Adaptive Connection Admission Control and Packet Scheduling for QoS Provisioning in Mobile WiMAX

The authors propose a connection admission control (CAC) scheme and a packet scheduling algorithm for the IEEE 802.16e-2005 standard for fixed and mobile broadband wireless access systems. CAC reserves an adaptive temporal channel bandwidth for mobile subscriber stations based on most recent requests to assure seamless handoff of connections, while the scheduler allocates physical layer slots to user packets based on the corresponding application's data rate and latency characteristics. The effectiveness of the proposed architecture is evaluated though simulations. It is shown that 1) when the system is moderately loaded, the proposed CAC performs better than a fixed guard channel scheme in terms of reducing handoff dropping and new call blocking probabilities; 2) the proposed packet scheduling scheme prioritizes real-time over non real-time traffic in accordance with the quality of service (QoS) parameters of service flows defined in the IEEE standard.