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Universal Personal Communications (UPC) establishes the new concept of personal mobility and personal numbering [1]. In the UPC environment the fixed association between terminal and user identification is removed. This establishes the basis for personal mobility. Personal communications involves providing an essentially transparent connection so that a practical range of services can be automatically provided to people on the move [2]. Both wired and wireless access can, and should be involved, with existing infrastructures forming the basis of service delivery to a person rather than to a place | Broadband Wireless Mobile 3G and Beyond. Edited by Willie W. Lu Copyright 2002 John Wiley Sons Ltd. ISBN 0-471-48661-2 2 UMTS Air Interface Introduction Universal Personal Communications UPC establishes the new concept of personal mobility and personal numbering 1 . In the UPC environment the fixed association between terminal and user identification is removed. This establishes the basis for personal mobility. Personal communications involves providing an essentially transparent connection so that a practical range of services can be automatically provided to people on the move 2 . Both wired and wireless access can and should be involved with existing infrastructures forming the basis of service delivery to a person rather than to a place. The goal of third-generation mobile systems is to provide users with world-wide coverage via handsets that have the capability to seamlessly roam between multiple networks fixed and mobile cordless and cellular across regions which currently use different technologies. This wireless and wired mobility clearly complements UPC giving the user total mobility across both types of networks. Third-generation mobile systems are one step beyond the digital cellular and cordless systems that are now into service. At the global level regarding the third-generation of mobile systems in ITU International Telecommunication Union there is already an initiative IMT-2000 3-7 settling the framework of the future telecommunication infrastructure. IMT-2000 will provide wireless access to the global telecommunication infrastructure through both satellite and terrestrial systems serving fixed and mobile users in public and private networks. It is being developed on the basis of the family of systems concept designed to be able to connect different radio transmission modules to the same core network equipment. The radio interfaces defined are based on different access technologies. The access technology not only defines how the users access the