说明：  线性时不变离散时间系统在时域中可以通过常系数线性差分方程来描述，冲击响应序列可以刻画其时域特性。本实验通过使用MATLAB函数研究离散时间系统的时域特性，以加深对离散时间系统的差分方程、冲激响应和系统的线性和时不变特性的理解。
(The linear time-invariant discrete-time system can be described in the time domain by a linear difference equation with constant coefficients. The impulse response sequence can describe its time-domain characteristics. This experiment uses MATLAB functions to study the time domain characteristics of discrete-time systems to deepen the understanding of differential equations, impulse response, and linear and time-invariant characteristics of the system.)