RMTS: A robust clock synchronization scheme for wireless sensor networks

In recent years, wireless sensor networks (WSNs) have attracted more and more attention, but some applications of WSNs are still restricted by various factors, one of which is the clock synchronization among nodes. It is difficult to estimate the noises caused by communication delay, clock drift and measurement errors, which makes it challenging to achieve accurate clock synchronization. In this paper, we consider a bounded noise model, which does not need to satisfy any fixed probability distribution, nor does it need to have a fixed mean or variance. Under this noise model, we propose a novel clock synchronization scheme based on maximum consensus, which is called Robust Maximum Time Synchronization (RMTS). The proposed RMTS scheme starts with the estimation of relative skew and offset. On the basis, software parameters are adjusted so that all the nodes in the network can have the same software skew and offset. We theoretically prove that the proposed scheme can guarantee the accuracy of clock synchronization. Simulations are conducted to validate the effectiveness of the proposed scheme. The performance comparison with the other two schemes demonstrates that the RMTS scheme outperforms the existing ones.