5G

An Introduction to the 5th Generation Mobile Networks

Ulrich Trick

• Publisher: De Gruyter Oldenbourg
• Year: 2021
• Print ISBN: 9783110724370
• eBook ISBN: 9783110724622
• Edition: 1
• Topic: Technology & Engineering
• Subtopic: Information Technology
• Index: Technology & Engineering

5G mobile networks use new concepts and technologies to provide current and future applications from high bit-rate smartphones to highly available Car-to-X and IoT applications. But not only technology is an issue. Also, the environmental impact is under discussion. These topics are presented here in a well-founded introduction, with the focus on innovative concepts and technologies, including standardization.

1 Evolution of Mobile Networks

With 5G, the development of mobile networks has entered a new phase. So far, the focus of such networks has been on the provision of communication services for people. In the case of 4G, multimedia data services such as video streaming with a smartphone, tablet, or generally a computer as the end device are the most important. With previous versions, the further back the more, the main focus was on telephony. Now, with 5G, the multimedia applications consumed by mobile users fall under traditional services, although supported very high bit rates. Compared to previous versions, at least before 4G, the support of M2M (Machine to Machine communications) and IoT (Internet of Things) comes more into focus, but still with the corresponding 4G air interface, now with a high connection density compared to the beginnings with 4G. A completely new feature of 5G is the support of services in system and safety-critical application areas such as Smart Grid for intelligent energy supply networks and autonomous driving with very high demands on latency, response times, and system and service availability.

As shown in Figure 1.1, the introduction of digital mobile communications networks in the 1990s began with the 2nd generation – the 1st generation still used analog technology – based on GSM technology (Global System for Mobile Communications). Parallel to the GSM solution standardized in Europe by 3GPP (3rd Generation Partnership Project), the IS-54 (Interim Standard) and the IS-136, and finally, the IS-95 standard (cdmaOne) were developed in North America [187].

Fig. 1.1: Evolution of mobile networks [54]

In many networks, the 2G solution consisted and still consists of a circuit-switched (CS) core network (CN) GSM and the associated access network (AN). With respect to the ease of use of IP over a mobile phone network, the CN was extended by a packet switching part, the GPRS (General Packet Radio Service). In parallel, the AN was migrated to be able to transport IP at moderate bit rates with EDGE technology (Enhanced Data Rates for GSM Evolution). This led to the current name GERAN (GSM/EDGE Radio Access Network).

In the early 2000s, the next step was the introduction of the 3rd generation, also known as UMTS (Universal Mobile Telecommunications System). Using W-CDMA (Wideband-Code Division Multiple Access) technology resulted in a much more powerful AN, UTRAN (Universal Terrestrial Radio Access Network), with significantly higher bit rates, but still with the CN based on GSM and GPRS. In the context of 3G, bit rates increased successively in the AN under the keyword HSPA (High Speed Packet Access).

There was also a parallel development in North America for 3G. The 3GPP partner organization 3GPP2 (3rd Generation Partnership Project 2) [186] standardized the 3G cdma2000 solution with several successive versions [187].

The next step, the 4th generation, brought a new, high bit-rate access network technology based solely on IP, E-UTRAN (Evolved-UTRAN), under the name LTE (Long Term Evolution). An LTE system provides telephony with VoIP (Voice over IP), here called VoLTE (Voice over LTE). Because of the real-time capability required for IP traffic, a new, real-time-capable IP core called EPC (Evolved Packet Core) became necessary. The IMS (IP Multimedia Subsystem), also shown in Figure 1.1 for the 3G evolution, is essential for signaling in VoLTE, and more generally, for Multimedia over IP services. The IMS with SIP (Session Initiation Protocol) plays an important role not only for 3G but also for 4G and 5G systems to provide real-time communication services.

The 4th generation of mobile networks is in operation today, alongside the parallel or integrated previous versions. It delivers high bit rates based on LTE, LTE-Advanced, and LTE-Advanced Pro access network technology and already has support for M2M and IoT with a separate Air Interface variant. In addition, the topic of virtualization with the use of only virtual network functions realized by software based on standard hardware has already started here [54].

The 5th generation of mobile networks is currently being launched. It provides not only a new powerful RAN (Radio Access Network) technology, called NR (New Radio), for very high bit rates, very low delays (latency), and very high connection densities but also a new, highly modular, and flexible 5G core with Service Based Architecture (SBA) and Network Slicing. The underlying technologies used are NFV (Network Functions Virtualization) and SDN (Software Defined Networking) in cloud environments. But this is not all. Without changing the core network, 5G also enables not only NR, non-3GPP WLAN, and 4G access but also fixed lines via, for example, PON (Passive Optical Network) or DSL (Digital Subscriber Line) and even direct access to a 5G network via a satellite connection. A 5G system can thus implement FMC (Fixed Mobile Convergence) with only one core network technology. For this reason, 5G can no longer be called a mobile network. If a 5G system is deployed and used in this general way, it is a new generation converged network.

The following sections and chapters deal with this evolution and to some extent revolutionary development. There is a good balance between introducing the basic ideas, concepts, and techniques, and more detailed considerations. We start with the basics, connection concepts, and routing principles. On this basis, the 2G/3G evolution is explained, and the NGN concept (Next Generation Networks), including VoIP and SIP, is covered. Chapter 2 describes concepts, protocols, and techniques of 3rd and 4th generation mobile networks. It includes IMS and VoLTE. Chapter 3 introduces the future networks standardized by the ITU. With NFV, Cloud, and Edge Computing, as well as SDN, they are already defining essential building blocks for 5G, anticipating 5G systems. From chapter 4 to chapter 10, there is a systematic introduction to 5G with more in-depth coverage wherever useful and necessary. The starting point is not new technical possibilities but use cases and new usage areas. It results in the requirements. These have been and still are the basis for standardization, especially in ITU and 3GPP, and regulation in individual countries. The requirements result in necessary network functions, which, according to selected design principles, lead to a 5G system and a 5G network architecture. For a more detailed analysis, a distinction can be made here between the access network and the core network. The knowledge gained in this process then leads to an overall view of a 5G system, including the interaction with 4G. Finally, concerning the technology, the security in a 5G system is considered.

Introducing a new network generation must also be considered from the perspective of the impact on the environment. Therefore, we address the topics of non-ionizing radiation due to radio transmission and energy consumption. Finally, we take a look into the future, first at the further development of 5G and then at an already planned 6th generation. That makes sense, as Figure 1.1 shows that a new mobile network generation is introduced approximately every ten years and that research, standardization, and development of the next network generation is already taking place parallel to the generation currently in operation.

1.1 Connection Concepts and Routing Principles

The technical development and, thus, the migration of the telecommunication networks and especially of the mobile networks, can be well characterized by the connection concepts and routing principles applied in each case.

As an introduction to this topic, Figure 1.2 shows an example of a connection setup for a telephone call between two subscribers (Sub) A and B in a telecommuni...

Table of contents

• Title Page
• Copyright
• Contents
• 1 Evolution of Mobile Networks
• 2 3G/4G Mobile Networks and NGN (Next Generation Networks)
• 3 Future Networks
• 4 5G Use Cases and Requirements
• 5 5G Standardization and Regulation
• 6 5G Networks at a Glance
• 7 5G Access Networks
• 8 5G Core Network
• 9 5G System
• 10 5G and Security
• 11 5G and Environment
• 12 Future Developments
• Abbreviations
• Index