Power-Efficient Clock Synchronization Using Two-Way Timing Message Exchanges in Wireless Sensor Networks

A number of time synchronization protocols for Wireless Sensor Networks (WSNs) have been recently proposed aiming at maximizing the accuracy and minimizing the power efficiency. This paper proposes novel clock skew estimators for the protocols based on two-way timing message exchanges to achieve long term reliability of synchronization. The proposed clock synchronization mechanism is far more power efficient than the conventional ones by significantly increasing the resynchronization period. Moreover, it can be applied to the conventional protocols without any additional overhead. In fact, the proposed estimators assume simple steps and low complexity, a feature which is strongly demanding for WSNs consisting of cheap and small nodes.