We study the preservation of impulse response non-negativity, also known as external positivity, for general discretization methods. The results yield new subsets in the space of transfer function coefficients which ensure external positivity. Consequently, linear programming approaches for designing controllers ensuring monotonic step responses are derived for both continuous and discrete-time systems.

中文翻译：

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在线性系统的离散化中保持外部正性

我们研究了一般离散化方法的脉冲响应非负性的保存，也称为外部正性。结果在确保外部正性的传递函数系数空间中产生新的子集。因此，可以为连续和离散时间系统推导出用于设计控制器的线性规划方法，以确保单调阶跃响应。