Constructing schedules for time-critical data delivery in wireless sensor networks

Wireless sensor networks for industrial process monitoring and control require highly reliable and timely data delivery. To match performance requirements, specialised schedule based medium access control (MAC) protocols are employed. In order to construct an efficient system, it is necessary to find a schedule that can support the given application requirements in terms of data delivery latency and reliability. Furthermore, additional requirements such as transmission power may have to be taken into account when constructing the schedule. In this article, we show how such schedule can be constructed. We describe methods and tools to collect the data necessary as input for schedule calculation. Moreover, due to the high complexity of schedule calculation, we also introduce a heuristic.We evaluate the proposedmethods in a real-world process automation and control application deployed in an oil refinery and further present a long-term experiment in an office environment. Additionally, we discuss a framework for schedule life-cycle management.