Method and apparatus for transmitting aperiodic channel state information in wireless communication system
A method performed by a base station (BS) is provided for receiving aperiodic channel state information (CSI). The BS transmits a CSI request field which is set to trigger a CSI report to a user equipment (UE), and receives CSI through a physical uplink shared channel (PUSCH) from the UE. The CSI request field has a value among a plurality of candidate values and the plurality of candidate values comprises a first value which triggers an aperiodic CSI report for a first set of reference signals and a second value which triggers an aperiodic CSI report for a second set of reference signals. The first set and the second set of reference signals are configured by a higher layer signal.
1. A method for receiving aperiodic channel state information (CSI), the method performed by a base station (BS) and comprising:
transmitting a CSI request field which is set to trigger a CSI report to a user equipment (UE),
wherein the CSI request field is included in downlink control information (DCI) which is transmitted through a physical downlink control channel (PDCCH); and
receiving CSI through a physical uplink shared channel (PUSCH) from the UE,
wherein the PUSCH is scheduled by the DCI,
wherein the CSI request field has a value among a plurality of candidate values,
wherein the plurality of candidate values include a first value which triggers an aperiodic CSI report for a first set of reference signals and a second value which triggers an aperiodic CSI report for a second set of reference signals, and
wherein the first set of reference signals and the second set of reference signals are configured by a higher layer signal.
2. The method of claim 1 , wherein the CSI request field is composed of a plurality of bits.
3. The method of claim 1 , wherein the higher layer signal is a radio resource control (RRC) message.
4. A base station (BS), comprising:
a radio frequency (RF) unit configured to transmit and receive radio signals; and
a processor coupled to the RF unit,
wherein the processor is configured to:
transmit a channel state information (CSI) request field which is set to trigger a CSI report to a user equipment (UE),
wherein the CSI request field is included in downlink control information (DCI) which is transmitted through a physical downlink control channel (PDCCH), and
receive CSI through a physical uplink shared channel (PUSCH) from the UE,
wherein the PUSCH is scheduled by the DCI,
wherein the CSI request field has a value among a plurality of candidate values,
wherein the plurality of candidate values include a first value which triggers an aperiodic CSI report for a first set of reference signals and a second value which triggers an aperiodic CSI report for a second set of reference signals, and
wherein the first set of reference signals and the second set of reference signals are configured by a higher layer signal.
5. The BS of claim 4 , wherein the CSI request field is composed of a plurality of bits.
6. The BS of claim 4 , wherein the higher layer signal is a radio resource control (RRC) message.
7. A method for transmitting aperiodic channel state information (CSI), the method performed by a user equipment (UE) and comprising:
receiving a CSI request field,
wherein the CSI request field is included in downlink control information (DCI) which is received through a physical downlink control channel (PDCCH);
generating CSI if the CSI request field is set to trigger a CSI report; and
transmitting the CSI through a physical uplink shared channel (PUSCH),
wherein the PUSCH is scheduled by the DCI,
wherein the CSI request field has a value among 4 candidate values,
wherein the 4 candidate values include a first value which triggers an aperiodic CSI report for a first set of reference signals and a second value which triggers an aperiodic CSI report for a second set of reference signals, and
wherein the first set of reference signals and the second set of reference signals are configured by a higher layer signal.
8. The method of claim 7 , wherein the CSI request field is composed of a plurality of bits.
9. The method of claim 7 , wherein the higher layer signal is a radio resource control (RRC) message.
10. A user equipment (UE), comprising:
a radio frequency (RF) unit configured to transmit and receive radio signals; and
a processor coupled to the RF unit,
wherein the processor is configured to:
receive a channel state information (CSI) request field,
wherein the CSI request field is included in downlink control information (DCI) which is received through a physical downlink control channel (PDCCH),
generate CSI if the CSI request field is set to trigger a CSI report, and
transmit the CSI through a physical uplink shared channel (PUSCH),
wherein the PUSCH is scheduled by the DCI,
wherein the CSI request field has a value among 4 candidate values,
wherein the 4 candidate values include a first value which triggers an aperiodic CSI report for a first set of reference signals and a second value which triggers an aperiodic CSI report for a second set of reference signals, and
wherein the first set of reference signals and the second set of reference signals are configured by a higher layer signal.
11. The UE of claim 10 , wherein the CSI request field is composed of a plurality of bits.
12. The UE of claim 10 , wherein the higher layer signal is a radio resource control (RRC) message.