those skilled in the art from the following description.

