中文摘要：

针对存在时变有界时延的网络控制系统，在一定假设条件下，基于分离原理讨论了状态观测器和状态反馈控制器的设计方法。状态观测器通过在开环预测和闭环预测间切换以补偿时延的影响，同时考虑时延的时变性以及回路中长时延的存在，闭环预测也是在多个模型间切换，从而将状态观测器建模成具有多个子系统的离散切换系统。在此基础上，利用预测状态作为控制器的输入，设计了具有圆盘区域极点约束的状态反馈控制器。最后以线性矩阵不等式可行解的方式分别给出了控制器和观测器的构造方法，仿真结果说明了所提出方法的有效性。

英文摘要：

For the networked control systems with time-varying delay, a design method of state observer and state feedback controller is proposed based on separation principle. The observer is switched between open-observer and close-observer to compensate the delay; and the close-observer is also a switched system because the delay is time-varying and sometimes more than one sampling period. Then, based on the predicted state, a state feedback controller is designed which poles are located in a given circle. The parameters of the observers and controller are obtained by solving a group of LMIs, and finally a simulation validates the method proposed.