Performance modeling and evaluation of IEEE 802.11 IBSS power save mode

The IEEE 802.11 standard defines a power management algorithm for wireless LAN. In the power management for Independent Basic Service Set (IBSS), time is divided into Beacon Intervals (BIs) and each BI is divided into an Announcement Traffic Indication Message (ATIM) window and a data window. The stations that have successfully transmitted an ATIM frame within the ATIM window compete to transmit data frames in the rest of the BI. This paper analyzes the performance of the IEEE 802.11 Power Save Mode (PSM) in single hop ad hoc networks using a discrete-time Markov chain for a data frame transmission together with the corresponding ATIM frame transmission. The paper presents an analytical model to compute the throughput, average delay and power consumption in IEEE 802.11 IBSS in PSM under ideal channel and saturation conditions. The impact of network size on the throughput, delay and power consumption of the IEEE 802.11 DCF in Power Save Mode is also analyzed. This can be used to find an efficient scheme that can maximize the network throughput while saving power consumption for resource constrained ad hoc wireless networks. The analytical work is validated with simulation results obtained from Qualnet 5.0.1 network simulator.