Wireless connectivity touches almost every aspect of our daily lives, and LTE has delivered the ubiquitous high‐speed wireless broadband experience for us. This has unlocked the potential of mobile video and the mobile innovation that rides on those networks that we interact with every day. Lyft, Uber, Snapchat, Venmo, Square, Instagram … these are companies that simply would not exist without LTE. In addition to new innovations, global leaders such as Facebook, Alphabet, Amazon, and Netflix adapted their businesses to benefit from mobile broadband and their growth exploded!

As a result, mobile data use keeps growing, and there seems to be no end for consumer demand for more. Additionally, the need for more sophisticated mobile broadband services as well as new industries and users adopting the power of mobile broadband will push the limit on LTE technology creating a need for the next generation of mobile technology – 5G.

The next‐generation of wireless technology, 5G, will not only enhance and improve the services we enjoy today, but will also transform entire industries, from agriculture to transportation and manufacturing to become more capable, efficient, and intelligent. In other words, the evolution toward 5G is a key component in the digital transformation of almost every industry as well as of society. As such, 5G is an integral component of our continued Un‐Carrier journey into the future.

Although the promise and vision of 5G is well described, the 5G system behind it is somewhat covered in a veil of mystery. This book explaining the new 5G system from an end‐to‐end perspective, from vision and business motivation to spectrum considerations and then the technology from Radio to Core Network and service architecture demystifies what the 5G system is about. I would like to thank the authors for doing an excellent job in translating this complex topic into a book, and I hope it will serve as a useful tool for anyone wanting to understand what 5G really is all about.

Karri Kuoppamaki

Vice President

Network Technology

Development and Strategy

T‐Mobile USA