Optimal sleep time controller based on traffic prediction and residual energy in duty-cycled wireless sensor networks

In duty-cycled wireless sensor networks, energy efficiency and packet latency are two most important metrics in the design of medium access control and routing algorithms. However, these two problems cannot be addressed well at the same time. In this article, we investigate the trade-off between energy consumption and latency and formulate them into a multi-objective optimization problem. By applying the single exponential smoothing method, we estimate the amount of data of next period and design two optimal sleep time controllers according to time scheduling model of network, so as to dynamically adjust the duty cycle of end node. Our controllers also consider the residual energy of end node. Finally, we propose two dynamic and adaptive medium access control algorithms for synchronous and asynchronous duty-cycled wireless sensor networks, respectively. We evaluate our protocols with different parameters and compare them with existing works. Performance results show that our proposed algorithms can balance power consumption among nodes and improve power efficiency while guaranteeing packet latency is minimized.