Method and apparatus for beam failure detection, request, and recovery under a unified TCI framework
Methods and apparatuses for beam failure detection, request, and recovery under a unified transmission configuration indication (TCI) framework in a wireless communication system. A method for operating a user equipment (UE) includes receiving information associated with a transmission configuration indication (TCI) state for the UE and identifying, based on the information, an uplink (UL) TCI state or a joint downlink (DL) and UL TCI state for a physical uplink control channel (PUCCH). The method further includes determining, based on the UL TCI state or the joint DL and UL TCI state for the PUCCH, a first beam failure detection (BFD) reference signal (RS) to monitor and monitoring for an UL beam failure based on the first BFD RS.
1 . A user equipment (UE) in a wireless communication system, the UE comprising:
a transceiver; and
a processor operably controller coupled with the transceiver, and configured to:
receive, from a base station, information associated with a transmission configuration indication (TCI) state, wherein the information associated with the TCI state indicates a set of beam failure detection-reference signal (BFD-RS) for monitoring for an uplink (UL) beam failure and a downlink (DL) beam failure,
based on the information associated with the TCI state, identify a UL TCI state or a joint DL and UL TCI state for a physical uplink control channel (PUCCH),
based on the UL TCI state or the joint DL and UL TCI state for the PUCCH, determine a first BFD-RS for monitoring the UL beam failure from the set of BFD-RS and monitor the UL beam failure based on the first BFD RS,
based on the information associated with the TCI state, identify a DL TCI state or a joint DL and UL TCI state for a physical downlink control channel (PDCCH),
based on the UL TCI state or the joint DL and UL TCI state for the PDCCH, determine a second BFD-RS for monitoring the DL beam failure from the set of BFD-RS, and
monitor for the DL beam failure based on the second BFD-RS.
2 . The UE of claim 1 , wherein the processer controller is further configured to:
in case that a radio link quality of the first BFD-RS is worse than a Qout, increase a first beam failure index (BFI) count in a first BFI counter for the first BFD-RS, and
in case that the first BFI counter reaches a maximum number of a first BFI counts, declare the UL beam failure.
3 . The UE of claim 1 , wherein the controller is further configured to:
in case that a radio link quality of the second BFD-RS is worse than a Qout, increase a second beam failure index (BFI) count in a second BFI counter for the set of BFD-RS, and
in case that the second BFI counter reaches a maximum number of a second BFI counts, declare the DL beam failure.
4 . The UE of claim 1 , wherein the controller is further configured to:
based on a received new beam identification-reference signal (NBI-RS) set, identify a set of new beam identification (NBI) RSs for recovering the UL beam failure and the DL beam failure, and
based on the set of NBI RSs, determine a UL beam or a DL beam for recovery.
5 . A base station in a wireless communication system, the base station comprising:
a transceiver; and
a controller coupled with the transceiver, and configured to:
transmit, to a user equipment (UE), information associated with a transmission configuration indication (TCI) state, wherein the information associated with the TCI state indicates a set of beam failure detection-reference signal (BFD-RS) for monitoring for an uplink (UL) beam failure and a downlink (DL) beam failure,
transmit, to the UE, a first BFD-RS for the UL beam failure from the set of BFD-RS, wherein the first BFD-RS is based on a UL TCI state or a joint DL and UL TCI state for a physical uplink control channel (PUCCH), and
transmit, to the UE, a second BFD-RS for the UL beam failure from the set of BFD-RS, wherein the second BFD-RS is based on a DL TCI state or the joint DL and UL TCI state for a physical downlink control channel (PDCCH).
6 . The base station of claim 5 , wherein the UL beam failure is determined in case that a first beam failure index (BFI) counter for the first BFD-RS reaches a maximum number of first BFI counts,
wherein a first BFI count in the first BFI counter is increased in case that a radio link quality of the first BFD-RS is worse than a Qout,
wherein the DL beam failure is determined in case that a second BFI counter for the second BFD-RS reaches a maximum number of second BFI counts, and
wherein a second BFI count in the second BFI counter is increased in case that a radio link quality of the second BFD-RS is worse than a Qout.
7 . The base station of claim 5 , wherein the controller is further configured to:
based on the first BFD-RS, receive, from the UE, first information indicating the UL beam failure, and
based on the second BFD-RS, receive, from the UE, second information indicating the DL beam failure.
8 . A method for operating performed by a user equipment (UE) in a wireless communication system, the method comprising:
receiving, from a base station, information associated with a transmission configuration indication (TCI) state, wherein the information associated with the TCI state indicates a set of beam failure detection-reference signal (BFD-RS) for monitoring for an uplink (UL) beam failure and a downlink (DL) beam failure;
based on the information associated with the TCI state, identifying a UL TCI state or a joint DL and UL TCI state for a physical uplink control channel (PUCCH);
based on the UL TCI state or the joint DL and UL TCI state for the PUCCH, determining a first BFD-RS for monitoring the UL beam failure from the set of BFD-RS;
monitoring the UL beam failure based on the first BFD-RS;
based on the information associated with the TCI state, identifying a DL TCI state or a joint DL and UL TCI state for a physical downlink control channel (PDCCH);
based on the DL TCI state or the joint DL and UL TCI state for the PDCCH, determining a second BFD-RS for monitoring the DL beam failure from the set of BFD-RS; and
monitoring for the DL beam failure based on the second BFD-RS.
9 . The method of claim 8 , further comprising:
in case that a radio link quality of the first BFD-RS is worse than a Qout, increasing a first beam failure index (BFI) count in a first BFI counter for the first BFD-RS; and
in case that the first BFI counter reaches a maximum number of a first BFI counts, declaring the UL beam failure.
10 . The method of claim 8 , further comprising:
in case that a radio link quality of the second BFD-RS is worse than a Qout, increasing a second beam failure index (BFI) count in a second BFI counter for the set of BFD-RS; and
in case that the second BFI counter reaches a maximum number of a second BFI counts, declaring the DL beam failure.
11 . The method of claim 8 , further comprising:
based on a received new beam identification-reference signal (NBI-RS) set, identifying, a set of new beam identification (NBI) RSs for recovering the UL beam failure and the DL beam failure; and
based on the set of NBI RSs, determining a UL beam or a DL beam for recovery.