Optimal Control and Stabilization for Networked Control Systems With Packet Dropout and Input Delay

This brief is concerned with the control problem for discrete-time networked control systems. It is assumed that state and control signals transmit through an unreliable communication channel, where packet dropout and input delay occur simultaneously. The main contributions are twofold. First, we obtain the optimal LQR controller, which is a linear function of the optimal state estimator, with the feedback gain based on a standard difference Riccati equation. It is noted that the state estimator and the controller can be calculated separately. Second, a necessary and sufficient condition for the mean-square stabilization is derived. It should be stressed that the eigenvalues of the system matrix and the packet dropout probability determine the stabilizing condition, which is uncorrelated with input delay.