Improved dynamic power management in wireless sensor networks

Wireless sensor networks play a key role in monitoring remote or inhospitable physical environments. One of the most important constraints is the energy efficiency problem. Power conservation and power management must be taken into account at all levels of the sensor networks system hierarchy. Especially, DPM (Dynamic Power Management) technology, which shuts down the devices when not needed and wake them up when necessary, has been widely used in sensor networks. In this paper, we modify the sleep state policy developed by Simunic and Chdrakasan in [1] and deduce a new threshold satisfies the sleep-state transition policy. Nodes in deeper sleep states consume lower energy while asleep, but require longer delays and higher latency costs to awaken. Implementing dynamic power management with considering the battery status and probability of event generation will reduce the energy consumption and prolong the whole lifetime of the sensor networks. The sensor network consumed less energy in our simulation than that in [1].