Energy-aware QoS uplink scheduling for UGS traffic services in WiMAX

This paper presents new energy-aware QoS scheduling and call admission control algorithms for WiMAX IEEE 802.16e broadband wireless access standard. The scheduling algorithm works at MAC layer and is designed towards minimizing power consumption at mobile stations supporting multiple UGS connections, while meeting the QoS requirements of the connections. The scheduling algorithm uses a novel idea to fill an active OFDM frame as much as possible in order to increase the number of OFDM frames in sleep mode at mobile station. The algorithm also considers the dynamic nature of connection joining and termination, and the schedule adjusts itself on a new connection arrival. We used VoIP traffic connection models to simulate and validate our algorithms. Simulation results show that a power saving in the range of 50-75% can be easily achieved at the mobile station under low-to-moderate traffic intensities.