This research works aim to design the QoS mechanisms for mobile WiMAX systems. We combine admission control, packet classifier, bandwidth allocation and packet scheduling to design the QoS simulation platform for such a WiMAX system.We also design the handover mechanism according to the general handover procedure specified by the IEEE802.16e-2005 standard. Finally, performance evaluations via simulations are conducted to assess the system performance for the network with or without handover procedures employed. It is found that the transmission quality is subject to the modulation rate change significantly in the mobile environments. The proposed Qos and handover mechanisms are shown to reduce connection blocking rate and packet dropping rate effectively to enhance WiMAX system efficiency.
Keywords：WiMAX、QoS、Bandwidth allocation mechanism、Mobile system、Handover。