A Simplified Layered QoS Scheduling Scheme in OFDM Networks

A simplified layered scheduling scheme is presented, which is based on utility-based scheduling, such as Max-Delay- Utility (MDU) scheduling in this paper. In this scheme, the scheduling is divided into two steps-- macro and micro scheduling. In macro step, the utility functions of traffics are defined, according to which the scheduling order of various services is determined. Then in micro step, the scheduling is among all users of the traffic type which is determined in macro step. By simulation in a multi-user orthogonal frequency division multiplexing (OFDM) network, it is demonstrated that the simplified layered MDU scheduling can effectively handle multiple traffic types with diverse QoS requirements and achieve almost the same performance from the view of utility, delay, throughput and fairness as MDU does. Moreover, the simplified layered MDU scheduling has much lower computational complexity than the MDU scheduling and almost the same utility values.