Temperature-aware Time Synchronization with an Accuracy-efficiency Trade-off in Wireless Sensor Networks
Wasan Lasoi, Sataporn Pornpromlikit · Procedia Engineering · 2016
For many wireless sensor network (WSN) applications, maintaining accurate time information is crucial. The synchronization process, however, involves frequent message exchanges among wireless nodes, which quickly drain their limited energy resources. In this work, we propose a temperature-aware time synchronization technique that efficiently corrects both clock time offset and frequency offset (skew) in real time. After each correction, the clock skew is small enough that the client node can turn off its transceiver for a certain period of time or until there is a change in temperature to save its battery life. From our experiments, the proposed protocol with 10 minutes of sleep time period still achieves high accuracy with infrequent peaks of time offset below 0.2 ms, while the energy efficiency is improved by more than a factor of two despite a large variation in temperature.