Achieving Quality of Service in Group Scheduling in Cellular Networks

Title from PDF of title page, viewed on July 17, 2014Thesis advisor: Cory BeardVitaIncludes bibliographic references (pages 51-55)Thesis (M. S.)--School of Computing and Engineering. University of Missouri--Kansas City, 2014Cellular 3G/4G networks provide a wonderfully rich set of applications and social networking capabilities. From a QoS perspective, the traffic is basically divided into Real time and Non real time traffic which helps in scheduling priorities to the packets. With increase in need for QoS in the commercial networks, scheduling schemes such as MLWDF (Modified Largest Weighted Delay First) are playing a prominent role in deciding factors of packet selection. But most of these features are not available to public safety and emergency organizations where these organizations must use dedicated systems to obtain the reliability and protected performance that is needed. This research work provides a brief survey of the regulatory and commercial issues involved. The research work then provides solutions to give real-time and non-real-time traffic scheduling priorities to balance different requirements. We introduce the concept of a queue indicator that uses queue awareness to decide which traffic type to transmit. Then we introduce the concept of group scheduling that adds together scheduling metrics of different users within groups to decide which groups should transmit. These metrics are both opportunistic to take advantage of changing channel conditions and they are queue aware to adapt to traffic conditions. But the metrics are very simple so that scheduling mechanisms are practical and scalable for implementations. These are all evaluated through a detailed simulator (MATLAB-Simulator) that models long-term and short-term fading impacts. We find the best queue indicator values and then assess different cases where groups have various delay requirements. With the ever increasing number of users and the usage of data in cellular networks, meeting the expectations is a very difficult challenge. To add to the difficulties, the available resources are very limited, so proper management of these resources is very much needed. Scheduling is a key component and having a scheduling scheme which can meet the QoS requirements such as Throughput, Fairness and Delay is importantAbstract -- List of illustrations -- List of tables -- Acknowledgements -- Introduction -- Background -- Scheduler design and related work -- Matlab -- Results and analysis - Reference

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