The Design Of QoS Architecture For WiMAX System

IEEE 802.16 wireless Metropolitan Area Network (MAN) is expected to revolutionize the broadband wireless access technology. In IEEE 802.16d standard, the QoS mechanism was not entirely clear defined all service types, which becomes a hotspot of wireless network research. In this diversified network, the applications such as VoIP, audio/video streaming and FTP proposes different needs of QoS for example delay and rate. Meanwhile, we must also consider to the inherent characteristics of wireless networks, such as location-related errors and burst errors. In many of the relevant papers, the majority merely work on how to allocate the bandwidth for wireless network lacking in consideration of the characteristics of WiMAX system. Orientating on WiMAX system, this paper designed an admission control and bandwidth scheduling architecture with support of multi-service and characteristics of wireless.This paper first introduced the protocol of WiMAX and QoS mechanism related content. Then analyzed the main framework of IEEE 802.16d protocol and the definition of QoS mechanism, and discussed the skeleton of QoS mechanism which included type of services, service flow, QoS parameter set and bandwidth request mechanism, and so forth. Subsequently, with combination of wireless scheduling algorithms and strategies, we established the scheduling policy of WiMAX system. A channel adaptation hierarchical scheduling architecture and admission control for WiMAX was proposed after comparison of current scheduling architectures. It discussed the architecture of the composition of scheduling controller, flow control and two level packet scheduling with the key scheduling algorithms of strategy. In the final, the algorithm simulation of NS-2 proved that this scheduling architecture to effectively deal with real-time service, non-real-time service and best effort service, guaranteed various QoS. It is a good solution to the particularity of wireless channel scheduling problem as well. The QoS architecture we proposed enriched the QoS mechanism of WiMAX standard, which can be generalized for many applications.