Energy-Efficient Low Power Listening for Wireless Sensor Networks in Noisy Environments
Low Power Listening (LPL) is a common MAC layer technique for reducing energy consumption in wireless sensor networks, where nodes periodically wake up to sample the wireless channel for activity. However, LPL is highly susceptible to false wakeups caused by environmental noise being detected as energy on the channel, causing nodes to spuriously wake up in order to receive nonexistent transmissions. In empirical studies, the authors demonstrate that the false wakeup problem can significantly increase a node's duty cycle, compromising the benefit of LPL. They also find that adjusting the energy-level threshold used to perform Clear Channel Assessment (CCA) can effectively combat the false wakeup problem.