Terminal, radio communication method, base station, and system for beam failure detection
A terminal according to one aspect of the present disclosure includes a receiving section that receives a medium access control-control element (MAC CE) indicating two active transmission configuration indicator (TCI) states for one control resource set, and a control section that, when an information element of a radio link monitoring (RLM) reference signal is not provided, uses a reference signal in at least one TCI state out of the two active TCI states for RLM. According to one aspect of the present disclosure, it is possible to appropriately perform at least one of RLM and BFD.
1 . A terminal comprising:
a transmitter that transmits capability information indicating support of an indication of two transmission configuration indicator (TCI) states for one control resource set (CORESET);
a receiver that receives, for a single frequency network (SFN) scheme, a medium access control-control element (MAC CE) indicating two TCI states for one CORESET; and
a processor that, when a failure detection resource is not provided, uses reference signals in the two TCI states indicated by the MAC CE for beam failure detection (BFD),
wherein the transmitter further transmits a second capability information indicating a maximum number of beam failure detection reference signals (BFD-RSs), wherein the BFD-RSs are determined based on an active TCI state for a CORESET for physical downlink control channel (PDCCH) monitoring, and
wherein when the failure detection resource is not provided and a number of reference signals in multiple active TCI states for multiple CORESETs for PDCCH monitoring is greater than the maximum number, the processor uses, for BFD, a number of the reference signals equal to the maximum number.
2 . The terminal according to claim 1 , wherein the processor determines the number of the reference signals equal to the maximum number, based on monitoring periodicity of multiple search space sets associated with the multiple CORESETs.
3 . A radio communication method for a terminal, comprising:
transmitting capability information indicating support of an indication of two transmission configuration indicator (TCI) states for one control resource set (CORESET);
receiving, for a single frequency network (SFN) scheme, a medium access control-control element (MAC CE) indicating two TCI states for one CORESET;
using, when a failure detection resource is not provided, reference signals in the two TCI states indicated by the MAC CE for beam failure detection (BFD);
transmitting a second capability information indicating a maximum number of beam failure detection reference signals (BFD-RSs), wherein the BFD-RSs are determined based on an active TCI state for a CORESET for physical downlink control channel (PDCCH) monitoring; and
using, for BFD, when the failure detection resource is not provided and a number of reference signals in multiple active TCI states for multiple CORESETs for PDCCH monitoring is greater than the maximum number, a number of the reference signals equal to the maximum number.
4 . A base station comprising:
a receiver that receives capability information indicating support of an indication of two transmission configuration indicator (TCI) states for one control resource set (CORESET);
a transmitter that transmits, for a single frequency network (SFN) scheme, a medium access control-control element (MAC CE) indicating two TCI states for one CORESET; and
a processor that, when not providing a failure detection resource, controls reception of a beam recovery request based on beam failure detection (BFD) using reference signals in the two TCI states indicated by the MAC CE,
wherein the receiver further receives a second capability information indicating a maximum number of beam failure detection reference signals (BFD-RSs), wherein the BFD-RSs are determined based on an active TCI state for a CORESET for physical downlink control channel (PDCCH) monitoring, and
wherein when the failure detection resource is not provided and a number of reference signals in multiple active TCI states for multiple CORESETs for PDCCH monitoring is greater than the maximum number, a number of the reference signals equal to the maximum number is used for BFD.
5 . A system comprising a terminal and a base station, wherein
the terminal comprises:
a transmitter that transmits capability information indicating support of an indication of two transmission configuration indicator (TCI) states for one control resource set (CORESET);
a receiver that receives, for a single frequency network (SFN) scheme, a medium access control-control element (MAC CE) indicating two TCI states for one CORESET; and
a processor that, when a failure detection resource is not provided, uses reference signals in the two TCI states indicated by the MAC CE for beam failure detection (BFD),
wherein the transmitter further transmits a second capability information indicating a maximum number of beam failure detection reference signals (BFD-RSs), wherein the BFD-RSs are determined based on an active TCI state for a CORESET for physical downlink control channel (PDCCH) monitoring, and
wherein when the failure detection resource is not provided and a number of reference signals in multiple active TCI states for multiple CORESETs for PDCCH monitoring is greater than the maximum number, the processor uses, for BFD, a number of the reference signals equal to the maximum number, and
the base station comprises:
a transmitter that transmits the MAC CE.