Method and apparatus for transmitting or receiving channel state information in wireless communication system
Disclosed are a method and an apparatus for transmitting or receiving channel state information in a Wireless communication system. A method for transmitting channel state information (CSI) according to an embodiment of the present disclosure may comprise the steps of receiving configuration information related to the CSI; receiving a channel state information reference signal (CSI-RS) through a plurality of CSI-RS ports; and transmitting the CSI for each at least one CSI-RS port group on the basis of the configuration information, Wherein the plurality of CSI-RS ports are grouped into at least one CSI-RS port group, each of the at least one CSI-RS port group includes at least one CSI-RS port, and the CSI includes one or more of a port index, a delay value, and a coefficient for each of one or more specific CSI-RS ports for the each at least one CSI-RS port group.
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 channel state information reference signal (CSI-RS) through a plurality of CSI-RS ports; and
transmitting, by the UE to the base station, the CSI for each of at least one CSI-RS port group based on the configuration information,
wherein the plurality of CSI-RS ports are grouped into the at least one CSI-RS port group,
wherein each of the at least one CSI-RS port group includes at least one CSI-RS port, and
wherein the CSI includes a port index, a delay value, and a coefficient for each of at least one CSI-RS port for each of the at least one CSI-RS port group.
2. The method of claim 1 , wherein:
the configuration information includes information on a number of combinations of at least one of the CSI-RS port index, the delay value, or the coefficient to be reported for each of the at least one CSI-RS port group.
3. The method of claim 1 , wherein:
the configuration information includes information on at least one of a range of delay values for each of the at least one CSI-RS port group or a number of CSI-RS ports included in the at least one CSI-RS port group.
4. The method of claim 1 , wherein:
information on a capability of the UE related to at least one of a range of delay values or a number of CSI-RS ports is transmitted to the base station.
5. The method of claim 1 , wherein:
the CSI-RS is transmitted from the base station based on a number of CSI-RS ports included in the at least one CSI-RS port group and an uplink channel estimation value, through at least one CSI-RS port for which a delay value is pre-compensated.
6. The method of claim 5 , wherein:
the pre-compensated delay value is determined or predefined based on a delay range for each CSI-RS port group including the at least one CSI-RS port.
7. The method of claim 1 , wherein:
each of the at least one CSI-RS port group corresponds to at least one non-zero power (NZP) CSI-RS resource, and
the configuration information includes information for configuring K (K is a natural number) NZP CSI-RS resources including at least one CSI-RS port and an NZP CSI-RS resource set including the K NZP CSI-RS resources.
8. The method of claim 7 , wherein:
the CSI includes at least one of L (K≥L, L is a natural number) NZP CSI-RS resources among the K NZP CSI-RS resources, a port index of at least one of specific CSI-RS port for each of the L NZP CSI-RS resources, and a coefficient or delay value related to at least one of specific CSI-RS port for each of the L NZP CSI-RS resources.
9. The method of claim 7 , wherein:
the configuration information includes information for configuring each of the K NZP CSI-RS resources to have different time domain characteristics, and
the time domain characteristics is one of periodic, semi-persistent, or aperiodic.
10. The method of claim 7 , wherein:
the CSI includes at least one CSI-RS resource indicator (CRI), and
the CSI includes a port index of each of at least one specific CSI-RS port for each of the L NZP CSI-RS resources, at least one of delay values or coefficients associated with each of the at least one specific CSI-RS port for each of the L NZP CSI-RS resources, and CRI corresponding to each of the L NZP CSI-RS resources.
11. The method of claim 7 , wherein:
when a CSI-RS port having an amplitude equal to or greater than a specific threshold exists in a first NZP CSI-RS resource among the K NZP CSI-RS resources, the CSI further includes a CRI corresponding to the first NZP CSI-RS.
12. The method of claim 1 , wherein:
downlink transmission from the base station is performed based on a precoding matrix and a coefficient determined based on a port index of each of the at least one CSI-RS port for each of the at least one CSI-RS port group and the delay value and coefficient of each of the at least one CSI-RS port.
13. The method of claim 1 , wherein:
the coefficient includes at least one of an amplitude value or a phase value.
14. A user equipment (UE) comprising:
at least one transceiver for transmitting and receiving radio signals; and
at least one processor controlling the at least one transceiver,
wherein the at least one processor is configured to:
receive, from a base station through the at least one transceiver, configuration information related to channel state information (CSI);
receive, from the base station through the at least one transceiver, a channel state information reference signal (CSI-RS) through a plurality of CSI-RS ports; and
transmit, to the base station through the at least one transceiver, the CSI for each of at least one CSI-RS port group based on the configuration information,
wherein the plurality of CSI-RS ports are grouped into the at least one CSI-RS port group,
wherein each of the at least one CSI-RS port group includes at least one CSI-RS port, and
wherein the CSI includes a port index, a delay value, and a coefficient for each of at least one CSI-RS port for each of the at least one CSI-RS port group.
15. A base station comprising:
at least one transceiver for transmitting and receiving radio signals; and
at least one processor controlling the at least one transceiver,
wherein the at least one processor is configured to:
transmit, to a user equipment (UE) through the at least one transceiver, configuration information related to channel state information (CSI);
transmit, to the UE through the at least one transceiver, a channel state information reference signal (CSI-RS) through a plurality of CSI-RS ports; and
receive, from the UE through the at least one transceiver, the CSI for each of at least one CSI-RS port group based on the configuration information,
wherein the plurality of CSI-RS ports are grouped into the at least one CSI-RS port group,
wherein each of the at least one CSI-RS port group includes at least one CSI-RS port, and
wherein the CSI includes a port index, a delay value, and a coefficient for each of at least one specific CSI-RS port for each of the at least one CSI-RS port group.