An adaptive threshold-based call admission strategy for wireless networks

More and more accurate traffic management mechanisms are necessary in wireless networks of the immediate future, when a minimum quality of service (QoS) level has to be guaranteed to the mobile users. To this aim, we propose a call admission mechanism based on the guard channel policy and, in order to lower the handover drop probability, we consider this mechanism distributed: the admission threshold of a cell is a function of the number of active users in the adjacent cells. Call admission is based on a MINBLOCK approach, whose target is to minimize the new-call block probability, maintaining the handover drop probability below a given threshold. A Markov-based analytical model is introduced to calculate the parameters of the guard channel mechanism and to compare the performance of the proposed mechanism with that of a pure guard channel one, which uses local information only.