ABSTRACT
Current standardization activities of 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) working groups show that hierarchical UMTS networks influenced by GSM and ISDN history are changing towards decentralized and distributed network architectures based on IP principles. Equipment manufacturers submitted various proposals for UMTS R6. Subsequently 3GPP ordered a feasibility study and requested an evaluation of the different architecture proposals with regard to performance. In this paper we present a simulation modeling approach, which provides an environment for the easy assessment of different evolution scenarios of the UMTS architecture with regard to signalling performance. We apply the presented simulation concept to a case study, which compares a new distributed radio access network (DRAN) architecture for UMTS and the current Universal Terrestrial Radio Access Network (UTRAN). For both RANs under study a Central Processing Unit (CPU) capacity planning is performed aiming at optimization of the signalling performance. Furthermore the developed simulation concept also allows for an estimation of the allocated CPU capacity for the RANs under consideration.
