 LTE Key Performance Optimization 4. Small Cell Enhancements in 3GPP 13. LTE Capacity Optimization 14. LTE Voice Optimization 5. Small Cell Deployment Options Monry 15. LTE Inter-Layer Mobility Optimization Public outdoor Public indoor Enterprise Residential VoLTE Micro Pico or Femto 16. Smartphone enterprise femto 6. Small Cell Products Optimization 7. Small Cell Interference Managements Time(sec) 8. Small Cell Optimization 17. Future Outlook for LTE Evolution Figure P.1 Contents of the book Preface Smartphones, tablets and laptops are the main use cases for LTE networks currently, but LTE radio will be the foundation for many new applications in the future. Internet of things, public safety, device-to-device communication, broadcast services and vehicle communication are a few examples that can take benefit of future LTE radio. The contents of the book are summarized in Figure P.1. Chapters 1-3 provide an introduc- tion to LTE in 3GPP Releases 8-13. The small cell-specific topics are discussed in Chapters 4-10 including 3GPP features, network architecture, products, interference management, opti- mization, practical learnings and unlicensed spectrum. The LTE optimization is presented in Chapters 11-16 including 3GPP evolution, performance, voice, inter-layer and smartphone optimization. Chapter 17 illustrates the outlook for further LTE evolution. Acknowledgements The editors would like to acknowledge the hard work of the contributors from Nokia Net- works, T-Mobile USA and Videotron Canada: Rajeev Agrawal, Anand Bedekar, Mihai Enescu, Amitava Ghosh, Tero Henttonen, Wang Hua, Suresh Kalyanasundaram, Jari Lindholm, Timo Lunttila, Riku Luostari, Bishwarup Mondal, Laurent Noël, Brian Olsen, Klaus Pedersen, Karri Ranta-aho, Claudio Rosa, Jari Salo, Rafael Sanchez-Mejias, Mikko Simanainen, Beatriz Soret and Benny Vejlgaard. The editors also would like to thank the following colleagues for their valuable comments and contributions: Petri Aalto, Yin-tat Peter Chiu, Bong Youl (Brian) Cho, Jeongho (Jackson) Cho, Jinho (