Network synchronization by dynamic diffusive coupling

The problem of controlled network synchronization for a class of nonlinear observable systems interconnected via dynamic diffusive coupling is studied. We construct dynamic diffusive coupling combining a nonlinear observer and an output feedback controller. Sufficient conditions on the systems to be interconnected, on the network topology, and on the coupling strength that guarantee (global) synchronization are derived. Moreover, using the notion of semipassivity, we prove that under some mild assumptions the solutions of interconnected semipassive systems are ultimately bounded. The results are illustrated by computer simulations of coupled FitzHugh-Nagumo oscillators