Femtocells

Prof. Simon Saunders, PhD, CEng, FIETFounding Chairman of the Femto Forum, Independent Wireless Technologist and Visiting Professor, University of Surrey. Professor Simon Saunders is an independent specialist in the technology of wireless communications, with a technical and commercial background derived from senior appointments in both industry (including Philips and Motorola) and academia (University of Surrey). He is an author of over 150 articles, books and book chapters. He has acted as a consultant to companies including BAA, BBC, O2, Ofcom, BT, ntl, Mitsubishi and British Land and was CTO of Red-M and CEO of Cellular Design Services Ltd. Simon speaks at and chairs a wide range of international conferences and training courses and has invented several novel wireless technologies. Particular expertise includes in-building wireless systems, radiowave propagation prediction, smart antenna design and mobile system analysis. He currently serves on technical advisory boards of several companies. He is the founding chairman of the Femto Forum, a Visiting Professor to the University of Surrey and is amember of the Ofcom Spectrum Advisory Board.See www.simonsaunders.com for further details. Stuart Carlaw, Vice President Mobile Wireless – ABI Research. StuartCarlawholds a program management role for ABI Research’s Wireless Practice, which includes coordinating and planning its wireless infrastructure, mobile operator, wireless handset semiconductor, short range wireless connectivity, fixed mobile convergence, femtocell, mobile device and business mobility research services. He is also lead analyst for the femtocell, fixed-mobile convergence and mobile devices research services.He brings to the task a deep understanding of the critical issues and technologies, stemming from his immersion in these markets for over a decade as both an analyst and an engineer.Prior to joining ABI Research, Stuart was a Telecommunications Technician in the British Army, and then Senior Analyst and laterWireless Research Director at IMS Research. At IMS he was the primary Bluetooth analyst, and responsible for all short range wireless research.He has been quoted and published in a variety of industry and general media, including BBC TV, BBC Radio 5, the Financial Times, the Wall Street Journal, EE Times and many more, and has spoken, moderated or participated in industry events including WiMAX World, TETRA WorldCongress, Bluetooth SIG AHM, PTTWorldCongress and Freescale Technology Forum.Stuart earned a BSc (Honours) in Physical Sciences and Business Management from De Montfort University.Dr Andrea Giustina, Vice President, Systems Engineering – Ubiquisys Ltd.Dr Giustina joined Ubiquisys in early 2006 where he heads the definition of Femtocell offers and system design. With over 15 years of experience in telecoms, he previously held management positions in Lucent Technologies in Systems Engineering and Professional Services for GPRS, WCDMA and IMS Services and was a Researcher for Telecom Italia.Dr Giustina holds a Doctor’s degree in Electronics Engineering and a Telecommunications Master, both from Politecnico di Torino, and an MBA from Bath University.Ravi Raj Bhat, Ravi Raj Bhat is an Engineering Director at Continuous Computing, managing its software R&D organisation. Ravi has published over 25 technical papers and articles in technical magazines including IEEE Communication and Electronic Design. Ravi had also co-authored a book titled, Java in Telecommunication, published by John Wiley & Sons in September 2001. Ravi holds an MBA from the Anderson School of Management at University of California, Los Angeles and BTech in Computer Engineering from National Institute of Technology, Karnataka.V. Srinivasa Rao, V. Srinivasa Rao is an Architect for Wireless & IMS Trillium Protocol Software at Continuous Computing. In this capacity, Srinivasa is responsible for conceptualising initial product architecture and design. His oversight includes all the wireless and IMS protocol software products developed by CCPU. Srinivasa has published articles in technical magazines including Electronic Design. His expertise of communications systems ranges from the end-to-end network to signalling protocol software, with a primary focus on IMS and 3G wireless.Mr Srinivasa holds an MTech in Telecommunication Systems & Engineering from the Indian Institute of Technology, Kharagpur.Rasa Siegberg, Senior Systems Engineer, Mobile & Networking Security Solutions, SafeNet Inc.Rasa Siegberg joined SafeNet in 2005 as Systems Engineer responsible for technical presales and sales support, and various aspects of product management and marketing for the company’s portfolio of embedded software security solutions.Currently Rasa provides strategic guidance; sales, product management, and marketing support for all embedded hardware and software security products at SafeNet with a special focus on new technologies within the telecom/mobile industry.He has more than 10 years of experience in telecom, semiconductor, networking and embedded security industries. Prior to joining SafeNet, Rasa worked as a Senior Consultant at Conformiq Software, and as a Product Manager at SSH Communications Security Ltd. He received his MA from Helsinki University, Finland.

• About the Authors xvForeword xixPreface xxiAcknowledgements xxiiiAbbreviations xxvList of Figures xxxvList of Tables xxxix1 Introduction to Femtocells 1Simon Saunders1.1 Introduction 11.2 Why Femtocells? The Market Context 11.3 The Nature of Mobile Broadband Demand 21.4 What is a Femtocell? 41.4.1 Femtocell Attributes 61.4.2 Femtocell Standards 71.4.3 Types of Femtocell 71.5 Applications for Femtocells 71.6 What a Femtocell is not 81.7 The Importance of ‘Zero-Touch’ 101.8 User Benefits 111.9 Operator Motivations and Economic Impact 131.10 Operator Responses 141.11 Challenges 151.12 Chapter Overview 152 Small Cell Background and Success Factors 17Simon Saunders2.1 Introduction 172.2 Small Cell Motivations 172.2.1 Cellular Principles 172.2.2 Conventional Cell Types: Why ‘Femtocells’? 182.2.3 Challenges of Achieving Indoor Coverage from Outdoor Macrocells 202.2.4 Spectrum Efficiency 212.2.5 Geometry Factors 232.2.6 The Backhaul Challenge 242.3 Other Small-Cell Systems 242.3.1 Overview 242.3.2 Picocells 242.3.3 Distributed Antenna Systems 252.3.4 Wireless Local Area Networks 272.4 The Small-Cell Landscape 282.5 Emergence of the Femtocell – Critical Success Factors 292.5.1 Mobile Data Adoption and Revenue Growth 302.5.2 Broadband Adoption 302.5.3 Connecting Four Billion Users – And Counting 312.5.4 Internet Applications 332.5.5 Fixed–Mobile Substitution 332.5.6 User Device Availability 362.5.7 Processing Power and Cost 362.6 Conclusions 373 Market Issues for Femtocells 39Stuart Carlaw3.1 Key Benefits of a Femtocell from Market Perspective 393.1.1 In-Home Coverage 393.1.2 Macro Network Capacity Gain 403.1.3 Termination Fees 403.1.4 Simplistic Handset Approach 413.1.5 Home Footprint and the Quadruple Play 413.1.6 Maximising Returns on Spectrum Investment 423.1.7 Churn Reduction – The Sticky Bundle 423.1.8 Positive Impact on Subsidisation Trends 433.1.9 Value-Added Services 433.1.10 Changing User Behaviour 433.1.11 Reducing Energy Consumption 443.2 Key Primers 443.2.1 Broadband Penetration 443.2.2 Saturation 453.2.3 Evolution in Carrier Business Model 463.2.4 Competition 473.2.5 Technical Feasibility 483.2.6 Economics 483.2.7 Limitations in Other Services 493.2.8 Carrier and Manufacturer Support 493.2.9 Consumer Demand 503.2.10 Supporting the Data Boom 503.2.11 Growing Standardisation 503.2.12 Air Interface Technology Evolution 523.3 Key Market Challenges 523.3.1 Cost Pressure 523.3.2 Intellectual Property Rights 533.3.3 Technology Issues 533.3.4 Establishing a ‘Sellable’ Proposition 543.3.5 Disconnect Between OEMs and Carriers 543.3.6 Too Much Reliance on Standards 543.3.7 Window of Opportunity 553.3.8 Developing the Ecosystem 553.4 Business Cases for Femtocells 553.4.1 Business Case Foundations 553.4.2 Exploring the Economics 573.5 Air Interface Choices 603.5.1 GSM Advantages 603.5.2 GSM Disadvantages 613.5.3 WCDMA Advantages 613.5.4 WCDMA Disadvantages 613.5.5 Conclusions 613.5.6 HSDPA, HSUPA and HSPA+ 623.6 Product Feature Sets 623.6.1 Stand-Alone 623.6.2 Broadband Gateway 633.6.3 Wi-Fi Access Point 633.6.4 TV Set-Top Box 633.6.5 Video Distribution Mechanisms 643.6.6 Segmentation 643.7 Additional Considerations 643.7.1 Enterprise Femtocells 643.7.2 Super-Femtocells and Outdoor Femtocells 653.8 Adoption Forecasts and Volumes 653.8.1 Methodology 653.8.2 Forecasts 683.9 Conclusions 704 Radio Issues for Femtocells 71Simon Saunders4.1 Introduction 714.2 Spectrum Scenarios 714.3 Propagation in Femtocell Environments 734.4 Coverage 744.5 Downlink Interference 754.6 Interference Challenges and Mitigations 794.7 Femtocell-to-Femtocell Interference 804.8 System-Level Performance 814.9 RF Specifications in WCDMA 844.10 Health and Safety Concerns 864.11 Conclusions 895 Femtocell Networks and Architectures 91Andrea Giustina5.1 Introduction 915.2 Challenges 925.3 Requirements 935.4 Femto Architectures and Interfaces 945.5 Key Architectural Choices 965.5.1 Connecting Remote Femtocells 965.5.2 Integrating the Femto Network with the Macro Network 985.5.3 Functional Split between the FAP and the FGW 1005.6 Other Important Femto Solution Aspects 1015.6.1 End-to-End Quality of Service 1025.6.2 Local Access (Data and Voice) 1035.6.3 Femtozone Services 1055.6.4 Mobility 1065.6.5 Femtocell Location 1085.6.6 Enterprise and Open Spaces 1095.7 UMTS Femtos 1105.7.1 Iuh Protocol Stacks 1105.8 CDMA 1125.9 WiMAX 1135.10 GSM 1145.11 LTE 1155.12 Conclusions 1166 Femtocell Management 117Ravi Raj Bhat and V. Srinivasa Rao6.1 Introduction 1176.2 Femtocell FCAPS Requirements 1186.2.1 Fault and Event Management 1196.2.2 Configuration Management 1196.2.3 Accounting and Administration Management 1196.2.4 Performance Management 1206.2.5 Security Management 1206.3 Broadband Forum Auto-Configuration Architecture and Framework 1206.4 Auto-Configuration Data Organisation 1216.4.1 Data Hierarchy 1216.4.2 Profiles 1236.5 CPE WAN Management Protocol Overview 1236.5.1 Protocol Stack and Operation 1246.6 FAP Service Data Model 1266.6.1 Control Object Group 1266.6.2 Configuration Object Group 1266.6.3 Monitoring Object Group 1286.6.4 Management Object Group 1296.7 DOCSIS OSS Architecture and Framework 1296.8 Conclusions 1327 Femtocell Security 133Rasa Siegberg7.1 Why is Security Important? 1337.1.1 Viewpoint: Continuity 1337.1.2 Viewpoint: (Contained) Change 1347.2 The Threat Model 1347.2.1 Threats from ‘Outsiders’ – Third Parties 1357.2.2 Threats from ‘Insiders’ – Device Owners 1357.3 Countering the Threats 1367.3.1 Radio Link Protection 1367.3.2 Protecting the (IP) Backhaul 1387.3.3 Device Integrity – Tamper Resistance 1437.4 Conclusions 1458 Femtocell Standards and Industry Groups 147Simon Saunders8.1 The Importance of Standards 1478.2 GSM 1488.3 WCDMA 1488.3.1 TSG RAN WG2 – Radio Layer 2 and Radio Layer 3 RR 1498.3.2 TSG RAN WG3 Architecture 1498.3.3 TSG RAN WG4 Radio Performance and Protocol Aspects RF Parameters and BS Conformance 1508.3.4 TSG SA WG1 – Services 1508.3.5 TSG SA WG3 – Security 1508.3.6 TSG SA WG5 Telecom Management 1518.3.7 Summary of WCDMA Standards 1518.4 TD-SCDMA 1518.5 LTE 1518.6 CDMA 1538.7 Mobile WiMAX 1558.8 The Femto Forum 1568.9 The Broadband Forum 1578.10 GSMA 1578.11 Conclusions 1579 Femtocell Regulation 159Simon Saunders9.1 Introduction 1599.2 Regulatory Benefits of Femtocells 1599.3 Spectrum Efficiency 1609.4 Economic Efficiency 1609.5 Enabling Competition 1609.6 Broadening Access to Services 1619.7 Enabling Innovation 1619.8 Environmental Goals 1619.9 Spectrum Licensing Issues 1629.10 Location 1639.11 Authentication 1639.12 Emergency Calls 1639.13 Lawful Interception and Local IP Access 1649.14 Backhaul Challenges 1659.15 Mobile Termination Rates 1659.16 Competition Concerns 1669.17 Equipment Approvals 1669.18 Examples of Femtocell Regulations 1669.19 Conclusions 16810 Femtocell Implementation Considerations 169Simon Saunders10.1 Introduction 16910.2 Signal Processing 17010.3 Location 17010.4 Frequency and Timing Control 17110.5 Protocol Implementation 17210.6 RF Implementation 17210.7 System Design and Cost 17310.8 Mobile Device Challenges and Opportunities 17510.9 Conclusions 17611 Business and Service Options for Femtocells 177Simon Saunders and Stuart Carlaw11.1 Introduction 17711.2 Ways of being a Femtocell Operator 17711.3 Femtocells for Fixed-Line Operators 18011.4 Types of Femtocell Service 18111.5 Service Examples 18211.5.1 Femtozone Services 18211.5.2 Connected Home Services 18411.6 Service Enablers 18511.6.1 Service Implementation 18611.7 Stages of Femtocell Service Introduction 18611.7.1 Stage 1 – Supporting Fixed Mobile Substitution 18711.7.2 Stage 2 – Prompting Mobile Data Uptake 18711.7.3 Stage 3 – Bringing the Mobile Phone into the Connected Home Concept 18711.7.4 Stage 4 – Taking the Connected Home into the Wider World 18711.8 Conclusions 18812 Summary: The Status and Future of Femtocells 189Simon Saunders12.1 Summary 18912.2 Potential Future Femtocell Landscape 19112.2.1 Growth of Femtocell Adoption 19112.2.2 Femtocells in Homes and Offices 19212.2.3 Femtocells in Developing and Rural Markets 19212.2.4 Femtocells Outdoors 19212.2.5 Femtocell-Only Operators 19312.2.6 Femtos Enabling Next-Generation Mobile Networks 19312.2.7 When is a Femtocell not a Femtocell? 19512.3 Concluding Remarks 195References 197Further Reading 203Appendix: A Brief Guide to Units and Spectrum 205Index 207