ServingCellConfigCommonSIB

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

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

First seen v15.3.0 (2018-09) · Last changed v18.2.0 (2024-07)

Definition

The IE ServingCellConfigCommonSIB is used to configure cell specific parameters of a UE's serving cell in SIB1.

ServingCellConfigCommonSIB ::=      SEQUENCE {
    downlinkConfigCommon                DownlinkConfigCommonSIB,
    uplinkConfigCommon                  UplinkConfigCommonSIB                                       OPTIONAL, -- Need R
    supplementaryUplink                 UplinkConfigCommonSIB                                       OPTIONAL, -- Need R
    n-TimingAdvanceOffset               ENUMERATED { n0, n25600, n39936 }                           OPTIONAL, -- Need S
    ssb-PositionsInBurst                SEQUENCE {
        inOneGroup                          BIT STRING (SIZE (8)),
        groupPresence                       BIT STRING (SIZE (8))                                   OPTIONAL  -- Cond FR2-Only
    },
    ssb-PeriodicityServingCell          ENUMERATED {ms5, ms10, ms20, ms40, ms80, ms160},
    tdd-UL-DL-ConfigurationCommon       TDD-UL-DL-ConfigCommon                                      OPTIONAL, -- Cond TDD
    ss-PBCH-BlockPower                  INTEGER (-60..50),
    ...,
    [[
        channelAccessMode-r16               CHOICE {
            dynamic                             NULL,
            semiStatic                          SemiStaticChannelAccessConfig-r16
        }                                                                                               OPTIONAL, -- Cond SharedSpectrum
        discoveryBurstWindowLength-r16      ENUMERATED {ms0dot5, ms1, ms2, ms3, ms4, ms5}               OPTIONAL, -- Need R
        highSpeedConfig-r16                 HighSpeedConfig-r16                                         OPTIONAL  -- Need R
    ]],
    [[
        channelAccessMode2-r17              ENUMERATED {enabled}                                        OPTIONAL, -- Cond SharedSpectrum2
        discoveryBurstWindowLength-v1700    ENUMERATED {ms0dot125, ms0dot25, ms0dot5, ms0dot75, ms1, ms1dot25} OPTIONAL,  -- Need R
        highSpeedConfigFR2-r17              HighSpeedConfigFR2-r17                                      OPTIONAL, -- Need R
        uplinkConfigCommon-v1700            UplinkConfigCommonSIB-v1700                                 OPTIONAL  -- Need R
    ]],
    [[
        enhancedMeasurementNGSO-r17         ENUMERATED {true}                                           OPTIONAL  -- Need R
    ]],
    [[
        ra-ChannelAccess-r17                ENUMERATED {enabled}                                        OPTIONAL  -- Cond SharedSpectrum2
    ]],
    [[
        downlinkConfigCommon-v1760          DownlinkConfigCommonSIB-v1760                               OPTIONAL, -- Need R
        uplinkConfigCommon-v1760            UplinkConfigCommonSIB-v1760                                 OPTIONAL  -- Need R
    ]]
}

Candidate change requests of v18.2.0

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

CR 4746 r1 (strong): Clarification on usage of LEO or NGSO

Fields (23)

Field	Description
downlinkConfigCommon DownlinkConfigCommonSIB
uplinkConfigCommon UplinkConfigCommonSIB · OPTIONAL Need R
supplementaryUplink UplinkConfigCommonSIB · OPTIONAL Need R
n-TimingAdvanceOffset ENUMERATED { n0, n25600, n39936 } · OPTIONAL Need S	The N_TA-Offset to be applied for random access on this serving cell. If the field is absent, the UE applies the value defined for the duplex mode and frequency range of this serving cell. See TS 38.133 [14], table 7.1.2-2/table 7.1C.2-4.
ssb-PositionsInBurst SEQUENCE {	Time domain positions of the transmitted SS-blocks in an SS-burst as defined in TS 38.213 [13], clause 4.1. For operation with shared spectrum channel access in FR1, only inOneGroup is used and the UE interprets this field same as mediumBitmap in ServingCellConfigCommon. The UE assumes that a bit in inOneGroup at position k > $N_{SSB}^{QCL}$ is 0, where $N_{SSB}^{QCL}$ is obtained from MIB as specified in TS 38.213 [13], clause 4.1. For operation with shared spectrum channel access in FR2-2, the m-th bit in groupPresence is set to 0 for m > $N_{SSB}^{QCL}$ /8, where $N_{SSB}^{QCL}$ is obtained from MIB as specified in TS 38.213 [13], clause 4.1.
inOneGroup BIT STRING (SIZE (8))	When maximum number of SS/PBCH blocks per half frame equals to 4 as defined in TS 38.213 [13], clause 4.1, only the 4 leftmost bits are valid; the UE ignores the 4 rightmost bits. When maximum number of SS/PBCH blocks per half frame equals to 8 as defined in TS 38.213 [13], clause 4.1, all 8 bits are valid. The first/ leftmost bit corresponds to SS/PBCH block index 0, the second bit corresponds to SS/PBCH block index 1, and so on. When maximum number of SS/PBCH blocks per half frame equals to 64 as defined in TS 38.213 [13], clause 4.1, all 8 bit are valid; The first/ leftmost bit corresponds to the first SS/PBCH block index in the group (i.e., to SSB index 0, 8, and so on); the second bit corresponds to the second SS/PBCH block index in the group (i.e., to SSB index 1, 9, and so on), and so on. Value 0 in the bitmap indicates that the corresponding SS/PBCH block is not transmitted while value 1 indicates that the corresponding SS/PBCH block is transmitted.
groupPresence BIT STRING (SIZE (8)) · OPTIONAL Cond FR2-Only	This field is present when maximum number of SS/PBCH blocks per half frame equals to 64 as defined in TS 38.213 [13], clause 4.1. The first/leftmost bit corresponds to the SS/PBCH index 0-7, the second bit corresponds to SS/PBCH block 8-15, and so on. Value 0 in the bitmap indicates that the SSBs according to inOneGroup are absent. Value 1 indicates that the SS/PBCH blocks are transmitted in accordance with inOneGroup .
ssb-PeriodicityServingCell ENUMERATED {ms5, ms10, ms20, ms40, ms80, ms160}
tdd-UL-DL-ConfigurationCommon TDD-UL-DL-ConfigCommon · OPTIONAL Cond TDD
ss-PBCH-BlockPower INTEGER (-60..50)	Average EPRE of the resources elements that carry secondary synchronization signals in dBm that the NW used for SSB transmission, see TS 38.213 [13], clause 7.
channelAccessMode-r16 CHOICE { · OPTIONAL Cond SharedSpectrum since v16.0.0	If present, this field indicates which channel access procedures to apply for operation with shared spectrum channel access as defined in TS 37.213 [48]. If the field is configured as "semiStatic", the UE shall apply the channel access procedures for semi-static channel occupancy as described in clause 4.3 in TS 37.213. If the field is configured as "dynamic", the UE shall apply the channel access procedures as defined in TS 37.213, clause 4.1 and 4.2.
dynamic NULL since v16.0.0
semiStatic SemiStaticChannelAccessConfig-r16 since v16.1.0
discoveryBurstWindowLength-r16 ENUMERATED {ms0dot5, ms1, ms2, ms3, ms4, ms5} · OPTIONAL Need R since v16.0.0	Indicates the window length of the discovery burst in ms (see TS 37.213 [48]). The field discoveryBurstWindowLength-v1700 is applicable to SCS 480 kHz and SCS 960 kHz.
highSpeedConfig-r16 HighSpeedConfig-r16 · OPTIONAL Need R since v16.1.0
channelAccessMode2-r17 ENUMERATED {enabled} · OPTIONAL Cond SharedSpectrum2 since v17.0.0	If present, this field indicates that the UE shall apply channel access procedures for operation with shared spectrum channel access in accordance with TS 37.213 [48], clause 4.4 for FR2-2. If absent, the UE shall not apply any channel access procedure. The network always configures this field if channel access procedures are required for the serving cell within this region by regulations.
discoveryBurstWindowLength-v1700 ENUMERATED {ms0dot125, ms0dot25, ms0dot5, ms0dot75, ms1, ms1dot25} · OPTIONAL Need R since v17.0.0	Indicates the window length of the discovery burst in ms (see TS 37.213 [48]). The field discoveryBurstWindowLength-v1700 is applicable to SCS 480 kHz and SCS 960 kHz.
highSpeedConfigFR2-r17 HighSpeedConfigFR2-r17 · OPTIONAL Need R since v17.0.0
uplinkConfigCommon-v1700 UplinkConfigCommonSIB-v1700 · OPTIONAL Need R since v17.0.0
enhancedMeasurementNGSO-r17 ENUMERATED {true} · OPTIONAL Need R since v17.9.0	If the field is present and UE supports the enhanced cell reselection requirements for NTN NGSO in RRC_IDLE/RRC_INACTIVE, the UE shall apply the enhanced cell reselection requirements for NTN NGSO as specified in TS 38.133 [14], clauses 4.2C.2.3 and 4.2C.2.4.
ra-ChannelAccess-r17 ENUMERATED {enabled} · OPTIONAL Cond SharedSpectrum2 since v17.4.0	If present, this field indicates that the UE shall apply channel access procedures before msg1/msgA transmission for operation with shared spectrum channel access in accordance with TS 37.213 [48], clause 4.4.5 for FR2-2.
downlinkConfigCommon-v1760 DownlinkConfigCommonSIB-v1760 · OPTIONAL Need R since v17.6.0
uplinkConfigCommon-v1760 UplinkConfigCommonSIB-v1760 · OPTIONAL Need R since v17.6.0

Used by (1)

SIB1

ServingCellConfigCommonSIB

Definition

Candidate change requests of v18.2.0

Fields (23)

Used by (1)

Uses (9)

In the viewer