Synchronization Considerations for Real-Time Wireless Sensor and Actuator Networks

Wireless sensing and networking technologies have taken a strong foothold in the process control industry. The focus has now shifted towards applying control with wireless technology. As such, the current industrial wireless sensor network architectures are under increased scrutiny about their real-time, reliability, and security performances. In this paper, we take a renewed look at network synchronization, the basic building block to support real-time activities. We present our analysis, key observations, and recommendations. We also get into the depth of WirelessHART, the most deployed industrial wireless network architecture, and affirm that, with good practice, we could achieve highly reliable synchronization to provide guaranteed packet deliveries. The correctness of the time synchronization analysis in both line and mesh network topologies is verified through extensive simulation experiments.