Scheduler Dependent Modeling of Inter-cell Interference in UMTS EUL

In this paper we analyze the performance of the UMTS Enhanced Uplink (EUL) in a network scenario, under various packet scheduling schemes. Besides the impact of the intrinsic differences of the scheduling schemes on EUL performance (which we studied in a previous paper for a single cell scenario), we are particularly interested in how the different scheduling schemes influence EUL performance through their impact on the characteristics of the intercell interference. For our analysis we use a hybrid analytical/simulation approach, originally developed for the single cell situation, and extend it to our multi cell scenario. We show that the mutual influence between neighbouring cells due to inter-cell interference is largely determined by only one or two power iteration steps, which considerably speeds up computations. Our approach takes into account both the packet-level characteristics and the flow-level dynamics due to the random user behaviour. For the considered schedulers we evaluate and compare performance measures such as the mean flow transfer time and throughput.