Clock Synchronization Using Expectation-Maximization Algorithm in Wireless Sensor Network

Accurate and efficient clock synchronization algorithm is very important in Wireless Sensor Network (WSN). The existing researches focus on exploring communication delay impact on clock synchronization in wireless sensor network. Considering the physical characteristics of the sensor itself, an adaptive clock synchronization method based on Expectation-Maximization (EM) algorithm is proposed. A general clock offset model based on Kalman Filter model is built and the parameter estimation in this model is achieved adaptively by the EM recursion algorithm. Experiments demonstrate that the proposed method can improve clock synchronization accuracy to some degree.