Stabilisation with feedback control utilising packet-dropping network links

The possibility of using networks, such as the Internet, for data transmission between physically distributed sensors and actuators in a system gives rise to several new challenges in control design. An approach is discussed for dealing with missing or delayed information because of packet drops or deteriorating network performance. More specifically, a stochastic set-up is used to find appropriate and optimal conditions for a system to remain stable despite packet drops. Both discrete-time and continuous-time systems are considered. Under reasonable assumptions on the behaviour of the network and the noise model, it is possible to characterise optimal control strategies in terms of the probability of a packet drop, the noise statistics, the instability of the open-loop system and, in the case of continuous-time systems, the sampling frequency.