Beam failure reporting method of terminal in wireless communication system, and terminal and base station supporting same
Disclosed are: a method for a terminal, in a wireless communication system comprising the terminal and a base station including a plurality of cells, to report a beam failure of at least one cell among a plurality of cells set to the terminal; and a terminal and a base station supporting same. According to one applicable embodiment, the terminal can report beam failure information to the base station more efficiently, on the basis of a specific CSI trigger state called/directed from the base station and the at least one cell in which beam failure has occurred, and in response, the base station can recognize, with low signaling overhead, the beam failure of the at least one cell.
1. A method for reporting a beam failure (BF) by a terminal configured with a plurality of cells in a wireless communication system, the method comprising:
receiving, from a base station, configuration information for a plurality of trigger states related to aperiodic channel state information (CSI) reporting; and
based on (i) a control signal related to one trigger state among the plurality of trigger states, and (ii) detection of occurrence of the BF in at least one of the plurality of cells, transmitting, to the base station, BF information based on beam information related to at least one second cell in which the BF has occurred among one or more first cells related to the one trigger state,
wherein the BF information includes (i) identification information about the at least one second cell in which the BF has occurred and (ii) new beam information related to each of the at least one second cell in which the BF has occurred, and
wherein the identification information about the at least one second cell in which the BF has occurred has a bit size determined based on a number of the plurality of cells configured for the terminal.
2. The method of claim 1 ,
wherein the BF information is determined based only on the beam information related to the at least one second cell in which the BF has occurred among the one or more first cells related to the one trigger state.
3. The method of claim 1 ,
wherein the configuration information is received through higher layer signaling.
4. The method of claim 1 ,
wherein the one trigger state is configured to be related to BF reporting.
5. The method of claim 1 ,
wherein the control signal includes downlink control information (DCI).
6. The method of claim 1 , wherein the new beam information comprises
identification information about a new beam related to each of the at least one second cell in which the BF has occurred or a reference signal related to the new beam; and
quality information about the new beam related to each of the at least one second cell or the reference signal related to the new beam,
wherein the new beam related to each of the at least one second cell comprises a beam preferred by the terminal or having a best quality among candidate beams configured for each of the at least one second cell.
7. The method of claim 1 , further comprising:
transmitting, to the base station, a first signal for requesting an uplink resource for reporting the BF information based on the detection of the occurrence of the BF in the at least one of the plurality of cells; and
receiving a second signal for allocating the uplink resource for reporting the BF information from the base station in response to the first signal.
8. The method of claim 1 ,
wherein the BF information is transmitted through a physical uplink control channel (PUCCH) or a physical uplink shared channel (PUSCH).
9. The method of claim 1 ,
wherein the detection of the occurrence of the BF in the at least one of the plurality of cells is performed based on qualities of all control resource set (CORESET) beams related to each of the at least one cell or all beams configured for beam failure detection (BFD) being less than or equal to a predetermined threshold.
10. The method of claim 1 , wherein the plurality of cells configured for the terminal comprises a primary cell or a secondary cell.
11. A terminal configured with a plurality of cells and configured to report a beam failure (BF) in a wireless communication system, the terminal comprising:
at least one transmitter;
at least one receiver;
at least one processor; and
at least one memory operatively coupled to the at least one processor and configured to store instructions causing, when executed, the at least one processor to perform a specific operation,
wherein the specific operation comprises:
receiving, from a base station, configuration information for a plurality of trigger states related to aperiodic channel state information (CSI) reporting; and
based on (i) a control signal related to one trigger state among the plurality of trigger states, and (ii) detection of occurrence of the BF in at least one of the plurality of cells, transmitting, to a base station, BF information based on beam information related to at least one second cell in which the BF has occurred among one or more first cells related to the one trigger state,
wherein the BF information includes (i) identification information about the at least one second cell in which the BF has occurred and (ii) new beam information related to each of the at least one second cell in which the BF has occurred, and
wherein the identification information about the at least one second cell in which the BF has occurred has a bit size determined based on a number of the plurality of cells configured for the terminal.
12. A base station including a plurality of cells and configured to receive beam failure (BF) information in a wireless communication system, the base station comprising:
at least one transmitter;
at least one receiver;
at least one processor; and
at least one memory operatively coupled to the at least one processor and configured to store instructions causing, when executed, the at least one processor to perform a specific operation,
wherein the specific operation comprises:
transmitting, to a terminal, configuration information for a plurality of trigger states related to aperiodic channel state information (CSI) reporting;
based on (i) one of the plurality of trigger states and (ii) a BF occurring in at least one of a plurality of cells configured for the terminal, receiving, from the terminal, the BF information based on beam information related to at least one second cell in which the BF has occurred among one or more first cells related to the one trigger state; and
recognizing the occurrence of the BF in the at least one second cell based on the BF information,
wherein the BF information includes (i) identification information about the at least one second cell in which the BF has occurred and (ii) new beam information related to each of the at least one second cell in which the BF has occurred, and
wherein the identification information about the at least one second cell in which the BF has occurred has a bit size determined based on a number of the plurality of cells configured for the terminal.