5G System Overview

2024-07-12 18:14| 来源: 网络整理| 查看: 265

Coordinated by Alain Sultan, MCC.

Introduction

The Fifth Generation of Mobile Telephony, or 5G, or 5GS, is the system defined by 3GPP from Release 15, functionally frozen in June 2018 and fully specified by September 2019.

3GPP defines not only the air interface but also all the protocols and network interfaces that enable the entire mobile system: call and session control, mobility management, service provisioning, etc. Thanks to this approach 3GPP networks can operate in an inter-vendor and inter-operator context.

5G is defined in several phases. Release 15 specifies 5G phase 1, which introduces a new radio transmission technique and other key concepts such as an industry-grade reliability, an extended modularity, or a faster response time.

All previous generations have been designed to be used by an ever wider audience, 5G is pushing out further – ready for use by all industry sectors and for time critical applications, such as autonomous driving.

To offer these capacities, and more generally to improve the user experience, 5G makes use of a set of dedicated technologies, such as "Network Function Virtualization" and "Slicing" to increase the modularity, "EDGE computing" for faster response time, Non-Terrestrial Networks (NTN) / Satellite Communications for ubiquitous coverage, etc.

The road to a fifth generation

3GPP plays a major part in the approximate once-every-decade generational progression since the first phase of mobile standards in the 1980s. Each generation has harvested improvements throughout the system, measured in 3GPP Releases – with the groups having recently starting progress on Rel-18 specifications.

As the name suggests, 3GPP started work in 1998 on the third generation of mobile, using techniques and an evolutionary path that could be embraced by all regions. This Global convergence towards the 3GPP specifications has allowed fantastic market growth and an increasing level of assurance that broadband cellular - and now the internet-of-everything - can rely on a stable and future looking standardization platform.

From an array of mobile systems for early generations, all operators are now offering 3GPP systems, with LTE (4G) delivered by over 800 operators, with 150 of them already offering 5G to their users (Source: GSAcom.com).

5G services

5G improves on the 4G services over several axis:

Enhanced Mobile Broadband (eMBB): Higher data-rates are specified. For the downlink, up to 50 Mbps are offered for outdoor and 1 Gbps for indoor (5GLAN), with half of these values available for the uplink. A number of case studies have been under consideration, amongst them is aviation – where eMBB is helping deliver a bitrate of 1,2 Gbps to an airborne flight. Critical Communications (CC) and Ultra Reliable and Low Latency Communications (URLLC): In some contexts, extremely high reliability is expected. For instance, for remote control of process automation, a reliability of 99,9999% is expected, with a user experienced data rate up to 100 Mbps and an end-to-end latency of 50 ms. This is provided in particular through the Edge Computing capability. Massive Internet of Things (mIoT). Several scenarios require the 5G system to support very high traffic densities of devices. The Massive Internet of Things requirements include the operational aspects that apply to the wide range of IoT devices and services anticipated in the 5G timeframe. Flexible network operations. These are a set of specificities offered by the 5G system, as detailed in the following sections. It covers aspects such as network slicing, network capability exposure, scalability, and diverse mobility, security, efficient content delivery, and migration and interworking.

More information on these axis is provided in:

Release 15 Description; Summary of Rel-15 Work Items (TR 21.915) Service requirements for the 5G system (TS 22.261) NR and NG-RAN Overall description; Stage-2 (TS 38.300).

This diversity of requirements, associated to the different categories of usage described above, enables the 5G system (5GS) to be useful to a new set of markets aka. "verticals", including: automotive, rail & maritime communications; transport and logistics; discrete automation; electricity distribution; public Safety; health and wellness; smart cities; media and entertainment.

In addition to the new 5G-specific services, the 5G system supports almost all the 4G LTE ones [1 – 9] and mobility between a 5G core network and a 4G core network (EPC) is supported, with minimum impact on the user experience.

Overall architecture

Schematically, the 5G system uses the same elements as the previous generations: a User Equipment (UE), itself composed of a Mobile Station and a USIM, the Radio Access Network (NG-RAN) and the Core Network (5GC), as shown in the figure below.

【本文地址】

公司简介

联系我们