本课程是通信、电子与信息等相关专业的专业必修课,对本 专业后续课程诸如数字信号处理、通信原理等专业课起着承上启 下的作用 主要内容包括:1、信号与系统的描述、分类、模型;2、连 续时间系统的时域分析(模型建立与求解,零输入响应与零状态 响应,卷积);3、傅立叶变换与信号的频谱分析:4、拉氏变换

第8章数据插值、函数逼近问题的计算机求解 一、插值与数据拟合 二、样条插值与数值微积分问题求解 三、由已知数据拟合数学模型 四、特殊函数及曲线绘制 五、信号分析与数字信号处理基础

7.1 电路 7.2 信号与系统课程 7.3 数字信号处理 7.4 静力学 7.5 运动学 7.6 测量学 7.7 文献管理 7.8 经济管理

7.1 MATLAB在信号与系统中的应用 7.2 MATLAB在数字信号处理中的应用 7.3 MATLAB辅助神经网络分析与设计 7.4 MATLAB辅助模糊系统分析与设计

Discrete-Time Systems A discrete-time system processes a given input sequence x[] to generates an output sequencey[n] with more desirable properties In most applications, the discrete-time system is a single-input, single-output system:

The dtft provides a frequency-domain representation of discrete-time signals and lti discrete-time systems Because of the convergence condition, in many cases. the dtft of a sequence may not exist as a result. it is not possible to make use of such frequency-domain characterization in these cases Copyright C 2001, S K. Mitra

the Transform Domain An LTI discrete-time system is completely characterized in the time-domain by its impulse response {h[n]} We consider now the use of the DTFT and the z-transform in developing the transform￾domain representations of an LTI system

It is nearly impossible to design a linear￾phase IIR transfer function It is always possible to design an FIR transfer function with an exact linear-phase response Consider a causal FIR transfer function H(z) of length N+1, i.e., of order N:

Later in the course we shall review various methods of designing frequency-selective filters satisfying prescribed specifications We now describe several low-order FIR and IIR digital filters with reasonable selective frequency responses that often are satisfactory in a number of applications

The simple filters discussed so far are characterized either by a single passband and/or a single stopband There are applications where filters with multiple passbands and stopbands are required The comb filter is an example of such filters