ETSI TR 121 915 V15.0.0 (2019-10)

ETSI TR 121 915 V15.0.0 (2019-10)






TECHNICAL REPORT
Digital cellular telecommunications system (Phase 2+) (GSM);
Universal Mobile Telecommunications System (UMTS);
LTE;
5G;
Release description;
Release 15
(3GPP TR 21.915 version 15.0.0 Release 15)

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3GPP TR 21.915 version 15.0.0 Release 15 1 ETSI TR 121 915 V15.0.0 (2019-10)



Reference
DTR/TSGS-0021915vf00
Keywords
5G,GSM,LTE,UMTS
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3GPP TR 21.915 version 15.0.0 Release 15 2 ETSI TR 121 915 V15.0.0 (2019-10)
Intellectual Property Rights
Essential patents
IPRs essential or potentially essential to normative deliverables may have been declared to ETSI. The information
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"must" and "must not" are NOT allowed in ETSI deliverables except when used in direct citation.
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3GPP TR 21.915 version 15.0.0 Release 15 3 ETSI TR 121 915 V15.0.0 (2019-10)
Contents
Intellectual Property Rights . 2
Legal Notice . 2
Modal verbs terminology . 2
Foreword . 7
Introduction . 7
1 Scope . 8
2 References . 8
3 Definitions of terms, symbols and abbreviations . 8
3.1 Terms . 8
3.2 Symbols . 8
3.3 Abbreviations . 8
4 Rel-15 Executive Summary . 9
5 The 5G System (5GS) - Phase 1 . 9
5.1 Work organisation for 5GS . 9
5.2 The 5GS service aspects . 9
5.3 Overview of the 5GS architecture . 10
5.3.1 Introduction. 11
5.3.2 The NSA versus SA architecture . 11
5.3.3 Overview of the Core Network . 12
5.3.4 Overview of the Access Network . 13
5.3.5 References for 5GS Stage 2 . 13
5.5 One step deeper into the 5GS . 14
5.5.1 Functional split between Radio and Core . 14
5.5.2 The 5G Core Network. 15
5.5.2.1 Main NFs . 15
5.5.2.2 Specificities of the 5G Core Network and associated NFs . 16
5.5.2.2.1 Local hosting of services and Edge Computing . 16
5.5.2.2.2 Network slicing . 16
5.5.2.2.3 Unified access control . 17
5.5.2.2.4 Support of 3GPP and non-3GPP access . 17
5.5.2.2.5 Policy framework and QoS support . 17
5.5.2.2.6 Network capability exposure . 18
5.5.2.2.7 Other specific services . 18
5.5.2.2.8 Other 5G specificities . 18
5.5.2.3 CN protocols . 18
5.5.3 The 5G Access Network . 20
5.5.3.1 Introduction . 20
5.5.3.2 Overview of the AN Control Plane . 21
5.5.3.3 Overview of the AN User Plane . 22
5.5.3.4 The higher layers of the AN . 22
5.5.3.4.1 Layer 2 related aspects: MAC, RLC, PDCP user plane, PCP control plane, and SDAP . 22
5.5.3.4.2 RRC related aspects . 23
5.5.3.5 The Access Network interfaces . 23
5.5.3.5.1 Overview . 23
5.5.3.5.2 The Xn and X2 interfaces . 23
5.5.3.5.3 The NG and S1 interfaces . 24
5.5.3.5.4 The F1 interface . 25
5.5.4 Radio Physical layer aspects . 25
5.5.4.1 Numerologies, waveform and frame structure . 25
5.5.4.2 Physical Channels and Signals in NR . 26
5.5.4.3 Initial access and mobility . 27
5.5.4.4 MIMO aspects . 29
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5.5.4.5 PDCCH and PDSCH . 30
5.5.4.6 PUCCH and PUSCH . 31
5.5.4.7 Scheduling/HARQ . 32
5.5.4.8 Carrier Aggregation, Bandwidth Parts, and LTE/NR dual connectivity . 33
5.5.4.9 NR-LTE co-existence. 33
5.5.4.10 Supplementary Downlink . 33
5.5.4.11 Supplementary Uplink . 33
5.5.4.12 UL TPC . 34
5.5.5 Frequency aspects . 34
5.6 Other 5G aspects . 36
5.6.1 5G AN connected to 4G AN: NSA and EDCE5 . 36
5.6.1.1 Overview . 36
5.6.1.2 CN impacts: EPC enhancements to support 5G New Radio via Dual Connectivity (EDCE5) . 36
5.6.1.3 AN impacts: NSA radio protocol architecture . 38
5.6.1.3.1 Control Plane . 38
5.6.1.3.2 User Plane . 38
5.6.2 LTE connectivity to 5G-CN (4G AN with 5G CN) . 39
5.6.3 Security aspects of the 5G System - Phase 1 . 40
5.6.4 Charging and OAM aspects of 5G System - Phase 1 . 43
5.6.4.1 Data Charging in 5G System Architecture Phase 1 . 43
5.6.4.2 Other 5G System Charging aspects . 44
6 Critical Communications . 45
6.1 EPC support for E-UTRAN Ultra Reliable Low Latency Communication . 45
6.2 Highly Reliable Low Latency Communication for LTE . 45
7 Machine-Type of Communications (MTC) and Internet of T hings (IoT ) . 49
7.1 Improvements of Machine-Type of Communications (MTC) and Internet of Things (IoT) . 49
7.2 Further enhancements for Extended Coverage GSM for support of Cellular Internet of Things . 51
7.2.1 Introduction. 51
7.2.2 Energy Efficient Paging Reception with EC Paging Indication channel . 51
7.2.3 Deferred System Information Acquisition in EC operation and for PEO . 52
7.3 Even further enhanced MTC for LTE . 53
7.3.1 Support for new use cases . 53
7.3.2 Reduced latency . 53
7.3.3 Reduced UE power consumption . 54
7.3.4 Increased spectral efficiency . 54
7.3.5 Improved access control . 55
7.4 Other MTC related work . 55
74.1 AT Commands for CIoT-Ext . 55
74.2 Battery Efficient Security for very low Throughput MTC Devices . 55
8 Vehicle-to-Everything Communications (V2X) Improvements . 57
8.1 Enhancement of 3GPP support for V2X scenarios . 57
8.2 Enhancements on LTE-based V2X Services . 57
9 Improvements of Mission Critical (MC) . 59
9.1 Enhancements to MCPTT . 59
9.2 Enhancements to MC Data . 60
9.3 Enhancements to MC Video . 62
9.4 Other Mission Critical Enhancements . 62
9.4.1 MC Security Enhancements . 62
9.4.2 MBMS usage for MC communication services . 63
10 Features related to WLAN and unlicensed spectrum . 64
10.1 WLAN direct discovery . 64
10.2 Voice services over WLAN. 65
10.3 Unlicensed Spectrum Offloading System . 65
10.4 Enhancements to LTE operation in unlicensed spectrum . 66
10.5 Other functionalities related to WLAN and unlicensed spectrum . 67
11 Other new features. 68
11.1 Mobile Communication System for Railways . 68
11.2 Northbound APIs related features . 69
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3GPP TR 21.915 version 15.0.0 Release 15 5 ETSI TR 121 915 V15.0.0 (2019-10)
11.2.1 Common API Framework for 3GPP Northbound APIs . 69
11.2.2 Northbound APIs for SCEF – SCS/AS Interworking . 71
12 System enhancements. 72
12.1 Control plane - user plane separation . 72
12.1.1 Separation of CP and UP for Split Option 2 of NR . 72
12.1.2 Management Enhancement for EPC Control and User Plane Separation (CUPS) . 73
12.2 Quality of Experience (QoE) related Features. 74
12.3 Security-related improvements . 75
12.4 Virtual Reality (VR), TV, Codec and multimedia-related improvements . 75
12.4.1 Test Methodologies for the Evaluation of Perceived Listening Quality in Immersive Audio Systems . 75
12.4.2 Addition of HDR to TV Video Profiles . 76
12.4.3 Virtual Reality Profiles for Streaming Media . 76
12.4.4 FEC and ROHC Activation for GCSE over MBMS . 78
12.4.5 Media Handling Aspects of 5G Conversational Services . 78
12.5 Codec and multimedia-related improvements . 79
12.5.1 Receive acoustic output test in the presence of background noise . 79
12.5.2 Server and Network Assisted DASH for 3GPP Multimedia Services . 79
12.5.3 SAND for MBMS . 80
12.5.4 Framework for Live Uplink Streaming . 81
12.5.5 Further video enhancements for LTE . 82
12.5.6 Speech quality with ambient noise . 82
12.6 Active Antenna System (AAS) . 83
12.6.1 Architecture and interfaces . 83
12.6.2 OTA requirements . 84
12.7 OAM improvements . 85
12.8 Other enhancements . 87
12.8.1 Simplified HS-SCCH for UMTS . 87
12.8.2 Increased number of E-UTRAN data bearers . 89
12.8.3 Increasing the number of EPS bearers . 90
12.8.4 Enhancement of background data transfer . 90
12.8.5 Enhanced VoLTE performance . 90
12.8.6 DL interference mitigation for UMTS . 91
12.8.7 Enhanced Calling Name Service . 92
12.8.8 PS Data Off Phase 2. 93
13 LTE improvements . 94
13.1 Further enhancements to Coordinated Multi-Point (CoMP) Operation for LTE . 94
13.2 Enhancements for high capacity stationary wireless link and introduction of 1024 QAM for LTE DL . 95
13.3 UE requirements for network-based CRS interference mitigation for LTE . 96
13.4 Bluetooth®/WLAN measurement collection in LTE Minimization of Drive Tests (MDT) . 97
13.5 UL data compression in LTE . 98
13.6 UE Positioning Accuracy Enhancements for LTE . 98
13.7 UE requirements for LTE DL 8Rx antenna ports . 99
13.8 Shortened TTI and processing time for LTE . 100
13.8.1 Short processing time for 1 ms TTI . 100
13.8.2 Short TTI . 101
13.9 Enhanced LTE Support for Aerial Vehicles . 105
13.10 Enhancing LTE CA Utilization . 106
14 OAM improvements . 106
14.1 Other 5G System Charging aspects . 106
14.1.1 Service Based Interface for 5G Charging . 106
14.1.2 Charging for IMS over 5G System Architecture Phase 1 . 107
14.1.3 SMS Charging in 5G System Architecture Phase 1 . 107
14.2 Management and virtualization aspects of 5G networks and network slicing . 108
15 Work Items for which no summary is needed . 110
Annex A: Structure of 5GS Rel-15 3GPP work.
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