针对离散系统进行开环、闭环分析；绘制Bode、Nyquist、根轨迹图；阶跃、脉冲响应，并均给出响应的图示。-For the discrete system closed loop analysis of ring, open　drawing Bode, Nyquist, root locus diagram　step, impulse response, and the response of the diagrams are given.