A dynamic back-off approach in wireless sensor networks for environmental monitoring

Energy awareness is the single most prominent factor of design in all the layers of the protocol stack for wireless sensor networks. A dynamic back-off procedure in which the size of the contention window is influenced by the real time traffic information of the network can be a good remedy to decrease the idle listening time in low loads and the probability of collisions in high loads. In this paper a new approach to dynamically adjusting the contention window size in Sensor Medium Access Control (S-MAC) protocol is investigated. We explore the effect of different duty cycles for different loads on the various performance parameters such as end-to-end latency, delivery ratio, and energy consumption to prove the efficiency of our approach.