Latency reduction for beam failure recovery
The present application relates to devices and components including apparatus, systems, and methods for latency reduction for beam failure recovery (BFR), with respect to transmit-receive point (TRP)-specific BFR.
1 . A method comprising:
processing configuration information received from a network, the configuration information to configure: a first list of beam failure detection (BFD) reference signals (RSs) for a bandwidth part (BWP) of a serving cell, and a second list of BFD RSs for the BWP of the serving cell;
processing a media access control (MAC) control element (CE) received from the network, the MAC CE to indicate a BFD RS within the first list or within the second list to be used for BFD;
determining a radio link quality using the indicated BFD RS; and
determining whether a beam failure is detected based on the radio link quality.
2 . The method of claim 1 , wherein the BWP is a first BWP, and wherein:
the first list is for the first BWP, and the method further includes receiving a third list of BFD RSs for a second BWP; or
the first list is for a first component carrier (CC), and the method further includes receiving a third list of BFD RSs for a second CC; or
the first list is for a first group of CCs, and the method further includes receiving a third list of BFD RSs for a second group of CCs.
3 . The method of claim 1 , wherein the BFD RS is a first BFD RS, and the method further comprising:
selecting a second BFD RS based on the second BFD RS being quasi-co-located (QCLed) with an RS configured in a transmission configuration indicator (TCI) state.
4 . The method of claim 3 , the method further comprising:
identifying a plurality of BFD RSs that are QCLed with the RS configured in the TCI state; and
selecting a third BFD RS from the plurality of BFD RSs based on a periodicity of the third BFD RS or a density of the third BFD RS.
5 . The method of claim 4 , the method further comprising:
selecting a fourth BFD RS based on the fourth BFD RS having a smallest periodicity of the plurality of BFD RSs; or
determining the fourth BFD RS has a priority equal to a fifth BFD RS of the plurality of BFD RSs, and selecting the fourth BFD RS based further on an index of the fourth BFD RS.
6 . The method of claim 1 , the method further comprising receiving an indication of a number of lists of BFD RSs to be received.
7 . The method of claim 1 , the method further comprising:
generating a beam failure recovery request (BFRQ) that is to indicate the BFD RS;
receiving a beam failure request response (BFRR); and
subsequent to a predetermined delay period after receiving the BFRR, resetting a beam for a control resource set (CORESET) based on a beam identified in the BFRQ.
8 . An apparatus comprising:
processing circuitry to:
process configuration information, received from a network, the configuration information to configure: a first list of beam failure detection (BFD) reference signals (RSs) for a bandwidth part (BWP) of a serving cell, and a second list of BFD RSs for the BWP of the serving cell,
process a media access control (MAC) control element (CE) received from the network, the MAC CE indicating a BFD RS within the first list or within the second list to be used for BFD,
determine a radio link quality based on the indicated BFD RS, and
determine whether a beam failure is detected based on the radio link quality; and
interface circuitry coupled with the processing circuitry to receive the MAC CE.
9 . The apparatus of claim 8 , wherein the processing circuitry is further to:
generate an acknowledgement (ACK) that the MAC CE was received; and
subsequent to a predetermined delay period after a last symbol of the ACK is sent, apply the BFD RS.
10 . The apparatus of claim 8 , wherein the processing circuitry is further to reset a BFD counter based on the MAC CE.
11 . The apparatus of claim 8 , wherein the processing circuitry is further to select among the BFD RSs of the first list according to a priority rule, wherein the priority rule is based on search space periodicity, CORESET index, BFD RS periodicity, BFD RS density, BFD RS bandwidth, or BFD RS index.
12 . The apparatus of claim 11 , wherein the priority rule is based on a monitoring periodicity of search space sets associated with control resource sets (CORESETs) that correspond to BFD RSs among the first list.
13 . The apparatus of claim 11 , wherein the priority rule is based on a transmit-receive point (TRP) index.
14 . The apparatus of claim 8 , wherein the processing circuitry is further to:
generate the BFR MAC CE to indicate a serving cell index based on determining whether the beam failure is detected based on the radio link quality.
15 . A method, comprising:
outputting, for transmission, configuration information to a user equipment (UE), the configuration information including a first list of beam failure detection (BFD) reference signals (RSs) for a bandwidth part (BWP) of a serving cell and a second list of BFD RSs to be transmitted to the UE for the BWP of the serving cell;
determining a BFD RS within the first list or within the second list to be used for BFD;
outputting, for transmission, a media access control (MAC) control element (CE) to indicate the determined BFD RS from the first list or the second list; and
process a beam failure recovery (BFR) MAC CE from the UE, the BFR MAC CE to indicate BFD information based on the indicated BFD RS.
16 . The method media of claim 15 , wherein:
the BWP is a first BWP, and wherein:
the first list is for the first BWP, and
the instructions that, when executed, further cause the processing circuitry to send a third list of BFD RSs for a second BWP.
17 . The method of claim 15 , wherein:
the first list is for a first component carrier (CC), and
the instructions that, when executed, further cause the processing circuitry to send a third list of BFD RSs for a second CC.
18 . The method of claim 15 , wherein the BFD RS is quasi-co-located with an RS configured in a TCI state.
19 . The method of claim 15 , wherein the BFR MAC CE indicates a transmit-receive point (TRP) index that identifies a first TRP or a second TRP.
20 . The method of claim 15 , wherein the BFR MAC CE indicates a first BFD RS.