Observer-Based Resilient Controller Design for Networked Stochastic Systems Under Coordinated DoS and FDI Attacks

Resilient estimation/control networked systems against denial-of-service (DoS) attacks or false data injection (FDI) attacks has been extensively studied. However, most of the existing works focus on the deterministic networked systems. Because of the highly hybrid dynamic nature of the stochastic networked control systems (NCSs) under coordinated DoS and FDI attacks, it is a very challenging problem to consider FDI attack estimation and DoS-resilience control of the stochastic NCSs simultaneously. To tackle this issue, this paper presents a piecewise extended observer-based control framework of stochastic NCSs subject to both DoS and FDI attacks. This simplifies the observer error system modeling of the attacked stochastic NCSs with immeasurable states in the presence of DoS attacks and FDI attacks, thus reducing the difficulty of observer-based resilient controller design. An attack-parameter-dependent time-varying stochastic Lyapunov function is introduced to analyze the mean square exponential stability of the resultant error system, and a co-design method of a piecewise extended observer gain and L₂ controller gain is proposed as well. Finally, simulation studies on an aircraft system are performed to verify the effectiveness of the proposed method.