An Adaptive Power Saving Strategies based on Cross-layer Design in IEEE 802.16e

To enhance the power efficiency of broadband wireless access devices based on battery power, an adaptive power saving strategies based on cross-layer design is proposed for IEEE 802.16e sleep-mode operation. In this paper, we evaluate performance of the power-saving mechanism based on sleep mode in IEEE 802.16e mobile Worldwide Interoperability for Microwave Access (WiMAX) system, which is based on time scheme to trigger transition from awake mode to sleep mode and a sleep window to next sleep window. After being idle for a period of time, a design time parameter to overcome the flaw of power efficiency drop with the short time sleep, mobile station switch to sleep mode for the first sleep interval defined by initial sleep window, which dynamically tune according to the statistical measurement of traffic load from physical layer . By analyzing the behaviors of a mobile station working in the sleep-mode operation with a Markov chain model and exploring the relationship among traffic, energy consumption and mean delay of power saving mechanism based on cross-layer design, a heuristic algorithm is proposed to adapt the parameters of sleep-mode mechanism to the mobile station traffic and the mean delay requirement. Extensive simulation results show that the proposed algorithm outperforms the traditional power saving mechanisms in both the power consumption and the mean delay.