This paper addresses the problem of state and unknown input estimation for linear discrete-time systems subject to unknown but bounded process disturbance and measurement noise. The existing methods treat this problem based on coordinate transformation, which is complex and may incorporate some conservatism. Unlike the existing methods, we estimate the state and unknown input simultaneously based on an augmented approach. Then a novel observer structure and an L_∞ norm based approach are presented to obtain a tight interval of estimation. The viability and validity of the proposed method are demonstrated by numerical simulations.

中文翻译：

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线性离散时间系统的状态和未知输入的间隔估计

本文针对线性离散时间系统的状态和未知输入估计问题，该系统受到未知但有界的过程干扰和测量噪声的影响。现有的方法基于坐标变换来解决该问题，坐标变换是复杂的并且可能包含一些保守性。与现有方法不同，我们基于增强方法同时估计状态和未知输入。然后一个新的观察者结构和大号_∞范数为基础的方法被呈现以获得估计的紧密间隔。数值仿真表明了该方法的可行性和有效性。