Wireless technology is a truly revolutionary paradigm shift enabling multimedia communications between people & devices from any location. It also underpins exciting applications such as sensor networks smart homes telemedicine & automated highways. This book provides a comprehensive introduction to the underlying theory design techniques & analytical tools of wireless communications focusing primarily on the core principles of wireless system design. The book begins with an overview of wireless systems & standards. The characteristics of the wireless channel are then described including their fundamental capacity limits. Various modulation coding & signal processing schemes are then discussed in detail including state-of-the-art adaptive modulation multicarrier spread spectrum & multiple antenna techniques. The concluding chapters deal with multiuser communications cellular system design & ad-hoc network design. Design insights & tradeoffs are emphasized throughout the book. It contains many worked examples over 200 figures almost 300 homework exercises over 700 references & is an ideal textbook for students. The book is also a valuable reference for engineers in the wireless industry.