Testbeds for assessing the performance of a TDMA-based radio access design for UMTS

With the successful introduction of GSM (Global System for Mobile communications) networks in many countries, attention is now turning to the development of the next, or third, generation of mobile cellular systems. The requirements for these systems are expressed in the ITU concept of FPLMTS (Future Public Land Mobile Telecommunication Systems), and the parallel ETSI concept of UMTS (Universal Mobile Telecommunications System). Key elements in the definition of third generation systems are the radio access system and the subtending radio transmission technology. A procedure for evaluating the relative merit of radio transmission technologies is being developed as one of the instruments for identifying the radio access system(s) to be standardised. The evaluation phase will typically be performed by exercising testbeds related to the radio access proposals. A TDMA-based radio access design for UMTS has been introduced. This design bases on a new functional model for relating transport and control functions and has been developed in the framework of the European RACE Advanced TDMA Mobile Access (ATDMA) project. The performance of the ATDMA design is being assessed through a complex testbed activity aimed at: (1) proving the viability and the effective interworking of a range of radio techniques; and (2) estimating the traffic capacity of the design