Performance analysis and evaluation for power saving class type III in IEEE 802.16e network

Abstract

In this paper, we present an enhanced power saving class (PSC)type III by introducing a sleep-delay mechanism into theconventional PSC type III in the IEEE 802.16e network. Twomultiple vacation queueing models: without sleep-delay and withsleep-delay, are built to capture the working principles of theconventional PSC type III and the enhanced PSC type III,respectively. Then, using the boundary state variable theorymethod, we analyze these queueing models and give the performancemeasures in terms of the switch ratio, the power saving ratio, theaverage response time and the system utility for both theconventional and the enhanced power saving schemes. Next,numerical results are given to demonstrate the dependencyrelationships between the performance measures and the sleepwindow size. Moreover, we compare the performance of the bothsystems without sleep-delay (the conventional PSC type III) andwith sleep-delay (the enhanced PSC type III) to validate theeffect of the sleep-delay mechanism in the enhanced PSC type IIIproposed in this paper. Finally, we also construct a cost functionto determine the optimal time length of the sleep-delay timer forminimizing the cost function.