Situation-Aware Hybrid Time Synchronization Based on Multi-Source Timestamping Uncertainty Modeling

Timestamping accuracy is of the utmost importance to achieve accurate time synchronization of large-scale connected systems. However, the heterogeneity and complexity inherent to Internet of Things (IoT) systems lead to multi-source timestamping uncertainties and significantly deteriorate performance of traditional inflexible synchronization methods. In this paper, a situation-aware hybrid time synchronization protocol is designed based on multi-source timestamping uncertainty modeling and integrated time information exchange mechanism for heterogeneous IoT systems. More specifically, the multi-source timestamping error inherent to the overall synchronization process are accurately modeled by exploring the impact of the multi-faceted operating conditions. By analyzing the real-time timestamping uncertainties, a hybrid time synchronization scheme is actualized, which can achieve optimal synchronization strategy for clock parameters estimation. In addition, an integrated time information exchange mechanism is designed to reduce timestamping redundancy during time synchronization. Simulation results show that the proposed scheme can enhance the synchronization accuracy for heterogeneous operating scenarios.