中文说明：
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。
English Description：
Linear time invariant discrete-time systems can be described by linear difference equations with constant coefficients in time domain, and shock response sequences can describe their time-domain characteristics. In this experiment, matlab function is used to study the time domain characteristics of discrete-time system, so as to deepen the understanding of the difference equation, impulse response and linear and time invariant characteristics of discrete-time system