Clock synchronization for energy-constrained wireless sensor networks

Due to the ability of sensor nodes to collaborate, time synchronization is essential for many sensor network operations. This work presents a novel clock synchronization method for energy-constrained wireless sensor networks (WSNs). To conserve WSN energy, this study adopts the flooding time synchronization scheme based on one-way timing messages. Via the proposed approach, the maximum-likelihood (ML) estimation of clock parameters, such as clock skew and clock offset, can be obtained for clock synchronization. Additionally, with the proposed scheme, the clock skew and offset estimation problem will be transformed into a problem independent of random delay and propagation delay. In addition to good performance, the proposed method has low complexity.