An Adaptive Weighted Fair Scheduling Algorithm for Wireless Networks

Abstract

In this paper, we present an adaptive weighted fair queueing algorithm (AW-FQ) which can provide better QoS for error-prone flows and does not need to predict the channel quality of packet transmission in the wireless environment. Every flow is guaranteed to receive the minimal tolerable quality of its original service when experiencing channel errors. AW-FQ is suitable for applications that need different minimal QoS requirements. In AW-FQ, each flow is individually assigned a virtual flow which does not always occupy a fixed fraction of the bandwidth. The virtual flow can provide additional service for error-free flows and compensate the flow which it is assigned to. The amount of service degradation of a flow can be administratively controlled within a predefined tolerable ratio when the flow provides compensation. Simulation results show that our approach can guarantee throughput and fairness. Compared to the server based fairness approach (SBFA), AW-FQ has better queueing delay bound and does not have to assign a fixed flow which always occupies a fixed fraction of the bandwidth for providing compensation.