Distributed-observer-based cooperative control for synchronization of linear discrete-time multi-agent systems

•This paper studies discrete-time output regulation based on distributed protocol.•Distributed observers are constructed for the unmeasurable states.•The stability region and internal model method is used for solving the problem.

This paper considers output synchronization of discrete-time multi-agent systems with directed communication topologies. The directed communication graph contains a spanning tree and the exosystem as its root. Distributed observer-based consensus protocols are proposed, based on the relative outputs of neighboring agents. A multi-step algorithm is presented to construct the observer-based protocols. In light of the discrete-time algebraic Riccati equation and internal model principle, synchronization problem is completed. At last, numerical simulation is provided to verify the effectiveness of the theoretical results.