Networked LQG control over unreliable channels

In this article the Linear Quadratic Gaussian (LQG) optimal control problem for networked control systems when data is transmitted through a TCP-like network and both measurement and control packets are subject to random packet dropouts, is addressed for two cases. In the first case it is assumed that the control acknowledgment packets in TCP-like protocols are always available and we pròpose how to design a linear optimal “hold-input” control law for this case. In the second problem, we assume the acknowledgement packets may go missing with a known probability. We derive a suboptimal linear estimation-control law for this part. Simulation results are presented to demonstrate the effectiveness of the proposed approaches.