A reservation based multiple access scheme for a future Universal Mobile Telecommunications System

A future Universal Mobile Telecommunications System (UMTS), encompasses the concept of an air-interface that is able to deliver a variety of services to the mobile user, in the full compliment of environments. The RACE ATDMA project is engaged in a research and development programme to design, develop and evaluate an advanced time division multiple access (ATDMA) implementation of a UMTS system. Central to the realisation of this UMTS system is the multiple access scheme, that must efficiently multiplex channels supporting the range of services onto the air-interface, in each of the three cell types, whilst making optimum use of the allocated spectrum. The author presents a reservation based multiple access scheme to meet the requirements of UMTS, supported by an ATDMA air-interface. This multiple access scheme has become known within the RACE ATDMA project as PRMA++.