Resource management strategies for quality of service in IEEE 802.16 networks.
Raghu K Ramadurai
Date of Issue2009
School of Electrical and Electronic Engineering
Positioning and Wireless Technology Centre
WiMAX is an industry standard for wireless broadband to provide last mile internet access as an alternative to wired broadband such as cable and DSL. The Physical, Medium Access Control and Security layers for this are specified by the IEEE 802.16 series of standards. The standards aim at providing Quality of Service for different multimedia traffic like voice, video and data that have different service requirements. Though the standards emphasize on handling different traffic classes according to their QoS requirements, the details of resource management is left unspecified. The most recent multi-hop relay standard (802.16j) aimed at increasing the WiMAX base station coverage also requires an efficient packet scheduling architecture at each hop to provide QoS to different traffic classes. In our thesis, we have proposed fixed and adaptive queue-aware uplink scheduling principles which will efficiently share bandwidth among different traffic classes to provide QoS in a Point to Multi-Point topology. The uniqueness of our strategy is that it schedules real-time and non real-time traffic flows together such that real-time traffic can achieve the good delay performance while keeping non real-time traffic within their buffer limits. We have also proposed a scheduling architecture to support QoS over multiple hops by using relay stations as specified in IEEE 802.16j standard. The proposed scheduling strategy effectively combines centralized and distributed resource allocation principles to provide the required QoS for different traffic classes. The architecture and scheduling algorithm are compatible with the legacy IEEE 802.16 standard and hence does not need any functional change at the subscriber stations. We have also proposed a modified Earliest-Due Date scheduling scheme that out performs the Strict Priority queuing and also provides fair resource allocation to lower layers of the Relay Tree.
DRNTU::Engineering::Electrical and electronic engineering