TACO: Temperature-Aware Compensation for Time Synchronization in Wireless Sensor Networks

Time synchronization is critical for wireless sensor networks (WSNs) because data fusion and duty cycling schemes all rely on synchronized schedules. Traditional synchronization protocols assume that wireless channels are available around the clock. However, this assumption is not true for WSNs deployed in intertidal zones. In this paper, we present TACO, a synchronization scheme for WSNs with intermittent wireless channels and volatile environment temperatures. TACO estimates the correlation of clock skews and temperatures by solving a constrained least squares problem, and continuously adjusts the local time with the predicted clock skews according to temperatures. Our experiment conducted in an intertidal zone shows that TACO can greatly reduce the clock drift and prolong the resynchronization intervals.