In order to support different types of multimedia applications, the IEEE 802.16 standard defines different service classes with their associated Quality of Service (QoS) parameters. The scheduling algorithm is the crucial point in QoS provisioning over such broadband wireless access (BWA) network and it is important that the scheduling algorithm have a multi-dimensional objective of satisfying QoS requirements of the users, maximizing system utilization and ensuring fairness among users. In this article we present two different scheduling algorithms for the uplink (UL) connection. One is a combination of legacy scheduling algorithms earliest deadline first (EDF) and weighted fair queuing (WFQ). The other proposed algorithm is a cross-layer algorithm that pledges fairness among admitted connections and it also supports all service classes. The proposed scheduling algorithms are compared to several other scheduling algorithms for UL traffic under different mixes of traffic and for various characteristics of the IEEE 802.16 MAC layer such as UL burst preamble, frame length and bandwidth request mechanisms. Simulation results indicate that legacy scheduling algorithms are not suitable for the multi-class traffic in IEEE 802.16 since they do not explicitly incorporate the QoS parameters for the given standard.
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