9 Specified and default radio configurations

38.3313GPPNRProtocol specificationRadio Resource Control (RRC)Release 17TS

Specified and default configurations are configurations of which the details are specified in the standard. Specified configurations are fixed while default configurations can be modified using dedicated signalling. The default value for the parameters not listed in following clauses shall be set such as the corresponding features are not configured, i.e. release or false unless explicitly stated otherwise.

NOTE: The UE applies the default values specified in the field description of ASN.1 parameters only when the parent IE is present. Hence, the UE does not apply all default values in field descriptions when it applies the "default radio configuration" in accordance with this clause.

9.1 Specified configurations

9.1.1 Logical channel configurations

9.1.1.1 BCCH configuration

Parameters

Name	Value	Semantics description	Ver
SDAP configuration	Not used
PDCP configuration	Not used
RLC configuration	TM
Logical channel configuration	Not used

NOTE: RRC will perform padding, if required due to the granularity of the TF signalling, as defined in 8.5.

9.1.1.2 CCCH configuration

Parameters

Name	Value	Semantics description	Ver
SDAP configuration	Not used
PDCP configuration	Not used
RLC configuration	TM
Logical channel configuration
>priority	1	Highest priority
>prioritisedBitRate	infinity
>bucketSizeDuration	ms1000
>logicalChannelGroup	0

9.1.1.3 PCCH configuration

Parameters

Name	Value	Semantics description	Ver
SDAP configuration	Not used
PDCP configuration	Not used
RLC configuration	TM
Logical channel configuration	Not used

NOTE: RRC will perform padding, if required due to the granularity of the TF signalling, as defined in 8.5.

9.1.1.4 SCCH configuration

Parameters that are specified for unicast of NR sidelink communication, which is used for the sidelink signalling radio bearer of PC5-RRC message. The SL-SRB using this SCCH configuration is named as SL-SRB3.

Name	Value	Semantics description	Ver
PDCP configuration
>t-Reordering	Undefined	Selected by the receiving UE, up to UE implementation
>pdcp-SN-Size	12
RLC configuration		AM RLC
>sn-FieldLength	12
>t-Reassembly	Undefined	Selected by the receiving UE, up to UE implementation
>t-PollRetransmit	Undefined	Selected by the transmitting UE, up to UE implementation
>pollPDU	Undefined	Selected by the transmitting UE, up to UE implementation
>pollByte	Undefined	Selected by the transmitting UE, up to UE implementation
>maxRetxThreshold	Undefined	Selected by the transmitting UE, up to UE implementation
>t-StatusProhibit	Undefined	Selected by the receiving UE, up to UE implementation
>logicalChannelIdentity	3
MAC configuration
>priority	1
>prioritisedBitRate	infinity
>logicalChannelGroup	0
>schedulingRequestId	0	The scheduling request configuration with this value is applicable for this SCCH if configured by the network.
>sl-HARQ-FeedbackEnabled	Undefined	Selected by the transmitting UE, up to UE implementation

Parameters that are specified of NR sidelink communication, which is used for the sidelink signalling radio bearer of unprotected PC5-S message (e.g. Direct Link Establishment Request, TS 24.587 [57]). The SL-SRB using this SCCH configuration is named as SL-SRB0.

Name	Value	Semantics description	Ver
PDCP configuration
>t-Reordering	Undefined	Selected by the receiving UE, up to UE implementation
>pdcp-SN-Size	12
RLC configuration		UM RLC
>sn-FieldLength	6
>t-Reassembly	Undefined	Selected by the receiving UE, up to UE implementation
>logicalChannelIdentity	0
MAC configuration
>priority	1
>prioritisedBitRate	infinity
>logicalChannelGroup	0
>schedulingRequestId	0	The scheduling request configuration with this value is applicable for this SCCH if configured by the network.
>sl-HARQ-FeedbackEnabled	Undefined	Selected by the transmitting UE, up to UE implementation

Parameters that are specified for unicast of NR sidelink communication, which is used for the sidelink signalling radio bearer of PC5-S message establishing PC5-S security (e.g. Direct Link Security Mode Command and Direct Link Security Mode Complete, TS 24.587 [57]). The SL-SRB using this SCCH configuration is named as SL-SRB1.

Name	Value	Semantics description	Ver
PDCP configuration
>t-Reordering	Undefined	Selected by the receiving UE, up to UE implementation
>pdcp-SN-Size	12
RLC configuration		AM RLC
>sn-FieldLength	12
>t-Reassembly	Undefined	Selected by the receiving UE, up to UE implementation
>t-PollRetransmit	Undefined	Selected by the transmitting UE, up to UE implementation
>pollPDU	Undefined	Selected by the transmitting UE, up to UE implementation
>pollByte	Undefined	Selected by the transmitting UE, up to UE implementation
>maxRetxThreshold	Undefined	Selected by the transmitting UE, up to UE implementation
>t-StatusProhibit	Undefined	Selected by the receiving UE, up to UE implementation
>logicalChannelIdentity	1
MAC configuration
>priority	1
>prioritisedBitRate	infinity
>logicalChannelGroup	0
>schedulingRequestId	0	The scheduling request configuration with this value is applicable for this SCCH if configured by the network.
>sl-HARQ-FeedbackEnabled	Undefined	Selected by the transmitting UE, up to UE implementation

Parameters that are specified for unicast of NR sidelink communication, which is used for the sidelink signalling radio bearer of protected PC5-S message except Direct Link Security Mode Complete. The SL-SRB using this SCCH configuration is named as SL-SRB2.

Name	Value	Semantics description	Ver
PDCP configuration
>t-Reordering	Undefined	Selected by the receiving UE, up to UE implementation
>pdcp-SN-Size	12
RLC configuration		AM RLC
>sn-FieldLength	12
>t-Reassembly	Undefined	Selected by the receiving UE, up to UE implementation
>t-PollRetransmit	Undefined	Selected by the transmitting UE, up to UE implementation
>pollPDU	Undefined	Selected by the transmitting UE, up to UE implementation
>pollByte	Undefined	Selected by the transmitting UE, up to UE implementation
>maxRetxThreshold	Undefined	Selected by the transmitting UE, up to UE implementation
>t-StatusProhibit	Undefined	Selected by the receiving UE, up to UE implementation
>logicalChannelIdentity	2
MAC configuration
>priority	1
>prioritisedBitRate	infinity
>logicalChannelGroup	0
>schedulingRequestId	0	The scheduling request configuration with this value is applicable for this SCCH if configured by the network.
>sl-HARQ-FeedbackEnabled	Undefined	Selected by the transmitting UE, up to UE implementation

Parameters that are specified for NR sidelink discovery, which is used for the sidelink signalling radio bearer of NR sidelink discovery messages (e.g., Announcement message, Solicitation message and Response message, see TS 23.304 [65]). The SL-SRB using this SCCH configuration is named as SL-SRB4.

Name	Value	Semantics description	Ver
PDCP configuration
>t-Reordering	Undefined	Selected by the receiving UE, up to UE implementation
>pdcp-SN-Size	12
RLC configuration		UM RLC
>sn-FieldLength	6
>t-Reassembly	Undefined	Selected by the receiving UE, up to UE implementation
>logicalChannelIdentity	58
MAC configuration
>priority	1
>prioritisedBitRate	infinity
>logicalChannelGroup	0
>schedulingRequestId	0	The scheduling request configuration with this value is applicable for this SCCH if configured by the network.
>sl-HARQ-FeedbackEnabled	disabled	HARQ feedback is not supported for NR sidelink discovery transmission

Parameters that are specified for NR sidelink L2 U2N Relay operations, which is used for the PC5 Relay RLC channel for Remote UE’s SRB0 message transmission. The PC5 Relay RLC channel using this configuration is named as SL-RLC0.

Name	Value	Semantics description	Ver
RLC configuration		AM
>sn-FieldLength	12
>t-Reassembly	Undefined	Selected by the receving UE, up to UE implementation
>t-PollRetransmit	Undefined	Selected by the transmitting UE, up to UE implementation
>pollPDU	Undefined	Selected by the transmitting UE, up to UE implementation
>pollByte	Undefined	Selected by the transmitting UE, up to UE implementation
>maxRetxThreshold	Undefined	Selected by the transmitting UE, up to UE implementation
>t-StatusProhibit	Undefined	Selected by the receiving UE, up to UE implementation
>logicalChannelIdentity	56
MAC configuration
>priority	1
>proritisedBitRate	Inifinity
>logicalChannelGroup	0
>schedulingRequestId	0	The scheduling request configuration with this value is applicable for this SCCH if configured by the network. The scheduling request configuration is not applicable to L2 U2N Remote UE.
>sl-HARQ-FeedbackEnabled	Undefined	Selected by the transmitting UE, up to UE implementation

9.1.1.5 STCH configuration

Parameters that are specified for NR sidelink communication, which is used for the sidelink data radio bearer.

Name	Value	Semantics description	Ver
PDCP configuration
>t-Reordering	Undefined	Selected by the receiving UE, up to UE implementation
>pdcp-SN-Size	12	For broadcast and groupcast of NR sidelink communication
>maxCID	15	For broadcast and groupcast of NR sidelink communication
>profiles
RLC configuration		For broadcast and groupcast of NR sidelink communication, uni-directional UM RLC UM window size is set to 32
>t-Reassembly	Undefined	Selected by the receiving UE, up to Up to UE implementation
>sn-FieldLength	6	For broadcast and groupcast of NR sidelink communication
>logicalChannelIdentity	Undefined	Selected by the transmitting UE, up to UE implementation
MAC configuration
>priority

9.1.1.6 MCCH configuration

Parameters that are specified for MCCH.

Name	Value	Semantics description	Ver
RLC configuration		UM RLC
>sn-FieldLength	6
>t-Reassembly	ms0

9.1.1.7 MTCH configuration for MBS broadcast

Parameters that are specified for MBS broadcast MTCH.

Name	Value	Semantics description	Ver
PDCP configuration
>t-Reordering	ms0
>pdcp-SN-SizeDL	18
RLC configuration		UM RLC
>sn-FieldLength	12
>t-Reassembly	ms0

9.1.2 Void

9.2 Default radio configurations

The following clauses only list default values for REL-15 parameters included in protocol version v15.3.0. For all fields introduced in a later protocol version, the default value is "released" or "false" unless explicitly specified otherwise. If the UE is to apply default configuration while it is configured with some critically extended fields, the UE shall apply the original version of those fields with only default values.

NOTE 1: In general, the signalling should preferably support a "release" option for fields introduced after v15.3.0. The "value not applicable" should be used restrictively, mainly limited to for fields which value is relevant only if another field is set to a value other than its default.

NOTE 2: For parameters in ServingCellConfig, the default values are specified in the corresponding specification.

9.2.1 Default SRB configurations

Parameters

Name	Value				Semantics description	Ver
	SRB1	SRB2		SRB3
PDCP-Config >t-Reordering	infinity
RLC-Config CHOICE	Am
ul-AM-RLC >sn-FieldLength >t-PollRetransmit >pollPDU >pollByte >maxRetxThreshold	size12 ms45 infinity infinity t8
dl-AM-RLC >sn-FieldLength >t-Reassembly >t-StatusProhibit	size12 ms35 ms0
logicalChannelIdentity	1	2	3
LogicalChannelConfig
>priority	1	3	1
>prioritisedBitRate	infinity
>logicalChannelGroup	0

9.2.2 Default MAC Cell Group configuration

Parameters

Name	Value	Semantics description	Ver
MAC Cell Group configuration
bsr-Config
>periodicBSR-Timer	sf10
>retxBSR-Timer	sf80
phr-Config
>phr-PeriodicTimer	sf10
>phr-ProhibitTimer	sf10
>phr-Tx-PowerFactorChange	dB1

9.2.3 Default values timers and constants

Parameters

Name	Value	Semantics description	Ver
t310	ms1000
n310	n1
t311	ms30000
n311	n1

9.2.4 Default PC5 Relay RLC Channel

Parameters of the PC5 Relay RLC Channel used for Remote UE’s SRB1 RRC message transmission and reception. The PC5 Relay RLC Channel using this configuration is named as SL-RLC1.

Name	Value	Semantics description	Ver
RLC configuration		AM
>sn-FieldLength	12
>t-Reassembly	Undefined	Selected by the receving UE, up to UE implementation
>t-PollRetransmit	Undefined	Selected by the transmitting UE, up to UE implementation
>pollPDU	Undefined	Selected by the transmitting UE, up to UE implementation
>pollByte	Undefined	Selected by the transmitting UE, up to UE implementation
>maxRetxThreshold	Undefined	Selected by the transmitting UE, up to UE implementation
>t-StatusProhibit	Undefined	Selected by the receiving UE, up to UE implementation
>logicalChannelIdentity	57
MAC configuration
>priority	1
>proritisedBitRate	Inifinity
>logicalChannelGroup	0
>schedulingRequestId	0	The scheduling request configuration with this value is applicable for this SCCH if configured by the network.

9.2.5 Default SRAP configurations

Parameters that are used for reception of Remote UE’s RRCResume and RRCReestablishment messages.

Name	Value	Semantics description	Ver
SL SRAP Config
> sl-LocalIdentity	Undefined	SRAP PDUs with any local Identity will be submitted to the SRB1 PDCP entity.
> sl-RemoteUE-RB-Identity	SRB1

9.3 Sidelink pre-configured parameters

This ASN.1 segment is the start of the NR definitions of pre-configured sidelink parameters.

– NR-Sidelink-Preconf

— ASN1START

— TAG-NR-SIDELINK-PRECONF-DEFINITIONS-START

NR-Sidelink-Preconf DEFINITIONS AUTOMATIC TAGS ::=

BEGIN

IMPORTS

SL-RemoteUE-Config-r17,

SL-DRX-ConfigGC-BC-r17,

SL-FreqConfigCommon-r16,

SL-RadioBearerConfig-r16,

SL-RLC-BearerConfig-r16,

SL-EUTRA-AnchorCarrierFreqList-r16,

SL-NR-AnchorCarrierFreqList-r16,

SL-MeasConfigCommon-r16,

SL-UE-SelectedConfig-r16,

TDD-UL-DL-ConfigCommon,

maxNrofFreqSL-r16,

maxNrofSLRB-r16,

maxSL-LCID-r16

FROM NR-RRC-Definitions;

— TAG-NR-SIDELINK-PRECONF-DEFINITIONS-STOP

— ASN1STOP

– SL-PreconfigurationNR

The IE SL-PreconfigurationNR includes the sidelink pre-configured parameters used for NR sidelink communication. Need codes or conditions specified for subfields in SL-PreconfigurationNR do not apply.

SL-PreconfigurationNR information elements

— ASN1START

— TAG-SL-PRECONFIGURATIONNR-START

SL-PreconfigurationNR-r16 ::= SEQUENCE {

sidelinkPreconfigNR-r16 SidelinkPreconfigNR-r16,

…

}

SidelinkPreconfigNR-r16 ::= SEQUENCE {

sl-PreconfigFreqInfoList-r16 SEQUENCE (SIZE (1..maxNrofFreqSL-r16)) OF SL-FreqConfigCommon-r16 OPTIONAL,

sl-PreconfigNR-AnchorCarrierFreqList-r16 SL-NR-AnchorCarrierFreqList-r16 OPTIONAL,

sl-PreconfigEUTRA-AnchorCarrierFreqList-r16 SL-EUTRA-AnchorCarrierFreqList-r16 OPTIONAL,

sl-RadioBearerPreConfigList-r16 SEQUENCE (SIZE (1..maxNrofSLRB-r16)) OF SL-RadioBearerConfig-r16 OPTIONAL,

sl-RLC-BearerPreConfigList-r16 SEQUENCE (SIZE (1..maxSL-LCID-r16)) OF SL-RLC-BearerConfig-r16 OPTIONAL,

sl-MeasPreConfig-r16 SL-MeasConfigCommon-r16 OPTIONAL,

sl-OffsetDFN-r16 INTEGER (1..1000) OPTIONAL,

t400-r16 ENUMERATED{ms100, ms200, ms300, ms400, ms600, ms1000, ms1500, ms2000} OPTIONAL,

sl-MaxNumConsecutiveDTX-r16 ENUMERATED {n1, n2, n3, n4, n6, n8, n16, n32} OPTIONAL,

sl-SSB-PriorityNR-r16 INTEGER (1..8) OPTIONAL,

sl-PreconfigGeneral-r16 SL-PreconfigGeneral-r16 OPTIONAL,

sl-UE-SelectedPreConfig-r16 SL-UE-SelectedConfig-r16 OPTIONAL,

sl-CSI-Acquisition-r16 ENUMERATED {enabled} OPTIONAL,

sl-RoHC-Profiles-r16 SL-RoHC-Profiles-r16 OPTIONAL,

sl-MaxCID-r16 INTEGER (1..16383) DEFAULT 15,

…,

[[

sl-DRX-PreConfigGC-BC-r17 SL-DRX-ConfigGC-BC-r17 OPTIONAL,

sl-TxProfileList-r17 SL-TxProfileList-r17 OPTIONAL,

sl-PreconfigDiscConfig-r17 SL-RemoteUE-Config-r17 OPTIONAL

]]

}

SL-TxProfileList-r17 ::= SEQUENCE (SIZE (1..256)) OF SL-TxProfile-r17

SL-TxProfile-r17 ::= ENUMERATED {drx-Compatible, drx-Incompatible, spare6, spare5, spare4, spare3,spare2, spare1}

SL-PreconfigGeneral-r16 ::= SEQUENCE {

sl-TDD-Configuration-r16 TDD-UL-DL-ConfigCommon OPTIONAL,

reservedBits-r16 BIT STRING (SIZE (2)) OPTIONAL,

…

}

SL-RoHC-Profiles-r16 ::= SEQUENCE {

profile0x0001-r16 BOOLEAN,

profile0x0002-r16 BOOLEAN,

profile0x0003-r16 BOOLEAN,

profile0x0004-r16 BOOLEAN,

profile0x0006-r16 BOOLEAN,

profile0x0101-r16 BOOLEAN,

profile0x0102-r16 BOOLEAN,

profile0x0103-r16 BOOLEAN,

profile0x0104-r16 BOOLEAN

}

— TAG-SL-PRECONFIGURATIONNR-STOP

— ASN1STOP

SL-PreconfigurationNR field descriptions
sl-DRX-PreConfig-GC-BC This field indicates the sidelink DRX configuration for groupcast and broadcast communication, as specified in TS 38.321 [3].
sl-OffsetDFN Indicates the timing offset for the UE to determine DFN timing when GNSS is used for timing reference. Value 1 corresponds to 0.001 milliseconds, value 2 corresponds to 0.002 milliseconds, and so on. If the field is absent, no offset is applied.
sl-PreconfigDiscConfig This field indicates the configuration for discovery message transmission used by NR sidelink U2N Remote UE.
sl-PreconfigEUTRA-AnchorCarrierFreqList This field indicates the EUTRA anchor carrier frequency list, which can provide the NR sidelink communication configuration.
sl-PreconfigFreqInfoList This field indicates the NR sidelink communication and/ or NR sidelink discovery configuration some carrier frequency(ies). In this release, only one SL-FreqConfig can be configured in the list.
sl-PreconfigNR-AnchorCarrierFreqList This field indicates the NR anchor carrier frequency list, which can provide the NR sidelink communication configuration.
sl-RadioBearerPreConfigList This field indicates one or multiple sidelink radio bearer configurations.
sl-RLC-BearerPreConfigList This field indicates one or multiple sidelink RLC bearer configurations.
sl-RoHC-Profiles This field indicates the supported RoHC profiles for NR sidelink communications.
sl-SSB-PriorityNR This field indicates the priority of NR sidelink SSB transmission and reception.
sl-TxProfileList List of one or multiple Tx profiles, which are indicated by upper layer in order of increasing Tx profile pointer identities, indicate the compatibility of supporting SL DRX as specified in TS 38.321 [3].

– End of NR-Sidelink-Preconf

— ASN1START

END

— ASN1STOP

9.4 Radio Information Related to Discovery Message

This clause specifies RRC information elements that are transferred in Discovery Message.

– SL-AccessInfo-L2U2N

The IE SL-AccessInfo-L2U2N includes the radio information included in Discovery Message used for L2 U2N relay operation.

SL-AccessInfo-L2U2N information elements

— ASN1START

— TAG-SL-ACCESSINFO-L2U2N-START

NR-Sidelink-DiscoveryMessage DEFINITIONS AUTOMATIC TAGS ::=

BEGIN

IMPORTS

CellAccessRelatedInfo,

SL-ServingCellInfo-r17

FROM NR-RRC-Definitions;

SL-AccessInfo-L2U2N-r17 ::= SEQUENCE {

cellAccessRelatedInfo-r17 CellAccessRelatedInfo,

sl-ServingCellInfo-r17 SL-ServingCellInfo-r17,

…

}

END

— TAG-SL-ACCESSINFO-L2U2N-STOP

— ASN1STOP