Improved CAC Scheme for WiMAX with Adaptive Bandwidth Reservation and Degradation Policy
In wireless networks, packet scheduling and Call Admission Control (CAC) play vital to ensure Quality of Service (QoS) provided to users. A single scheduling algorithm cannot guarantee all the QoS without the support of a suitable CAC and vice versa. In this paper, CAC mechanism is investigated in detail in context of IEEE 802.16 networks. The paper proposes a CAC algorithm that reserves bandwidth for both handoff and new calls. This avoids excessive blocking and starvation of new calls in the network. It also introduces QoS degradation strategy to increase number of admitted calls. Simulation results shows improvement of proposed scheme over new call bounding and fractional guard channel schemes in terms of number of admitted calls and new call blocking rate.