Wireless synchronisation as a control problem embedded in new-generation networked automation systems

In the present and rapidly evolving industrial scenario, wireless networked controls are gaining importance. This brings about new problems concerning the use of the radio channel, as well as the energy efficiency of the involved devices (often running on battery). We argue that such problems, among which a fundamental one is clock synchronisation, should be addressed by dedicated control structures embedded in the used hardware/software architecture, and that the construction of the said controls should follow strictly system-theoretical principles to the maximum extent. In this paper, building on previous experience, we present such a synchronisation solution together with a formal model for its operation, also accounting for non-idealities in the reference time base. Some experimental results are reported to support the statements made.