信号与线性系统的时频域分析：观测已知方波信号、正弦波信号的频谱；观测实时模拟信号的频谱；加深理解时域周期信号的各频率分量在振幅频谱图上所占的比重；观测相位在波形合成中的作用；LTI系统的频域分析，LTI系统对周期性输入信号的响应。-Signals and linear systems with time-frequency domain analysis: observation known square wave signal, sine wave signal spectrum obser

本章重点： 1.离散信号的概念 2.离散信号的运算 3.离散系统的概念 4.离散周期信号的傅立叶级数(DFS) 5.离散非周期信号的傅立叶变换(频谱密度函数DTFT) 6.简单的滤波器(简介) -This chapter focuses: 1. The concept of discrete signal 2. Discrete signal computing 3. The concept of discrete-time systems 4. Discrete F