An energy-efficient MAC layer scheme for 802.11-based WLANs

This paper focuses on energy saving in 802.11-based WLANs. Typically, 802.11 wireless interfaces consume a significant amount of energy. Previous work has shown that the power saving function specified in the IEEE 802.11 standard is not enough to ensure energy efficiency; thus, other solutions to energy saving are highly needed. Here we consider the 802.11 distributed access scheme and explore the possibility to increase the time period that a wireless station spends in the low-power operational state, the so-called doze state. The key feature of the proposed mechanism is that it enables a station to enter the doze state during channel contention, by exploiting the virtual carrier sense mechanism and the backoff function. By using the network simulator ns-2, we compare the performance obtained through our scheme with the results attained when the standard DCF mechanism is employed.