الفهرس 
chapter 1Only 14 pages are availabe for public view
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Abstract
one of the fundamental requirement for IEEE 802.16/WiMAX, to become a key technology for high-speed multimedia service delivery, is qos (quality of service) differentiation. although different types of qos classes have been defined by the IEEE 802.16 standard, the scheduling architecture is left to be vendor specific. in this paper, new modifications are purposed, and a detailed simulation study is performed, for different scheduling algorithms which are: RR (round robin), WRR (weighted round robin) and DRR ( deficit round robin). analysis and evaluation of the performance of each scheduler to support the different QoS classes have been performed. the simulation results show that the purposed channel aware modified DRR scheduler can provide higher service standards to support the QoS in terms of packet loss ratio and bounded delay, which is require by different types of traffic in a time varying channel.