An adaptive QoS provisioning distributed call admission control using fuzzy logic control

Faced with limited radio spectrum and increased demand for broadband multimedia services in an advanced wireless network, it is becoming important to carefully manipulate handoff calls as well as new calls. In particular, there is a need for well designed call admission control (CAC) schemes that enable one to provide guaranteed QoS while efficiently utilizing the scarce radio spectrum. There have been CAC methods called distributed call admission control (DCAC) which take into consideration the traffic pattern in its adjacent cells, in addition to that in the cell where a new call request is made. However, DCAC tends to be conservative in QoS provisioning to the point that it excessively restricts access of new calls. We propose an adaptive algorithm named fuzzy logic controller for DCAC (FDCAC) which is an adaptive version of DCAC. We show by the simulation that it is possible to manage radio spectrum more flexibly than DCAC while guaranteeing the required QoS. The performance of the proposed algorithm in terms of new call blocking probability, handoff dropping probability, and channel utilization is analyzed and compared with that of previously known algorithm