LTE for Public Safety

Rainer Liebhart, Devaki Chandramouli, Curt Wong, Jürgen Merkel

• Publisher: Wiley
• Year: 2015
• Print ISBN: 9781118829868
• eBook ISBN: 9781118829837
• Edition: 1
• Topic: Technology & Engineering
• Subtopic: Mobile & Wireless Communications
• Index: Technology & Engineering

The aim of the book is to educate government agencies, operators, vendors and other regulatory institutions how LTE can be deployed to serve public safety market and offer regulatory / public safety features. It is written in such a way that it can be understood by both technical and non-technical personnel with just introductory knowledge in wireless communication. Some sections and chapters about public safety services offered by LTE network are intended to be understood by anyone with no knowledge in wireless communication.

1
Introduction to LTE/SAE

1.1 Role of 3GPP

The 3rd Generation Partnership Project (in short 3GPP) is a joint international standardization initiative between North American (Alliance for Telecommunications Industry Solutions (ATIS)), European (European Telecommunications Standards Institute (ETSI)), and Asian organizations (Association of Radio Industries and Businesses (ARIB) and Telecommunication Technology Committee (TTC) in Japan, Telecommunications Technology Association (TTA) in Korea and China Communication Standards Association (CCSA) in China) that was originally established in December 1998. The participating organizations are also called organizational partners. Scope of 3GPP was to specify a new worldwide mobile radio system (the Global System for Mobile Communications (GSM) was a European initiative while Code Division Multiple Access (CDMA) was initiated in North America, both are not compatible with each other) based on the evolved GSM techniques General Packet Radio Service (GPRS)/EDGE. This activity has led to the standardization of the third-generation Universal Mobile Telecommunications System (UMTS), which consists of Wideband Code Division Multiple Access (WCDMA) as radio technology and a core network supporting both circuit-based voice calls and packet-based data services. UMTS was meant as a universal standard that allows subscribers to use their UMTS-capable mobile phones and subscriptions worldwide through roaming (for an explanation of the term “roaming,” see Section 1.13.1) agreements between mobile operators. UMTS is a big success story with around 1.4 billion WCDMA subscriptions deployed until now.

But 3GPP did not stop work after UMTS, in the following years enhancements of UMTS like High-Speed Packet Access (HSPA)/HSPA+, new services such as Multicast/Broadcast delivery, Location services, and the IP Multimedia Subsystem (IMS) were introduced. Long-Term Evolution (LTE) with a new Orthogonal Frequency-Division Multiplexing (OFDM)-based radio technology and an All-IP core network architecture is the newest development of 3GPP.

3GPP is organized in different working groups (see Figure 1.1) that are responsible for different parts of the 3GPP system. The Radio Access Network (RAN) groups define the radio parts of the UMTS/LTE system, i.e. the physical layer, and radio protocols. The GSM/EDGE Radio Access Networks (GERAN) groups work specifically on the maintenance and development of GSM/EDGE access technologies. The System Architecture (SA) and Core/Terminal (CT) groups specify all parts of the overall system (e.g., architecture, security, charging) and all non-radio protocols (between the mobile device and network, within the network and between networks). A new working group SA6 will be operational from January 2015 onwards to standardize a Mission Critical Push To Talk (MCPTT) application in 3GPP. For details regarding MCPTT, please refer to Chapter 5.

Figure 1.1 3GPP organizational structure

3GPP follows a phased approach; working output is delivered as a set of Technical Specifications (TS) in so-called System Releases. Technical Specifications contain normative requirements that have to be implemented by chipset, device, and network equipment vendors. Interim results of ongoing work in 3GPP are usually captured in non-normative Technical Reports (TR). Test specifications are also created by 3GPP (mainly test cases for User Equipment (UE) to network communication). It has to be noted that 3GPP defines only functions and protocols, how these functions are implemented in concrete network nodes or whether some functions are implemented in the same node is up to the network vendor. One basic design principle in 3GPP's standardization process is backward compatibility of new features with existing ones. This ensures that new features can be introduced in one network without the need to upgrade all interconnected networks or all other nodes within this network at the same time.

Table 1.1 provides a brief overview of the official release dates and milestones of the 3GPP releases up to Release 12.

Table 1.1 3GPP milestones up to Release 12

Release	Date	Main content
Phases 1 and 2	1992 and 1995	Basic GSM functions
Release 96, 97, 98, 99	1996, 1997, 1998, 1999	GPRS, HSCSD, EDGE, UMTS
Release 4	2001	MSC server split architecture
Release 5	2002	HSDPA, IMS
Release 6	2004	HSUPA, MBMS, Push to Talk over Cellular (PoC)
Release 7	2007	HSPA, EDGE evolution
Release 8	2008	LTE/SAE
Release 9	2009	LTE/SAE enhancements, Public Warning System (PWS), IMS emergency sessions over LTE/HSPA
Release 10	2011	LTE Advanced Local IP Access (LIPA) Selective IP Traffic Offload (SIPTO)
Release 11	2012	Heterogeneous Network (HetNet) Support Coordinated Multipoint Operation (CoMP)
Release 12	2014	Public Safety Machine type communication HSPA/LTE carrier aggregation

For more information on the history and structure of 3GPP, visit the official 3GPP site at http://www.3gpp.org/about-3gpp/about-3gpp.

1.2 History of LTE

Main drivers for evolution of mobile networks are usually higher bandwidth on the air interface and better spectral efficiency (i.e., the information rate transmitted over a given bandwidth). After improving these key factors for WCDMA over several years, which led to the specification of HSPA and its evolution HSPA+, the 3GPP standardization forum, in 2004, started evaluating a new radio technology as successor for WCDMA. Objectives for starting this work were higher peak data rates (>100 Mbit/s in Downlink and >50 Mbit/s in Uplink) and lower latency besides other improvements. This work is formed under the name LTE. As the search for a more appealing name/acronym had no result, LTE is now used as the radio interface name in most official publications. Inside 3GPP the newly developed radio access network is called Evolved UMTS Radio Access Network (E-UTRAN) to indicate the evolution path from GERAN (GSM/GPRS/EDGE) second-generation networks (2G) to UTRAN (WCDMA/HSPA) third-generation networks (3G), and finally to E-UTRAN (LTE) fourth-generation networks (4G). It has to be noted that LTE initially did not fulfill International Telecommunication Union's (ITU) International Mobile Telecommunication (IMT) Advanced requirement...

Table of contents

• Cover
• Title Page
• Copyright
• Table of Contents
• Foreword
• About the Authors
• Preface
• Acknowledgments
• Introduction
• Terminology
• Chapter 1: Introduction to LTE/SAE
• Chapter 2: Regulatory Features
• Chapter 3: LTE for Public Safety Networks
• Chapter 4: Proximity Services
• Chapter 5: Group Communication Over LTE
• Chapter 6: Summary and Outlook
• Appendix A
• Index
• End User License Agreement