Traffic modeling of a hierarchical cellular system in the presence of heterogeneous calls

A hierarchical cellular system that supports two classes of mobility for users generating low and high speed calls is considered. An analytical model for a non-prioritized scheme without macrocell to microcell handoffs is presented. Numerical performance determined through the definition of a multidimensional Markov chain in the case of cut-off priority, show blocking and forced termination probability for each type of call. These results are reported for cases where the state explosion problem remains manageable. A more general study taking into account macrocell to microcell handoffs is conducted by simulation.