ETSI TS 138 331 V15.8.0 (2020-01)

5G; NR; Radio Resource Control (RRC); Protocol specification (3GPP TS 38.331 version 15.8.0 Release 15)

RTS/TSGR-0238331vf80

General Information

• Status: Published
• Publication Date: 16-Jan-2020
• Technical Committee: 3GPP RAN 2 - Radio layer 2 specification and Radio layer 3 RR specification
• Current Stage: 12 - Completion
• Completion Date: 17-Jan-2020

Standards Content (Sample)

TECHNICAL SPECIFICATION
5G;
NR;
Radio Resource Control (RRC);
Protocol specification
(3GPP TS 38.331 version 15.8.0 Release 15)

3GPP TS 38.331 version 15.8.0 Release 15 1 ETSI TS 138 331 V15.8.0 (2020-01)

Reference
RTS/TSGR-0238331vf80
Keywords
5G
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ETSI
3GPP TS 38.331 version 15.8.0 Release 15 2 ETSI TS 138 331 V15.8.0 (2020-01)
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ETSI
3GPP TS 38.331 version 15.8.0 Release 15 3 ETSI TS 138 331 V15.8.0 (2020-01)
Contents
Intellectual Property Rights . 2
Legal Notice . 2
Modal verbs terminology . 2
Foreword . 15
1 Scope . 16
2 References . 16
3 Definitions, symbols and abbreviations . 18
3.1 Definitions . 18
3.2 Abbreviations . 18
4 General . 20
4.1 Introduction . 20
4.2 Architecture . 20
4.2.1 UE states and state transitions including inter RAT . 20
4.2.2 Signalling radio bearers . 22
4.3 Services . 23
4.3.1 Services provided to upper layers . 23
4.3.2 Services expected from lower layers . 23
4.4 Functions . 23
5 Procedures . 24
5.1 General . 24
5.1.1 Introduction. 24
5.1.2 General requirements . 24
5.1.3 Requirements for UE in MR-DC . 25
5.2 System information . 25
5.2.1 Introduction. 25
5.2.2 System information acquisition . 26
5.2.2.1 General UE requirements . 26
5.2.2.2 SIB validity and need to (re)-acquire SIB . 27
5.2.2.2.1 SIB validity . 27
5.2.2.2.2 SI change indication and PWS notification . 27
5.2.2.3 Acquisition of System Information . 28
5.2.2.3.1 Acquisition of MIB and SIB1 . 28
5.2.2.3.2 Acquisition of an SI message . 29
5.2.2.3.3 Request for on demand system information . 29
5.2.2.3.4 Actions related to transmission of RRCSystemInfoRequest message . 30
5.2.2.4 Actions upon receipt of System Information . 30
5.2.2.4.1 Actions upon reception of the MIB . 30
5.2.2.4.2 Actions upon reception of the SIB1 . 31
5.2.2.4.3 Actions upon reception of SIB2 . 33
5.2.2.4.4 Actions upon reception of SIB3 . 34
5.2.2.4.5 Actions upon reception of SIB4 . 34
5.2.2.4.6 Actions upon reception of SIB5 . 35
5.2.2.4.7 Actions upon reception of SIB6 . 35
5.2.2.4.8 Actions upon reception of SIB7 . 35
5.2.2.4.9 Actions upon reception of SIB8 . 36
5.2.2.4.10 Actions upon reception of SIB9 . 37
5.2.2.5 Essential system information missing . 37
5.3 Connection control . 37
5.3.1 Introduction. 37
5.3.1.1 RRC connection control . 37
5.3.1.2 AS Security . 38
5.3.2 Paging . 39
5.3.2.1 General . 39
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5.3.2.2 Initiation . 39
5.3.2.3 Reception of the Paging message by the UE . 39
5.3.3 RRC connection establishment . 40
5.3.3.1 General . 40
5.3.3.2 Initiation . 41
5.3.3.3 Actions related to transmission of RRCSetupRequest mes sa ge . 41
5.3.3.4 Reception of the RRCSetup by the UE . 41
5.3.3.5 Reception of the RRCReject by the UE . 43
5.3.3.6 Cell re-selection or cell selection while T390, T300 or T302 is running (UE in RRC_IDLE) . 43
5.3.3.7 T300 expiry . 43
5.3.3.8 Abortion of RRC connection establishment . 44
5.3.4 Initial AS security activation . 44
5.3.4.1 General . 44
5.3.4.2 Initiation . 44
5.3.4.3 Reception of the SecurityModeCommand by the UE . 44
5.3.5 RRC reconfiguration . 45
5.3.5.1 General . 45
5.3.5.2 Initiation . 46
5.3.5.3 Reception of an RRCReconfiguration by the UE . 46
5.3.5.4 Secondary cell group release . 49
5.3.5.5 Cell Group configuration . 49
5.3.5.5.1 General . 49
5.3.5.5.2 Reconfiguration with sync . 50
5.3.5.5.3 RLC bearer release . 51
5.3.5.5.4 RLC bearer addition/modification . 51
5.3.5.5.5 MAC entity configuration . 51
5.3.5.5.6 RLF Timers & Constants configuration . 52
5.3.5.5.7 SpCell Configuration . 52
5.3.5.5.8 SCell Release . 53
5.3.5.5.9 SCell Addition/Modification . 53
5.3.5.6 Radio Bearer configuration . 53
5.3.5.6.1 General . 53
5.3.5.6.2 SRB release . 54
5.3.5.6.3 SRB addition/modification . 54
5.3.5.6.4 DRB release . 55
5.3.5.6.5 DRB addition/modification . 56
5.3.5.7 AS Security key update . 58
5.3.5.8 Reconfiguration failure . 59
5.3.5.8.1 Void . 59
5.3.5.8.2 Inability to comply with RRCReconfiguration . 59
5.3.5.8.3 T304 expiry (Reconfiguration with sync Failure) . 60
5.3.5.9 Other configuration . 60
5.3.5.10 MR-DC release . 61
5.3.5.11 Full configuration . 61
5.3.6 Counter check . 62
5.3.6.1 General . 62
5.3.6.2 Initiation . 62
5.3.6.3 Reception of the CounterCheck message by the UE . 62
5.3.7 RRC connection re-establishment . 63
5.3.7.1 General . 63
5.3.7.2 Initiation . 64
5.3.7.3 Actions following cell selection while T311 is running . 64
5.3.7.4 Actions related to transmission of RRCReestablishmentRequest message . 65
5.3.7.5 Reception of the RRCReestablishment by the UE . 66
5.3.7.6 T311 expiry . 66
5.3.7.7 T301 expiry or selected cell no longer suitable . 66
5.3.7.8 Reception of the RRCSetup by the UE . 67
5.3.8 RRC connection release . 67
5.3.8.1 General . 67
5.3.8.2 Initiation . 67
5.3.8.3 Reception of the RRCRelease by the UE . 67
5.3.8.4 T320 expiry . 69
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5.3.8.5 UE actions upon the expiry of DataInactivityTimer . 69
5.3.9 RRC connection release requested by upper layers . 69
5.3.9.1 General . 69
5.3.9.2 Initiation . 69
5.3.10 Radio link failure related actions . 69
5.3.10.1 Detection of physical layer problems in RRC_CONNECTED . 69
5.3.10.2 Recovery of physical layer problems . 70
5.3.10.3 Detection of radio link failure . 70
5.3.11 UE actions upon going to RRC_IDLE . 71
5.3.12 UE actions upon PUCCH/SRS release request . 71
5.3.13 RRC connection resume . 72
5.3.13.1 General . 72
5.3.13.2 Initiation . 73
5.3.13.3 Actions related to transmission of RRCResumeRequest or RRCResumeRequest1 message . 74
5.3.13.4 Reception of the RRCResume by the UE . 75
5.3.13.5 T319 expiry or Integrity check failure from lower layers while T319 is running . 76
5.3.13.6 Cell re-selection or cell selection while T390, T319 or T302 is running (UE in
RRC_INACTIVE) . 77
5.3.13.7 Reception of the RRCSetup by the UE . 77
5.3.13.8 RNA update. 77
5.3.13.9 Reception of the RRCRelease by the UE . 77
5.3.13.10 Reception of the RRCReject by the UE . 77
5.3.13.11 Inability to comply with RRCResume . 77
5.3.13.12 Inter RAT cell reselection . 78
5.3.14 Unified Access Control . 78
5.3.14.1 General . 78
5.3.14.2 Initiation . 78
5.3.14.3 Void. 80
5.3.14.4 T302, T390 expiry or stop (Barring alleviation) . 80
5.3.14.5 Access barring check. 80
5.3.15 RRC connection reject . 81
5.3.15.1 Initiation . 81
5.3.15.2 Reception of the RRCReject by the UE . 81
5.4 Inter-RAT mobility. 81
5.4.1 Introduction. 81
5.4.2 Handover to NR . 82
5.4.2.1 General . 82
5.4.2.2 Initiation . 82
5.4.2.3 Reception of the RRCReconfiguration by the UE . 82
5.4.3 Mobility from NR . 83
5.4.3.1 General . 83
5.4.3.2 Initiation . 83
5.4.3.3 Reception of the MobilityFromNRCommand by the UE. 83
5.4.3.4 Successful completion of the mobility from NR . 83
5.4.3.5 Mobility from NR failure . 84
5.5 Measurements . 84
5.5.1 Introduction. 84
5.5.2 Measurement configuration . 86
5.5.2.1 General . 86
5.5.2.2 Measurement identity removal . 87
5.5.2.3 Measurement identity addition/modification . 88
5.5.2.4 Measurement object removal . 88
5.5.2.5 Measurement object addition/modification . 89
5.5.2.6 Reporting configuration removal . 90
5.5.2.7 Reporting configuration addition/modification . 90
5.5.2.8 Quantity configuration . 90
5.5.2.9 Measurement gap configuration . 91
5.5.2.10 Reference signal measurement timing configuration . 92
5.5.2.11 Measurement gap sharing configuration . 92
5.5.3 Performing measurements . 93
5.5.3.1 General . 93
5.5.3.2 Layer 3 filtering . 96
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5.5.3.3 Derivation of cell measurement results . 96
5.5.3.3a Derivation of layer 3 beam filtered measurement . 97
5.5.4 Measurement report triggering . 97
5.5.4.1 General . 97
5.5.4.2 Event A1 (Serving becomes better than threshold) . 100
5.5.4.3 Event A2 (Serving becomes worse than threshold) . 101
5.5.4.4 Event A3 (Neighbour becomes offset better than SpCell) . 101
5.5.4.5 Event A4 (Neighbour becomes better than threshold) . 102
5.5.4.6 Event A5 (SpCell becomes worse than threshold1 and neighbour becomes better than
threshold2) . 102
5.5.4.7 Event A6 (Neighbour becomes offset better than SCell) . 103
5.5.4.8 Event B1 (Inter RAT neighbour becomes better than threshold) . 104
5.5.4.9 Event B2 (PCell becomes worse than threshold1 and inter RAT neighbour becomes better than
threshold2) . 104
5.5.5 Measurement reporting . 105
5.5.5.1 General . 105
5.5.5.2 Reporting of beam measurement information . 111
5.5.5.3 Sorting of cell measurement results . 111
5.5.6 Location measurement indication . 112
5.5.6.1 General . 112
5.5.6.2 Initiation . 112
5.5.6.3 Actions related to transmission of LocationMeasurementIndication message . 113
5.6 UE capabilities . 113
5.6.1 UE capability transfer . 113
5.6.1.1 General . 113
5.6.1.2 Initiation . 113
5.6.1.3 Reception of the UECapabilityEnquiry by the UE . 113
5.6.1.4 Setting band combinations, feature set combinations and feature sets supported by the UE . 114
5.6.1.5 Void. 116
5.7 Other . 116
5.7.1 DL information transfer . 116
5.7.1.1 General . 116
5.7.1.2 Initiation . 116
5.7.1.3 Reception of the DLInformationTransfer by the UE . 116
5.7.2 UL information transfer . 117
5.7.2.1 General . 117
5.7.2.2 Initiation . 117
5.7.2.3 Actions related to transmission of ULInformationTransfer message . 117
5.7.2.4 Failure to deliver ULInformationTransfer message . 117
5.7.2a UL information transfer for MR-DC . 118
5.7.2a.1 General . 118
5.7.2a.2 Initiation . 118
5.7.2a.3 Actions related to transmission of ULInformationTransferMRDC message. 118
5.7.3 SCG failure information . 118
5.7.3.1 General . 118
5.7.3.2 Initiation . 119
5.7.3.3 Failure type determination for (NG)EN-DC . 119
5.7.3.4 Setting the contents of MeasResultSCG-Failure . 119
5.7.3.5 Actions related to transmission of SCGFailureInformation message . 120
5.7.3a EUTRA SCG failure information . 122
5.7.3a.1 General . 122
5.7.3a.2 Initiation . 122
5.7.3a.3 Actions related to transmission of SCGFailureInformationEUTRA message . 122
5.7.4 UE Assistance Information . 123
5.7.4.1 General . 123
5.7.4.2 Initiation . 123
5.7.4.3 Actions related to transmission of UEAssistanceInformation message . 123
5.7.5 Failure information . 125
5.7.5.1 General . 125
5.7.5.2 Initiation . 125
5.7.5.3 Actions related to transmission of FailureInformation message . 125
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6 Protocol data units, formats and parameters (ASN.1) . 126
6.1 General . 126
6.1.1 Introduction. 126
6.1.2 Need codes and conditions for optional downlink fields . 126
6.1.3 General rules . 129
6.2 RRC messages . 129
6.2.1 General message structure . 129
– NR-RRC-Definitions . 129
– BCCH-BCH-Message . 129
– BCCH-DL-SCH-Message . 130
– DL-CCCH-Message . 130
– DL-DCCH-Message . 131
– PCCH-Message . 131
– UL-CCCH-Message . 132
– UL-CCCH1-Message . 132
– UL-DCCH-Message . 133
6.2.2 Message definitions . 134
– CounterCheck . 134
– CounterCheckResponse . 135
– DLInformationTransfer .
...