CONTENTS
This course provides a thorough overview of the Next-Generation Radio Access Network (NG-RAN) which is part of the 3GPP 5G System. The focus is on Stand-Alone (SA) operation but also Non-Stand Alone (NSA) NR is outlined.
The course starts with a brief introduction to the 5G System, followed by a discussion of aspects of the new radio interface and the nodes, interfaces and procedures in the NG-RAN. The course also describes various RAN – core option and dual connectivity options as well as some NG-RAN implementations such as C-RAN, O-RAN (from O-RAN Alliance) and IAB (Integrated Access and Backhaul).
PREREQUISITES
Knowledge of LTE/4G is required. Basic knowledge of the overall 5G System is recommended. Good 5G background knowledge is provided e.g. by Apis’ 5G System Overview course.
5G System Overview
- 5G System introduction, new Network Functions and Service Based Architecture
- E-UTRAN and NG-RAN elements: gNB, eNB, ng-eNB, en-gNB
- Non-Stand Alone (NSA) and Stand-Alone (SA) deployment options
- PDU Sessions and QoS flows
New Radio (NR) Fundamentals
- NR frequency bands, cell bandwidth, carrier aggregation, millimetre waves
- OFDM NR numerologies, frame and slot structure
- Differences between NR and E-UTRA
Non Stand-Alone NR with EPC
- Architecture for NSA NR
- E-UTRA – NR Dual Connectivity (EN-DC)
- Radio Bearers and CN Connections
- Handling of control plane and user plane
- The Xn interface
Stand-Alone NR with 5GC
- Architecture for SA NR
- NR – NR Dual Connectivity (NR-DC)
- Radio Bearers and CN Connections
- Handling of control plane and user plane
NG-RAN Protocols
- Overview of NG-RAN interfaces and protocols
- N2/N3/NG interfaces and NGAP protocol functions
- Xn interface and XnAP protocol functions
- RRC, SDAP, PDCP, RLC and MAC
NR Uu Channel Architecture
- Overview of the radio interface protocol stack
- Layer 2 protocols: SDAP, PDCP, RLC, MAC
- RLC Channels, Logical Channels, Transport Channels and Physical Channels
RRC and RRC States
- RRC Overview
- RRC States
- Behavior of Network and UE in IDLE, CONNECTED and INACTIVE states
- RAN Notification Areas
C-RAN – Centralized RAN
- Reasons for C-RAN
- Architecture options: gNB Central Unit and Distributed Unit
- gNB-CU Control Plane and User Plane separation
- F1-C, F1-U interfaces
- F1AP – F1 Application Protocol
- E1 interface
- E1AP – E1 Application Protocol
O-RAN Architecture
- Reasons for O-RAN
- Relation to 3GPP specifications
- O-RAN Architecture and Interfaces (A1, E2, O1, O2)
- Non-RT vs Neal-RT RAN Intelligent Controller (RIC)
Integrated Access and Backhaul (IAB)
- IAB Architecture: IAB-donor and IAB-node
- Bandwidth Adaptation Protocol (BAP)
Interworking with LTE/EPS
- Some interworking scenarios and issues between 5G and 4G
- Handover traffic case