Method for carrying out beam failure recovery in wireless communication system and device therefor

A method of performing, by a base station (BS), a beam failure recovery in a wireless communication system, the method comprising:

• transmitting, to a user equipment (UE), information related to a new beam identification for the beam failure recovery;
• and
• receiving a beam failure recovery request from the UE based on a Physical Random Access Channel (PRACH) resource,
• wherein the PRACH resource includes a first PRACH resource and a second PRACH resource,
• wherein the first PRACH resource and the second PRACH resource are associated with a Synchronization Signal block (SSB),
• wherein a channel state information (CSI)-reference signal (RS) is spatially quasi co-located (QCL) with the SSB,
• wherein, based on the new beam being the SSB, the beam failure recovery request is based on the first PRACH resource,
• wherein, based on the new beam being the CSI-RS, the beam failure recovery request is based on the second PRACH resource associated with the SSB and different from the first PRACH resource, and
• wherein, based on both the SSB and the CSI-RS being identified as the new beam, the beam failure recovery request is transmitted based on the second PRACH resource associated with the SSB and different from the first PRACH resource.

A user equipment (UE) configured to perform a beam failure recovery in a wireless communication system, the UE comprising:

• at least one transceiver;
• at least one processor;
• and
• at least one memory operably connectable to the at least one processor and storing instructions that, based on being executed by the at least one processor, perform operations comprising:
• detecting a beam failure;
• identifying a new beam for the beam failure recovery;
• and
• transmitting a beam failure recovery request to a base station based on a Physical Random Access Channel (PRACH) resource,
• wherein the PRACH resource includes a first PRACH resource and a second PRACH resource,
• wherein the first PRACH resource and the second PRACH resource are associated with a Synchronization Signal block (SSB),
• wherein a channel state information (CSI)-reference signal (RS) is spatially quasi co-located (QCL) with the SSB,
• wherein, based on the SSB being identified as the new beam, the beam failure recovery request is transmitted based on the first PRACH resource,
• wherein, based on the CSI-RS being identified as the new beam, the beam failure recovery request is transmitted based on the second PRACH resource associated with the SSB and different from the first PRACH resource, and
• wherein, based on both the SSB and the CSI-RS being identified as the new beam, the beam failure recovery request is transmitted based on the second PRACH resource associated with the SSB and different from the first PRACH resource.