Performance Evaluation for the Sleep Mode in the IEEE 802.16e with Correlated Traffic

How to control energy consumption is one of the most important issues for the battery-powered mobile stations in mobile networks. IEEE 802.16e standard proposes an energy saving mechanism that named "sleep mode" for conserving the power of the mobile stations. According to the operating mechanism of the sleep mode for downlink traffic in the type I power saving class, modeling the data frames arrival process as a D-BMAP (Discrete-time Batch Markovian Arrival Process), a DBMAP/G/1 queueing model with a close-down time and multiple inhomogeneous vacations is built in this paper. By employing factorization property and Little's law, this queueing model is analyzed. Correspondingly, we get the performance measures of the energy saving ratio, the average data frame delay time, and the system handover ratio for the sleep mode in the IEEE 802.16e. Finally, numerical results are given to demonstrate the dependency relationships between the system performance measures and the system parameters.