An improved mobility model for 2G and 3G cellular systems

This paper presents an improved mobility model for vehicle-borne terminals that offers a tool to compare simulations with realistic urban/suburban traffic conditions. The original mobility model considers arbitrary street patterns and realistic terminal movements in urban and suburban environments. It models the behaviour of the mobile users by a limited number of statistical parameters that can be easily derived from a city map and observation of traffic. The novel extension covers the important case that a car stops at crossroads. The probability for such event is an input parameter. The model describes the stop-and-go behaviour of vehicle-borne terminals, which is crucial for the evaluation of statistics of soft and softer handover in third-generation wireless networks. Since the street-canyon propagation has been identified as the dominant propagation mechanism in urban areas, the soft or softer handover probability is very high at crossroads. Thus, it does make a difference if the mobile users are stopping at crossroads for several tens of seconds while having soft handover connection, or if they just drive through these areas. Specifically, we apply the mobility model to a scenario in Vienna, Austria, and simulate the dwell time and the handover rate of a typical cellular system.