ETSI TR 138 912 V15.0.0 (2018-09)

ETSI TR 138 912 V15.0.0 (2018-09)






TECHNICAL REPORT
5G;
Study on New Radio (NR) access technology
(3GPP TR 38.912 version 15.0.0 Release 15)

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3GPP TR 38.912 version 15.0.0 Release 15 1 ETSI TR 138 912 V15.0.0 (2018-09)



Reference
RTR/TSGR-0038912vf00
Keywords
5G
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3GPP TR 38.912 version 15.0.0 Release 15 2 ETSI TR 138 912 V15.0.0 (2018-09)
Intellectual Property Rights
Essential patents
IPRs essential or potentially essential to normative deliverables may have been declared to ETSI. The information
pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found
in ETSI SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in
respect of ETSI standards", which is available from the ETSI Secretariat. Latest updates are available on the ETSI Web
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Foreword
This Technical Report (TR) has been produced by ETSI 3rd Generation Partnership Project (3GPP).
The present document may refer to technical specifications or reports using their 3GPP identities, UMTS identities or
GSM identities. These should be interpreted as being references to the corresponding ETSI deliverables.
The cross reference between GSM, UMTS, 3GPP and ETSI identities can be found under
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Modal verbs terminology
In the present document "should", "should not", "may", "need not", "will", "will not", "can" and "cannot" are to be
interpreted as described in clause 3.2 of the ETSI Drafting Rules (Verbal forms for the expression of provisions).
"must" and "must not" are NOT allowed in ETSI deliverables except when used in direct citation.
ETSI

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3GPP TR 38.912 version 15.0.0 Release 15 3 ETSI TR 138 912 V15.0.0 (2018-09)
Contents
Intellectual Property Rights . 2
Foreword . 2
Modal verbs terminology . 2
Foreword . 7
1 Scope . 8
2 References . 8
3 Definitions, symbols and abbreviations . 9
3.1 Definitions . 9
3.2 Symbols . 9
3.3 Abbreviations . 9
4 Introduction . 10
5 Deployment scenario . 10
6 Forward compatibility . 11
7 Radio interface protocol architecture for next generation radio . 12
7.1 User plane . 12
7.1.1 User plane protocol stack for NR . 12
7.1.2 Bearer types for Dual Connectivity between LTE and NR . 12
7.2 Control plane . 13
7.2.1 Control plane protocol stack for NR . 13
7.2.2 Control plane architecture for Dual Connectivity between LTE and NR . 14
7.2.2.1 UE capability coordination between LTE and NR . 15
8 Physical layer for next generation radio . 16
8.1 Numerologies and frame structure . 16
8.2 Downlink transmission scheme . 18
8.2.1 Basic transmission scheme . 18
8.2.1.1 Modulation scheme . 18
8.2.1.2 Physical layer channel . 18
8.2.1.2.1 Physical resource multiplexing . 18
8.2.1.2.2 Data channel . 18
8.2.1.2.3 Control channel . 18
8.2.1.3 Waveform. 19
8.2.1.4 Multiple access scheme . 19
8.2.1.5 Channel coding . 19
8.2.1.5.1 LDPC . 20
8.2.1.5.2 Polar coding . 21
8.2.1.6 Multi-antenna scheme . 21
8.2.1.6.1 Beam management . 21
8.2.1.6.2 MIMO schemes . 23
8.2.1.6.3 CSI measurement and reporting . 24
8.2.1.6.4 Reference signal related to multi-antenna scheme. 27
8.2.1.6.4.1 CSI-RS . 27
8.2.1.6.4.2 DM-RS . 28
8.2.1.6.4.3 Phase-tracking RS (PT-RS) . 29
8.2.1.6.5 Quasi-colocation (QCL) . 29
8.2.1.6.6 Network coordination and advanced receiver . 29
8.2.2 Physical layer procedure . 30
8.2.2.1 Scheduling . 30
8.2.2.2 HARQ . 30
8.2.2.3 Initial access and mobility . 30
8.2.2.3.1 Synchronization signal and DL broadcast signal/channel structure . 30
8.2.2.3.2 Mobility . 31
8.2.2.3.3 Paging . 32
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3GPP TR 38.912 version 15.0.0 Release 15 4 ETSI TR 138 912 V15.0.0 (2018-09)
8.3 Uplink transmission scheme . 32
8.3.1 Basic transmission scheme . 32
8.3.1.1 Modulation scheme . 32
8.3.1.2 Physical layer channel . 32
8.3.1.2.1 Data channel . 32
8.3.1.2.2 Control channel . 32
8.3.1.3 Waveform. 33
8.3.1.4 Multiple access scheme . 34
8.3.1.5 Channel coding . 34
8.3.1.5.1 LDPC . 34
8.3.1.5.2 Polar coding . 34
8.3.1.6 Multi-antenna scheme . 34
8.3.1.6.1 Beam management and CSI acquisition . 34
8.3.1.6.2 MIMO schemes . 34
8.3.1.6.3 Reference signal related to multi-antenna scheme. 35
8.3.1.6.3.1 SRS . 36
8.3.1.6.3.2 PT-RS . 36
8.3.2 Physical channel procedure. 36
8.3.2.1 Random access procedure . 36
8.3.2.1.1 Preamble . 36
8.3.2.1.2 Procedure . 37
8.3.2.2 Scheduling . 38
8.3.2.3 Power control . 38
8.3.2.4 HARQ . 38
8.4 Duplexing . 38
8.5 LTE-NR Co-existence . 38
8.6 Carrier Aggregation / Dual Connectivity . 39
9 Layer 2 and RRC for next generation radio . 40
9.1 Overview of Layer 2 functions . 40
9.2 MAC Sublayer . 42
9.3 RLC Sublayer . 42
9.4 PDCP Sublayer . 42
9.5 New AS sublayer . 43
9.6 Overview of Layer 2 data flow . 43
9.7 Numerologies and TTI durations . 43
9.8 RRC . 44
9.8.1 Functions . 44
9.8.2 UE states and state transitions. 44
9.8.2.1 RAN-based notification are management . 45
9.8.3 System information handling . 46
9.8.3.1 Dual Connectivity between LTE and NR. 47
9.8.4 Measurements . 47
9.8.4.1 Dual Connectivity between LTE and NR. 47
9.8.5 Access control . 47
9.8.6 UE capability retrieval framework . 47
10 Architecture for next generation RAN . 48
10.1 RAN-CN functional split . 48
10.2 Overall architecture . 49
10.3 Interfaces . 49
10.3.1 RAN-CN interface . 49
10.3.1.1 General principles . 49
10.3.1.2 NG Interface Functions . 50
10.3.1.3 NG Interface Architecture . 50
10.3.1.4 NG Control Plane . 50
10.3.1.5 NG User Plane . 51
10.3.2 RAN internal interface . 51
10.3.2.1 Xn Interface. 51
10.3.2.1.1 General principles . 52
10.3.2.1.2 Xn Interface Functions . 52
10.3.2.1.3 Xn Control Plane . 52
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3GPP TR 38.912 version 15.0.0 Release 15 5 ETSI TR 138 912 V15.0.0 (2018-09)
10.3.2.1.4 Xn User Plane . 53
11 QoS . 53
11.1 QoS architecture in NR and NextGen Core . 53
11.2 Dual Connectivity between LTE and NR via EPC . 55
12 Support for Network Slicing . 55
13 Key higher layer and network procedures . 55
13.1 Initial access . 55
13.1.1 Cell selection . 55
13.1.2 Random access procedure . 56
13.2 Mobility . 56
13.2.1 Intra-RAT . 56
13.2.1.1 UE based mobility . 56
13.2.1.1.1 Cell reselection . 56
13.2.1.1.2 Paging . 57
13.2.1.2 Network controlled mobility . 57
13.2.2 Inter-RAT . 58
13.2.3 Mobility related to Dual Connectivity between LTE and NR . 60
13.3 Dual Connectivity between NR and LTE . 60
13.3.1 General . 60
13.3.2 Option 3/3a/3x . 61
13.3.2.1 General principles for Xx interface . 61
13.3.2.2 Architectural aspects . 61
13.3.2.3 Procedural aspects . 61
13.3.3 Option 4/4a . 61
13.3.3.1 Architectural aspects . 61
13.3.3.2 Procedural aspects . 62
13.3.4 Option 7/7a/7x . 62
13.3.4.1 Architectural aspects . 62
13.3.4.2 Procedural aspects . 63
13.4 PDU Session Management . 63
13.4.1 Session Setup . 63
13.4.2 Session Modification . 64
13.4.3 Session Release . 64
14 Radio transmission/reception . 65
14.1 Potential spectrum . 65
14.2 Co-existence consideration . 66
14.3 UE/BS RF feasibility . 66
14.3.1 Common requirements for UE and BS . 66
14.3.1.1 Subcarrier spacing . 67
14.3.1.2 Maximum channel bandwidth . 67
14.3.1.3 Flexible channel bandwidth . 67
14.3.1.4 UE transmission bandwidth configuration adaptation . 67
14.3.1.5 Spectrum Utilization . 68
14.3.2 UE RF requirements . 68
14.3.2.1 Wide frequency range of up to 52.6 GHz handling .
...