This paper focuses on the fundamental problems of linear quadratic gaussian (LQG) control and stabilization problems for networked control systems (NCSs) with unreliable communication channels (UCCs) where packet dropout, input delay and observation delay occur. These basic issues have attracted extensive attentions due to broad applications. Our contributions are as follows. For the finite horizon case, without time-stamping technique, the optimal estimator is derived by using the novelty method of innovation sequences based on the delayed intermittent observations; A necessary and sufficient condition for the optimal control problem is presented on the basis of the solution to the forward and backward difference equations (FBDEs) and two coupled Riccati equations. For the infinite horizon case, it is shown that under certain assumption, the system can stay bounded in the mean square sense if and only if the algebraic Riccati equation admits the unique positive solution.

中文翻译：

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具有不可靠通信通道的网络化控制系统的进一步研究

本文重点研究具有不可靠通信信道 (UCC) 的网络控制系统 (NCS) 的线性二次高斯 (LQG) 控制和稳定问题的基本问题，其中发生数据包丢失、输入延迟和观察延迟。这些基本问题由于应用广泛而受到广泛关注。我们的贡献如下。对于有限时域情况，在不使用时间戳技术的情况下，利用基于延迟间歇观测的创新序列新颖性方法推导出最优估计量；在求解前向和后向差分方程(FBDEs)和两个耦合Riccati方程的基础上，给出了最优控制问题的充分必要条件。对于无限视界的情况，表明在一定的假设下，