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.

Public safety networks provide highly robust communication systems which can address the specific needs of emergency services. This has fostered the need for public safety standards -- such as TETRA and P25 -- that provide a set of features not supported in commercial cellular systems. This book provides an in-depth analysis for adopting LTE (Long Term Evolution, the 4G 3GPP radio technology) as the technology of choice, to provide mission-critical communication services.

Written by four industry professionals, LTE for Public Safety explains how LTE can be used as technology enabler for Public Safety networks. It provides an in-depth analysis on how LTE can be used by the emergency responders for their own dedicated mission-critical network and the specialized features that are needed in LTE for providing robust and mission-critical communications amongst first responders. These include features such as group call communication and proximity services, also referred to as LTE Direct or Device to Device communication and discovery. It also provides a basic overview of the technology and some of the most important services available in LTE, providing also a justification why LTE was adopted for future Public Safety networks.

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 markets. It also aims to educate people who are interested to understand how proximity services are supported in LTE. It is written in such a way that it can be understood by both technical and nontechnical personnel with just introductory knowledge in wireless communication.

Foreword xi

About the Authors xiii

Preface xv

Acknowledgments xvii

Introduction xix

Terminology xxi

1 Introduction to LTE/SAE 1

1.1 Role of 3GPP 1

1.2 History of LTE 3

1.3 Drivers for LTE 5

1.4 EPS compared to GPRS and UMTS 6

1.5 Spectrum Considerations 7

1.6 Network Architecture 9

1.6.1 Radio Access Network and Core Network 9

1.6.2 Architecture Principles 9

1.6.3 Non-roaming Architecture 10

1.6.4 Roaming Architectures 11

1.6.5 Description of Functional Entities 12

1.6.6 Session Management 17

1.6.7 Policy and Charging Control 19

1.6.8 Interfaces and Protocols in EPS 21

1.6.9 Mobility Management 26

1.6.10 Intra E-UTRAN Handover 30

1.6.11 Security 31

1.6.12 Charging 34

1.7 IP Multimedia Subsystem 38

1.7.1 Summary of Reference Points and Protocols 40

1.8 Voice and SMS in LTE 41

1.8.1 Voice 41

1.8.2 Short Message Service 42

1.9 Interworking with 2G/3G Networks 43

1.9.1 Overview 43

1.9.2 Interworking with Legacy Networks 43

1.9.3 Functional Description 43

1.10 Interworking with Non-3GPP Access Networks 44

1.10.1 Summary of Reference Points and Protocols 47

1.11 Network Sharing 48

1.11.1 UE-Based Network Selection 49

1.11.2 RAN-Based Network Selection 49

1.12 Multimedia Broadcast Multicast Service 50

1.12.1 Principles 50

1.12.2 Description of Functional Entities 51

1.12.3 MBMS Enhancements 52

1.12.4 MBSFN and MBMS Radio Channels 53

1.13 Terms and Definitions 54

1.13.1 Roaming 54

1.13.2 Circuit-Switched and Packet-Switched Networks 55

1.13.3 Access Stratum and Non-Access Stratum 55

References 56

2 Regulatory Features 59

2.1 Emergency Calls 59

2.1.1 Overview 59

2.1.2 Requirements 59

2.1.3 Emergency Call Architecture 60

2.1.4 PSAP Callback 68

2.1.5 Emergency Numbers 68

2.1.6 Non Voice Emergency Services 69

2.1.7 Automated Emergency Calls 69

2.2 Public Warning System 71

2.3 Lawful Interception 72

2.3.1 Principles 72

2.3.2 Lawful Interception for EPS 74

2.4 Enhanced Multimedia Priority Services 74

References 76

3 LTE for Public Safety Networks 77

3.1 Why LTE for Public Safety Networks? 77

3.2 What are Public Safety Networks? 78

3.3 LTE meets Demands of Public Safety Networks 79

3.4 Wide Range of LTE Devices for Public Safety 80

3.5 Standalone versus Shared Deployments 81

3.6 Interworking 83

3.6.1 Device Aspects 83

3.6.2 Network Aspects 83

References 83

4 Proximity Services 85

4.1 Introduction to Proximity Services 85

4.1.1 Proximity Services Overview 85

4.1.2 ProSe Communication 86

4.1.3 ProSe Discovery 88

4.1.4 ProSe for Public Safety 88

4.2 Proximity Services Architectures 90

4.2.1 Non-roaming Architecture 90

4.2.2 Inter-PLMN Architecture 91

4.2.3 Roaming Architecture 91

4.2.4 Description of Functional Entities 93

4.2.5 Interfaces and Protocols 97

4.3 Synchronization 104

4.3.1 LTE Primary and Secondary Synchronization Signals 106

4.3.2 LTE D2D Synchronization 107

4.4 Service Authorization 108

4.5 ProSe Direct Discovery 109

4.5.1 ProSe Direct Discovery Models 110

4.5.2 ProSe Direct Discovery Modes 110

4.5.3 Direct Discovery Procedure for Model A 111

4.5.4 Radio Aspects and Physical Layer Design 112

4.5.5 Radio Resource Allocation for Direct Discovery 112