QoS scheduling for heterogeneous traffic in OFDMA-based wireless systems

Abstract

In this thesis, we provide a QoS scheduling framework for heterogeneous traffic in OFDMA based wireless systems. The proposed scheduling algorithm achieves two objectives concurrently, satisfying the QoS requirements of the real-time traffic and providing proportional fairness to the non real-time traffic while utilizing the system resources efficiently. Alpha deadline parameter is introduced to control the balance between the QoS provisioning and the opportunity of diversity gain. This simple parameter has powerful controllability which can fully embody the operating strategy of wireless networks. Step-by-step approach is used to achieve low complexity and traffic class prioritization. For QoS scheduling of the real-time traffic, well-known bipartite matching algorithm is adapted to exploit multi-channel diversity more efficiently. For utility maximization scheduling of the non real-time traffic, log utility function based utility maximization algorithm for multi-channel is used to provide proportional fairness. The characteristics of alpha deadline parameter and the performance of proposed scheduler is validated through the extensive simulation results. The proposed QoS scheduling framework on the basis of alpha deadline parameter can maximize synergy effects when incorporated with the other non real-time traffic scheduling frameworks.