h at least two trees are planted for each one used for paper production. The UMTS Network and Radio Access Technology: Air Interface Techniques for Future Mobile Systems Jonathan P. Castro Copyright © 2001 John Wiley & Sons Ltd Print ISBN 0-471-81375-3 Online ISBN 0-470-84172-9 My family for they endurance, and to my friends and colleagues for their understanding; because while putting together this book I stole too many precious moments from them. To all the 3GPP contributors for their dedication to make the UMTS specifications a reality, without whom some of the contents of this book would not have been possible. The UMTS Network and Radio Access Technology: Air Interface Techniques for Future Mobile Systems Jonathan P. Castro Copyright © 2001 John Wiley & Sons Ltd Print ISBN 0-471-81375-3 Online ISBN 0-470-84172-9 Acknowledgements It is impossible to acknowledge every one who had contributed in some way to the con- ception and realization of this book. Nonetheless, to the best of my ability I shall at- tempt to do SO. I would thus thank Mark Hammond from John Wiley, who encouraged me to go ahead and undertake the idea of writing this book; and who also patiently mo- tivated me to go forward when time was not on my side to complete the manuscript. I would also like to thank Mark's team, Sarah Hinton and Kirsten Evans for making all the practical arrangements to produce the book. Special thanks also to Lorna O'Brien who took the files to the finish. My gratitude goes also to Orange Communications SA for providing a practical and stimulating environment to deploy 2G and prepare for 3G mobile networks. In particu- lar I would like to thank the Orange UMTS Engineering team, who devoted extra time from their demanding tasks to join me in the 3G project to conceive a complete UMTS network. I am especially would like to be grateful to those in NSS and BSS Engineering for supporting my technical activities while I was writing this book and to those in Ra- dio Planning for being there, to consolidate ideas and test assu