Smart merging strategy for configuring power saving parameters in IEEE 802.16 mobile WMANs

Abstract

The IEEE 802.16e mobile wireless metropolitan area network (WMAN) standard is an emerging technology to support roaming mobility for mobile stations (MSs) in outdoor environment. Because most of MSs are powered by batteries, the standard supports three power saving modes to conserve battery power meanwhile, the different requirements of quality of services are guaranteed. By setting appropriate parameters, single type of power saving mode will work well for prolonging battery life. However, if an MS has established several connections with serving BS and these connections are associated with different power saving types, the sleeping behavior of MS might not follow the parameter settings because MS actually enters sleep mode only when all the connections of it are assigned to sleep at the same time. In other words, if there is any connection is in active mode or listening mode during a time frame, then the MS shall not turn down the wireless transceiver. Consequently, the power saving efficiency is degraded by such synchronizations. In order to minimize the power consumptions in MSs, this paper proposes a smart parameter merging strategy (PMS) for the base station (BS) to configure the parameters of power saving classes for MSs with multiple connections. The simulation results show that the proposed strategy has better performance of both the power consumption and the packet access delay compared to the standard strategy.