3GPP TS 38 300 V 1 6 4 0 ( 20 20 - 12 ) Technical Specification 3rd Generation Partnership Project; Technical Specification Group Radio Access Network ; NR ; NR and NG - RAN Overall Description ; Stage 2 ( Release 1 6 ) The present document has been developed within the 3 rd Generation Partnership Project (3GPP TM ) and may be further elaborated for the purposes of 3GPP. The present document has not been subject to any approval process by the 3GPP Organizational Partners and shall not be implemented. This Specification is provided for future development work within 3GPP only. The Organizational Partners accept no liability for any use of this Spe cification. Specifications and Reports for implementation of the 3GPP TM system should be obtained via the 3GPP Organizational Partners' Publications Offices. 3GPP 3GPP TS 38.300 V16.4.0 (2020 - 12) 2 Release 16 3GPP Postal address 3GPP support office address 650 Route des Lucioles - Sophia Antipolis Valbonne - FRANCE Tel.: +33 4 92 94 42 00 Fax: +33 4 93 65 47 16 Internet http://www.3gpp.org Copyright Notification No part may be reproduced except as authorized by written permission. The copyright and the foregoing restriction extend to reproduction in all media. © 20 20 , 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). All rights reserved. UMTS™ is a Trade Mark of ETSI registered for the benefit of its members 3GPP™ is a Trade Mark of ETSI registered for the b enefit of its Members and of the 3GPP Organizational Partners LTE™ is a Trade Mark of ETSI registered for the benefit of its Members and of the 3GPP Organizational Partners GSM® and the GSM logo are registered and owned by the GSM Association 3GPP 3GPP TS 38.300 V16.4.0 (2020 - 12) 3 Release 16 Contents Foreword ................................ ................................ ................................ ................................ ...................... 9 1 Scope ................................ ................................ ................................ ................................ ................ 10 2 References ................................ ................................ ................................ ................................ ........ 10 3 Definitions and Abbreviations ................................ ................................ ................................ ........... 11 3.1 Abbreviations ................................ ................................ ................................ ................................ ............. 11 3.2 Definitions ................................ ................................ ................................ ................................ ................. 14 4 Overall Architecture and Functional Split ................................ ................................ .......................... 15 4.1 Overall Architecture ................................ ................................ ................................ ................................ ... 15 4.2 Functional Split ................................ ................................ ................................ ................................ .......... 16 4.3 Network Interfaces ................................ ................................ ................................ ................................ ..... 18 4.3.1 NG Interface ................................ ................................ ................................ ................................ ......... 18 4.3.1.1 NG User Plane ................................ ................................ ................................ ................................ 18 4.3.1.2 NG Control Plane ................................ ................................ ................................ ............................ 19 4.3.2 Xn Interface ................................ ................................ ................................ ................................ .......... 19 4.3.2 .1 Xn User Plane ................................ ................................ ................................ ................................ 19 4.3.2 .2 Xn Control Plane ................................ ................................ ................................ ............................. 20 4.4 Radio Protocol Architecture ................................ ................................ ................................ ....................... 21 4.4.1 User Plane ................................ ................................ ................................ ................................ ............ 21 4.4.2 Control Plane ................................ ................................ ................................ ................................ ........ 21 4.5 Multi - Radio Dual Connectivity ................................ ................................ ................................ .................. 21 4.6 Radio Access Network Sharing ................................ ................................ ................................ .................. 22 4.7 Integrated Access and Backhaul ................................ ................................ ................................ ................. 22 4.7.1 Architecture ................................ ................................ ................................ ................................ .......... 22 4.7.2 Protocol Stacks ................................ ................................ ................................ ................................ ..... 23 4.7.3 User - plane Aspects ................................ ................................ ................................ ............................... 25 4.7.3.1 Backhaul transport ................................ ................................ ................................ ........................... 25 4.7.3.2 Flow and Congestion Control ................................ ................................ ................................ .......... 25 4.7.3.3 Uplink Scheduling Latency ................................ ................................ ................................ .............. 26 4.7.4 Signalling procedures ................................ ................................ ................................ ............................ 26 4.7.4.1 IAB - node Integration ................................ ................................ ................................ ....................... 26 4.7.4.2 IAB - node Migration ................................ ................................ ................................ ........................ 26 4.7.4.3 Topological Redundancy ................................ ................................ ................................ ................. 26 4.7.4.4 Backhaul RLF Recovery ................................ ................................ ................................ .................. 27 4.7.4.5 OTA timing synchronization ................................ ................................ ................................ ............ 27 4.7.4.6 Inter node discovery ................................ ................................ ................................ ........................ 27 4.8 Non - Public Networks ................................ ................................ ................................ ................................ 27 5 Physical Layer ................................ ................................ ................................ ................................ .. 27 5.1 Waveform, numerology and frame structure ................................ ................................ ............................... 27 5.2 Downlink ................................ ................................ ................................ ................................ ................... 28 5.2.1 Downlink transmission scheme ................................ ................................ ................................ ............. 28 5.2.2 Physical - layer processing for physical downlink shared channel ................................ ............................ 28 5.2.3 Physical downlink control channels ................................ ................................ ................................ ....... 29 5.2.4 Synchronization signal and PBCH block ................................ ................................ ............................... 30 5.2.5 Physical layer procedures ................................ ................................ ................................ ...................... 30 5.2.5.1 Link adaptation ................................ ................................ ................................ ............................... 30 5.2.5.2 Power Control ................................ ................................ ................................ ................................ 31 5.2.5.3 Cell search ................................ ................................ ................................ ................................ ...... 31 5.2.5.4 HARQ ................................ ................................ ................................ ................................ ............. 31 5.2.5.5 Reception of SIB1 ................................ ................................ ................................ ........................... 31 5.2.6 Downlink Reference Signals and Measurements for Positioning ................................ ............................ 31 5.3 Uplink ................................ ................................ ................................ ................................ ....................... 31 5.3.1 Uplink transmission scheme ................................ ................................ ................................ .................. 31 5.3.2 Physical - layer processing for physical uplink shared channel ................................ ................................ 32 5.3.3 Physical uplink control channel ................................ ................................ ................................ ............. 32 5.3.4 Random access ................................ ................................ ................................ ................................ ..... 33 3GPP 3GPP TS 38.300 V16.4.0 (2020 - 12) 4 Release 16 5.3.5 Physical layer procedures ................................ ................................ ................................ ...................... 34 5.3.5.1 Link adaptation ................................ ................................ ................................ ............................... 34 5.3.5.2 Uplink Power control ................................ ................................ ................................ ...................... 34 5.3.5.3 Uplink timing control ................................ ................................ ................................ ...................... 34 5.3.5.4 HARQ ................................ ................................ ................................ ................................ ............. 34 5.3.5.5 Prioritization of overlapping transmissions ................................ ................................ ....................... 34 5.3.6 Uplink Reference Signals and Measurements for Positioning ................................ ................................ 35 5.4 Carrier aggregation ................................ ................................ ................................ ................................ .... 35 5.4.1 Carrier aggregation ................................ ................................ ................................ ............................... 35 5.4.2 Supplementary Uplink ................................ ................................ ................................ .......................... 35 5.5 Transport Channels ................................ ................................ ................................ ................................ .... 35 5.6 Access to Shared Spectrum ................................ ................................ ................................ ........................ 36 5.6.1 Overview ................................ ................................ ................................ ................................ .............. 36 5.6.2 Channel Access Priority Classes ................................ ................................ ................................ ............ 37 5.7 Sidelink ................................ ................................ ................................ ................................ ..................... 37 5.7.1 General ................................ ................................ ................................ ................................ ................. 37 5.7.2 Sidelink resource allocation modes ................................ ................................ ................................ ........ 38 5.7.3 Physical sidelink channels and signals ................................ ................................ ................................ ... 38 5.7.4 Physical layer procedures for sidelink ................................ ................................ ................................ ... 38 5.7.4.1 HARQ feedback ................................ ................................ ................................ .............................. 38 5.7.4.2 Power Control ................................ ................................ ................................ ................................ 38 5.7.4.3 CSI report ................................ ................................ ................................ ................................ ....... 38 5.7.5 Physical layer measurement definition ................................ ................................ ................................ .. 38 6 Layer 2 ................................ ................................ ................................ ................................ ............. 39 6.1 Overview ................................ ................................ ................................ ................................ ................... 39 6.2 MAC Sublayer ................................ ................................ ................................ ................................ ........... 42 6.2.1 Services and Functions ................................ ................................ ................................ .......................... 42 6.2.2 Logical Channels ................................ ................................ ................................ ................................ .. 43 6.2.3 Mapping to Transport Channels ................................ ................................ ................................ ............ 43 6.2.4 HA RQ ................................ ................................ ................................ ................................ .................. 43 6.3 RLC Sublayer ................................ ................................ ................................ ................................ ............ 43 6.3.1 Transmission Modes ................................ ................................ ................................ ............................. 43 6.3.2 Services and Functions ................................ ................................ ................................ .......................... 44 6.3.3 ARQ ................................ ................................ ................................ ................................ ..................... 44 6.4 PDCP Sublayer ................................ ................................ ................................ ................................ .......... 44 6.4.1 Services and Functions ................................ ................................ ................................ .......................... 44 6.5 SDAP Sublayer ................................ ................................ ................................ ................................ .......... 45 6.6 L2 D ata Flow ................................ ................................ ................................ ................................ ............. 45 6.7 Carrier Aggregation ................................ ................................ ................................ ................................ .... 45 6.8 Dual Connectivity ................................ ................................ ................................ ................................ ...... 47 6.9 Supplementary Uplink ................................ ................................ ................................ ................................ 47 6.10 Bandwidth Adaptation ................................ ................................ ................................ ................................ 47 6.11 Backhaul Adaptation Protocol Sublayer ................................ ................................ ................................ ...... 48 6.11.1 Services and Functions ................................ ................................ ................................ .......................... 48 6.11.2 Traffic Mapping from Upper Layers to Layer - 2 ................................ ................................ ..................... 48 6.11.3 Routing and BH - RLC - channel mapping on B AP sublayer ................................ ................................ ..... 49 6.12 Multiple Transmit/Receive Point Operation ................................ ................................ ................................ 50 7 RRC ................................ ................................ ................................ ................................ ................. 50 7.1 Services and Functions ................................ ................................ ................................ ............................... 50 7.2 Protocol States ................................ ................................ ................................ ................................ ........... 51 7.3 System Information Handling ................................ ................................ ................................ ..................... 52 7.3.1 Overview ................................ ................................ ................................ ................................ .............. 52 7.3.2 Scheduling ................................ ................................ ................................ ................................ ............ 53 7.3.3 SI Modificatio n ................................ ................................ ................................ ................................ ..... 53 7.4 Access Control ................................ ................................ ................................ ................................ ........... 54 7.5 UE Capability Retrieval framework ................................ ................................ ................................ ............ 54 7.6 Transport of NAS Messages ................................ ................................ ................................ ....................... 54 7.7 Carrier Aggregation ................................ ................................ ................................ ................................ ... 54 7.8 Bandwidth Adaptation ................................ ................................ ................................ ................................ 55 7.9 UE Assistance Information ................................ ................................ ................................ ......................... 55 3GPP 3GPP TS 38.30 0 V16.4.0 (2020 - 12) 5 Release 16 7.10 Segmentation of RRC messages ................................ ................................ ................................ ................. 55 8 NG Identities ................................ ................................ ................................ ................................ .... 56 8.1 UE Identities ................................ ................................ ................................ ................................ .............. 56 8.2 Network Identities ................................ ................................ ................................ ................................ ...... 56 8.3 User Data Transport on the CN - RAN Interface ................................ ................................ ........................... 5 7 8.4 NR sidelink communication and V2X sidelink communication related identities ................................ ......... 57 9 Mobility and State Transitions ................................ ................................ ................................ .......... 58 9.1 Overview ................................ ................................ ................................ ................................ ................... 58 9.2 Intra - NR ................................ ................................ ................................ ................................ .................... 59 9.2.1 Mobility in RRC_IDLE ................................ ................................ ................................ ........................ 59 9.2.1.1 Cell Selection ................................ ................................ ................................ ................................ .. 59 9.2.1.2 Cell Reselection ................................ ................................ ................................ .............................. 59 9.2.1.3 State Transitions ................................ ................................ ................................ .............................. 60 9.2.2 Mobility in RRC_INACTIVE ................................ ................................ ................................ ............... 62 9.2.2.1 Overview ................................ ................................ ................................ ................................ ........ 62 9.2.2.2 Cell Reselection ................................ ................................ ................................ .............................. 63 9.2.2.3 RAN - Based Notification Area ................................ ................................ ................................ ......... 63 9.2.2.4 State Transitions ................................ ................................ ................................ .............................. 63 9.2.2.4.1 UE triggered transition from RRC_INACTIVE to RRC_CONNECTED ................................ ..... 63 9.2.2.4.2 Network triggered transition from RRC_INACTIVE to RRC_CONNECTED ............................. 65 9.2.2.5 RNA update ................................ ................................ ................................ ................................ .... 66 9.2.3 Mobility in RRC_CONNECTED ................................ ................................ ................................ .......... 68 9.2.3.1 Overview ................................ ................................ ................................ ................................ ........ 68 9.2.3.2 Handover ................................ ................................ ................................ ................................ ........ 70 9.2.3.2.1 C - Plane Handling ................................ ................................ ................................ ....................... 70 9.2.3.2.2 U - Plane Handling ................................ ................................ ................................ ...................... 74 9.2.3.2.3 Data Forwarding ................................ ................................ ................................ ........................ 76 9.2.3.3 Re - establishment procedure ................................ ................................ ................................ ............. 77 9.2.3.4 Conditional Handover ................................ ................................ ................................ ...................... 78 9.2.3.4.1 General ................................ ................................ ................................ ................................ ...... 78 9.2.3.4.2 C - plane handling ................................ ................................ ................................ ........................ 79 9.2.3.4.3 U - plane handling ................................ ................................ ................................ ........................ 81 9.2.3.4.4 Data Forwarding ................................ ................................ ................................ ........................ 81 9.2.4 Measurements ................................ ................................ ................................ ................................ ....... 81 9.2.5 Paging ................................ ................................ ................................ ................................ .................. 84 9.2.6 Random Access Procedure ................................ ................................ ................................ .................... 85 9.2.7 Radio Link Failure ................................ ................................ ................................ ................................ 87 9.2.8 Beam failure detection and recovery ................................ ................................ ................................ ...... 88 9.2.9 Timing Advance ................................ ................................ ................................ ................................ ... 88 9.3 Inter RAT ................................ ................................ ................................ ................................ .................. 89 9.3.1 NR - E - UTRA mobility: Intra 5GC ................................ ................................ ................................ ......... 89 9.3.1.1 Cell Reselection ................................ ................................ ................................ .............................. 89 9.3.1.2 Handover ................................ ................................ ................................ ................................ ........ 89 9.3.1.3 Measurements ................................ ................................ ................................ ................................ 89 9.3.2 NR - E - UTRA mobility: From 5GC to EPC ................................ ................................ ............................ 89 9.3.2.1 Cell Reselection ................................ ................................ ................................ .............................. 89 9.3.2.2 Handover and redirection ................................ ................................ ................................ ................. 90 9.3.2.3 Measurements ................................ ................................ ................................ ................................ 90 9.3.2.4 Data Forwarding for the Control Plane ................................ ................................ ............................. 90 9.3.2. 5 Data Forwarding for the User Plane ................................ ................................ ................................ 91 9.3.3 NR - E - UTRA mobility: From EPC to 5GC ................................ ................................ ............................ 91 9.3.3.1 Data Forwarding for the Control Plane ................................ ................................ ............................. 91 9.3.3. 2 Data Forwarding for the User Plane ................................ ................................ ................................ 92 9.3.4 NR - UTRA mobility ................................ ................................ ................................ .............................. 92 9.3.4.1 Handover with SRVCC operation ................................ ................................ ................................ .... 92 9.3.4.2 Measurements ................................ ................................ ................................ ................................ 93 9.4 Roaming and Access Restrictions ................................ ................................ ................................ ............... 93 10 Scheduling ................................ ................................ ................................ ................................ ........ 93 10.1 Basic Scheduler Operation ................................ ................................ ................................ ......................... 93 10.2 Downlink Scheduling ................................ ................................ ................................ ................................ 94 3GPP 3GPP TS 38.300 V16.4.0 (2020 - 12) 6 Release 16 10.3 Uplink Scheduling ................................ ................................ ................................ ................................ ..... 94 10.4 Measurements to Support Scheduler Operation ................................ ................................ ........................... 95 10.5 Rate Control ................................ ................................ ................................ ................................ ............... 96 10.5.1 Downlink ................................ ................................ ................................ ................................ ............. 96 10.5.2 Uplink ................................ ................................ ................................ ................................ .................. 96 10.6 Activation/Deactivation Mechanism ................................ ................................ ................................ ........... 96 10.7 E - UTRA - NR Cell Resource Coordination ................................ ................................ ................................ .. 97 10.8 Cross Carrier Scheduling ................................ ................................ ................................ ............................ 97 10.9 IAB Resource Configuration ................................ ................................ ................................ ...................... 97 11 UE Power Saving ................................ ................................ ................................ .............................. 98 12 QoS ................................ ................................ ................................ ................................ .................. 99 12.1 Overview ................................ ................................ ................................ ................................ ................... 99 12.2 Explicit Congestion Notification ................................ ................................ ................................ ............... 101 13 Security ................................ ................................ ................................ ................................ .......... 101 13.1 Overvie w and Principles ................................ ................................ ................................ ........................... 101 13.2 Security Termination Points ................................ ................................ ................................ ..................... 103 13.3 State Transitions and Mobility ................................ ................................ ................................ .................. 104 14 UE Capabilities ................................ ................................ ................................ ............................... 104 15 Self - Configuration and Self - Optimisation ................................ ................................ ....................... 104 15.1 Definitions ................................ ................................ ................................ ................................ ............... 104 15.2 Void ................................ ................................ ................................ ................................ ........................ 105 15.3 Self - configuration ................................ ................................ ................................ ................................ .... 105 15.3.1 Dynamic configuration of the NG - C interface ................................ ................................ ..................... 105 15.3.1.1 Prerequisites ................................ ................................ ................................ ................................ .. 105 15.3.1.2 SCTP initialization ................................ ................................ ................................ ........................ 105 15.3.1.3 Application layer initialization ................................ ................................ ................................ ....... 1 05 15.3.2 Dynamic Configuration of the Xn interface ................................ ................................ ......................... 105 15.3.2.1 Prerequisites ................................ ................................ ................................ ................................ .. 105 15.3.2.2 SCTP initialization ................................ ................................ ................................ ........................ 105 15.3.2.3 Application layer initialization ................................ ................................ ................................ ....... 105 15.3.3 Automatic Neighbour Cell Relation Function ................................ ................................ ...................... 106 15.3.3.1 General ................................ ................................ ................................ ................................ ......... 106 15.3.3.2 Intra - system Automatic Neighbour Cell Relation Function ................................ ............................. 107 15.3.3.3 Void ................................ ................................ ................................ ................................ .............. 107 15.3.3.4 Void ................................ ................................ ................................ ................................ .............. 107 15.3.3.5 Inter - system Automatic Neighbour Cell Relation Function ................................ ............................. 107 15.3.4 Xn - C TNL address discovery ................................ ................................ ................................ .............. 108 15 .4 Support for Energy Saving ................................ ................................ ................................ ....................... 109 15 .4.1 General ................................ ................................ ................................ ................................ ............... 109 15 .4.2 Solution de scription ................................ ................................ ................................ ............................ 109 15.4.3 O&M requirements ................................ ................................ ................................ ............................. 109 15.5 Self - optimisation ................................ ................................ ................................ ................................ ...... 110 15.5.1 Support for Mobility Load Balancing ................................ ................................ ................................ .. 110 15.5.1.1 General ................................ ................................ ................................ ................................ ......... 110 15.5.1.2 Load reporting ................................ ................................ ................................ ............................... 110 15.5.1.4 Adapting handover and/or reselection configuration ................................ ................................ ....... 110 15.5.2 Support for Mobility Robustness Optimization ................................ ................................ .................... 111 15.5.2.1 General ................................ ................................ ................................ ................................ ......... 111 15.5.2.2 Connection failure ................................ ................................ ................................ ......................... 111 15.5.2.2.1 General ................................ ................................ ................................ ................................ .... 111 15.5.2.2.2 Connection failure due to intra - system mobility ................................ ................................ ........ 111 15.5.2.2.3 Connection failure due to inter - system mobili ty ................................ ................................ ........ 112 15.5.2.3 Inter - system Unnecessary HO ................................ ................................ ................................ ........ 113 15.5.2.4 Inter - system Ping - pong ................................ ................................ ................................ .................. 114 15.5.2.5 O&M Requirements ................................ ................................ ................................ ...................... 114 15.5.3 Support for RACH Optimization ................................ ................................ ................................ ......... 114 15.5.4 UE History Information from the UE ................................ ................................ ................................ .. 114 3GPP 3GPP TS 38.300 V16.4.0 (2020 - 12) 7 Release 16 16 Vertica ls Support ................................ ................................ ................................ ............................ 115 16.1 URLLC ................................ ................................ ................................ ................................ .................... 115 16.1.1 Overview ................................ ................................ ................................ ................................ ............ 115 16.1.2 LCP Restrictions ................................ ................................ ................................ ................................ 115 16.1.3 Packet Duplication ................................ ................................ ................................ .............................. 115 16.1.4 CQI and MCS ................................ ................................ ................................ ................................ ..... 116 16.1.5 DCI formats ................................ ................................ ................................ ................................ ........ 116 16.1.6 Higher layer multi - connectivity ................................ ................................ ................................ ........... 116 16.1.6.1 Redundant user plane paths based on dual connecti vity ................................ ................................ .. 116 16.1.6.2 R edundant data transmission via single UPF and single RAN node ................................ ................ 117 16.2 IMS Voice ................................ ................................ ................................ ................................ ............... 117 16.2.0 Support for IMS voice ................................ .................