Frequency tracking synchronization algorithm for high latency wireless sensor networks

Abstract

Time synchronization is a critical issue in distributed systems especially for wireless sensor networks (WSNs). Most existing synchronization algorithms, such as Reference Broadcasts Synchronization (RBS), Time-sync Protocol for Sensor Networks (TPSN), Flooding Time Synchronization Protocol (FTSP) and etc., assumed instantaneous communication between the pair of nodes intended for synchronization, which is however hard to implement in high latency systems. Time Synchronization for High Latency networks (TSHL) is another algorithm to address this problem for short range networks and ideally assumes constant clock skew during synchronization, which is impractical for longer communication distance with higher latency and viable clock skew. By analyzing the compensating error of TSHL, we proposed a novel frequency tracking synchronization algorithm for high latency networks. Numerical results suggest that the proposed algorithm works well for variable clock skew and outperforms TSHL scheme.