Adaptive Delta-modulation Coding for Networked Controlled Systems

This work investigates the closed-loop properties of the differential coding scheme known as delta-modulation (Delta-M) when used in feedback loops within the context of linear systems controlled through some communication network. Our main contribution is to propose and adaptive law for parameter Delta, the resolution of the differential state encoder. The adaptation law is defined exclusively in terms of information available at ends of the communication channel, using only two past samples. With minimal implementation and memory usage, global asymptotic stability of the networked controlled system is achieved for a class of unstable plants.