ns. Commun., 44(10), 1996. [22] Shannon, C.E., "Communications in the Presence of Noise," Proc. IRE, 37, 1949, 10-21. [23] Garg, V.K., Smolik, K. and Wilkes, J.E. Applications of CDMA in Wireless/Personal Communications, Prentice Hall, New Jersey, 1997. 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 THE UMTS DEVELOPMENT PLATFORM ARCHITECTURE AND DEPLOYMENT SCENARIOS The architecture at the domain and functional levels, as well as the deployment scenar- ios are presented based on the 3GPP (ETSI) specifications noted in [1,2]. The terminol- ogy and basic principles are kept for consistency with a simplified approach in some cases, and for a pragmatic representation of the subject in others. 3.1.1 The UMTS High Level System Architecture 3.1.1.1 The UMTS Domains Figure 3.1 illustrates the different UMTS domains. The identified domains imply the evolution of current or existing network infrastructures, but do not exclude new ones. The Core Network (CN) domain can evolve for example from the GSM, N-ISDN, B- ISDN, and PDN infrastructures. Network Domain Mobile Access Serving Transit Domain Equipment Network Network Network Domain Domain Domain Domain Core Network Domain User Equipment Domain Infrastructure Domain Cu : Reference point between USIM and ME Iu : Reference point between Access and Serving Network domains Uu : Reference point between User Equipment and Infrastructure domains, UMTS radio interface [Yu] = Reference point between Serving and Transit Network domains [Zu] = Reference point between Serving and Home Network domains Figure 3.1 UMTS architecture domains and reference points. The UMTS Network and Radio Access Technology The generic architecture incorporates two main domains, i.e. the user equipment domain and the infrastructure domain. The first concerns the equipment used by the user to access UMTS services having a radio interface to the infras