specviewer.org TS 38.331 ASN.1 index BeamFailureRecoveryConfig

BeamFailureRecoveryConfig

RRC IE · TS 38.331 v19.4.0 (2026-09) · clause 6.3.2

BeamFailureRecoveryConfig is an RRC information element of 3GPP TS 38.331 (38331), the 5G NR Radio Resource Control (RRC) protocol.

First seen v15.1.0 (2018-04) · Last changed v19.0.0 (2025-10)

Definition

The IE BeamFailureRecoveryConfig is used to configure the UE with RACH resources and candidate beams for beam failure recovery in case of beam failure detection. See also TS 38.321 [3], clause 5.1.1.

BeamFailureRecoveryConfig ::=       SEQUENCE {
    rootSequenceIndex-BFR               INTEGER (0..137)                                                          OPTIONAL, -- Need M
    rach-ConfigBFR                      RACH-ConfigGeneric                                                        OPTIONAL, -- Need M
    rsrp-ThresholdSSB                   RSRP-Range                                                                OPTIONAL, -- Need M
    candidateBeamRSList                 SEQUENCE (SIZE(1..maxNrofCandidateBeams)) OF PRACH-ResourceDedicatedBFR   OPTIONAL, -- Need M
    ssb-perRACH-Occasion                ENUMERATED {oneEighth, oneFourth, oneHalf, one, two,
        four, eight, sixteen}                                      OPTIONAL, -- Need M
    ra-ssb-OccasionMaskIndex            INTEGER (0..15)                                                           OPTIONAL, -- Need M
    recoverySearchSpaceId               SearchSpaceId                                                             OPTIONAL, -- Need R
    ra-Prioritization                   RA-Prioritization                                                         OPTIONAL, -- Need R
    beamFailureRecoveryTimer            ENUMERATED {ms10, ms20, ms40, ms60, ms80, ms100, ms150, ms200}            OPTIONAL, -- Need M
    ...,
    [[
        msg1-SubcarrierSpacing              SubcarrierSpacing                                                         OPTIONAL  -- Need M
    ]],
    [[
        ra-PrioritizationTwoStep-r16        RA-Prioritization                                                         OPTIONAL, -- Need R
        candidateBeamRSListExt-v1610        SetupRelease{ CandidateBeamRSListExt-r16 }                                OPTIONAL  -- Need M
    ]],
    [[
        spCell-BFR-CBRA-r16                 ENUMERATED {true}                                                         OPTIONAL  -- Need R
    ]],
    [[
        ra-OccasionType-r19                 ENUMERATED {sbfd}                                                         OPTIONAL  -- Need S
    ]]
}

Candidate change requests of v19.0.0

The CRs whose title or cover names this change, strong and likely matches only.

Fields (14)

FieldDescription
rootSequenceIndex-BFR
INTEGER (0..137) · OPTIONAL Need M
PRACH root sequence index (see TS 38.211 [16], clause 6.3.3.1) for beam failure recovery.
rach-ConfigBFR
RACH-ConfigGeneric · OPTIONAL Need M
Configuration of random access parameters for BFR.
rsrp-ThresholdSSB
RSRP-Range · OPTIONAL Need M
since v15.2.0
L1-RSRP threshold used for determining whether a candidate beam may be used by the UE to attempt contention free random access to recover from beam failure (see TS 38.213 [13], clause 6).
candidateBeamRSList
SEQUENCE (SIZE(1..maxNrofCandidateBeams)) OF PRACH-ResourceDedicatedBFR · OPTIONAL Need M
Set of reference signals (CSI-RS and/or SSB) identifying the candidate beams for recovery and the associated RA parameters. This set includes all elements of candidateBeamRSList (without suffix) and all elements of candidateBeamRSListExt-v1610 . The UE maintains candidateBeamRSList and candidateBeamRSListExt-v1610 separately: Receiving candidateBeamRSListExt-v1610 set to release releases only the entries that were configured by candidateBeamRSListExt-v1610 , and receiving candidateBeamRSListExt-v1610 set to setup replaces only the entries that were configured by candidateBeamRSListExt-v1610 with the newly signalled entries. The network configures these reference signals to be within the linked DL BWP (i.e., within the DL BWP with the same bwp-Id ) of the UL BWP in which the BeamFailureRecoveryConfig is provided.
ssb-perRACH-Occasion
ENUMERATED {oneEighth, oneFourth, oneHalf, one, two, four, eight, sixteen} · OPTIONAL Need M
since v15.2.0
Number of SSBs per RACH occasion for CF-BFR, see TS 38.213 [13], clause 8.1.
ra-ssb-OccasionMaskIndex
INTEGER (0..15) · OPTIONAL Need M
Explicitly signalled PRACH Mask Index for RA Resource selection in TS 38.321 [3]. The mask is valid for all SSB resources.
recoverySearchSpaceId
SearchSpaceId · OPTIONAL Need R
Search space to use for BFR RAR. The network configures this search space to be within the linked DL BWP (i.e., within the DL BWP with the same bwp-Id ) of the UL BWP in which the BeamFailureRecoveryConfig is provided. The CORESET associated with the recovery search space cannot be associated with another search space. Network always configures the UE with a value for this field when contention free random access resources for BFR are configured.
ra-Prioritization
RA-Prioritization · OPTIONAL Need R
since v15.2.0
beamFailureRecoveryTimer
ENUMERATED {ms10, ms20, ms40, ms60, ms80, ms100, ms150, ms200} · OPTIONAL Need M
since v15.2.0
Timer for beam failure recovery timer. Upon expiration of the timer the UE does not use CFRA for BFR. Value in ms. Value ms10 corresponds to 10 ms, value ms20 corresponds to 20 ms, and so on.
msg1-SubcarrierSpacing
SubcarrierSpacing · OPTIONAL Need M
since v15.8.0
Subcarrier spacing for contention free beam failure recovery (see TS 38.211 [16], clause 5.3.2). Only the following values are applicable depending on the used frequency: FR1/FR1-NTN: 15 or 30 kHz FR2-1/FR2-NTN: 60 or 120 kHz FR2-2: 120, 480, or 960 kHz
ra-PrioritizationTwoStep-r16
RA-Prioritization · OPTIONAL Need R
since v16.0.0
Parameters which apply for prioritized 2-step random access procedure for BFR (see TS 38.321 [3], clause 5.1.1).
candidateBeamRSListExt-v1610
SetupRelease{ CandidateBeamRSListExt-r16 } · OPTIONAL Need M
since v16.1.0
Set of reference signals (CSI-RS and/or SSB) identifying the candidate beams for recovery and the associated RA parameters. This set includes all elements of candidateBeamRSList (without suffix) and all elements of candidateBeamRSListExt-v1610 . The UE maintains candidateBeamRSList and candidateBeamRSListExt-v1610 separately: Receiving candidateBeamRSListExt-v1610 set to release releases only the entries that were configured by candidateBeamRSListExt-v1610 , and receiving candidateBeamRSListExt-v1610 set to setup replaces only the entries that were configured by candidateBeamRSListExt-v1610 with the newly signalled entries. The network configures these reference signals to be within the linked DL BWP (i.e., within the DL BWP with the same bwp-Id ) of the UL BWP in which the BeamFailureRecoveryConfig is provided.
spCell-BFR-CBRA-r16
ENUMERATED {true} · OPTIONAL Need R
since v16.4.0
Indicates that UE is configured to send MAC CE for SpCell BFR as specified in TS38.321 [3].
ra-OccasionType-r19
ENUMERATED {sbfd} · OPTIONAL Need S
since v19.0.0
Indicates that SBFD aware UE (see TS 38.300 [2], clause 23.1) shall use the second PRACH occasions (see TS 38.213 [13], clause 8) for CFRA or for the fallback CBRA, as specified in clause 5.1.2 in TS 38.321 [3]. If absent, the first PRACH occasions shall be used.

Used by (1)

Uses (9)

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