The performance of wireless data systems has been thoroughly studied in the context of a single base station. In this talk we examine networks with several interacting base stations, and specifically investigate the capacity impact of intra- and inter-cell mobility. We consider a dynamic setting where users come and go over time as governed by random finite-size data transfers, and explicitly allow for users to roam around over the course of their service. It may be shown that mobility tends to increase the capacity, not only in case of globally optimal scheduling, but also when each of the base stations operates according to a fair sharing policy. We further demonstrate that the capacity region for globally optimal scheduling is in general strictly larger than the stability region for a fair sharing discipline. However, if the users distribute themselves so as to maximize their individual throughputs, thus enabling some implicit coordination, then a fair sharing policy is in fact guaranteed to achieve stability whenever a globally optimal strategy is able to do so.
Note: The talk is based on joint work with Nidhi Hegde and Alexandre Proutiere (France Telecom R&D).
