This book first provides some background material of wireless communications, traffic modeling and traffic engineering techniques. It then gives high level descriptions of CDMA2000/UMTS and WLAN systems, discusses some of the issues that engineers face when designing these systems, and provides innovative solutions for these issues. The last chapter provides some descriptions of upcoming features, e.g. IP multimedia subsystems, multimedia broadcast/multicast services and Push-to-Talk over Cellular (PoC) for 3G networks. This book is very useful for professors and system designers who do not have prior experience designing practical 3G wireless systems. The level of presentation is suitable for graduate students and practical engineers with some prior undergraduate level courses of digital communications and networking. Learning is facilitated by the problems included at the end of each chapter.