Sleep mode operation for IEEE 802.16e UGS based WiMAX

To solve the problem of energy efficiency drop in wireless metropolitan area network communication due to frequently sleep-awake transitions, the energy-saving mechanism of the sleep mode operation was researched in WMAN. In this paper we propose a dynamic algorithm to tune the ratio of the sleep windows and receive windows according to the real time load. Then, a Markov chain model was set up to analyze the energy efficiency and mean access delay. NS2 simulation results show that the proposed algorithm can achieve marked gain in energy efficiency compared to the traditional energy saving mechanism.