Development and optimisation of a statistical multiplexing mechanism for ATDMA

The paper describes the development, refinement and optimisation of a realistic packet based access mechanism for third generation mobile systems incorporating an adaptive air interface. The paper describes the multiple access scheme PRMA++, a medium access control mechanism for the RACE R2084 advanced time division multiple access system (ATDMA), and outlines the essential differences to PRMA, an access mechanism which has been identified as suitable for consideration for a future Universal Mobile Telecommunication System (UMTS). The paper illustrates the development of PRMA++ and in particular its mapping on to burst and frame structures compatible with an adaptive air interface concept as part of ATDMA. Refinement and optimisation of candidate access mechanisms within the project have been largely based on computer simulation. Some example results from a comprehensive discrete event simulator are given, illustrating the power of a simulation tool in the extraction of statistical information which may be used to optimise system performance