一、Textbook S.K. Mitra, Digital Signal Processing-A Computer-Based Approach, Third Ed

一、滤波器的图示及分析 二、等效结构 三、基本的FIR滤波器结构 四、基本的IIR滤波器结构

一、频率响应 二、传输函数 三、简单滤波器 四、一些特殊的传输函数

1离散时间信号 2离散时间系统

Linear-Phase FIR Transfer Functions It is nearly impossible to design linear- phase IIR transfer function It is always possible to design an FIR transfer function with an exact linear-phase response

Phase and Group Delays The output y[n] of a frequency-selective LTI discrete-time system with a frequency response(@) exhibits some delay relative to the input x[n] caused by the nonzero phase response 0(@) =arg{()} of the system

Z-Transform 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

Transform-Domain Representation of Discrete-Time Signals Three useful representations of discrete-time sequences in the transform domain: Discrete-time- Fourier Transform(DTFT) YDiscrete Fourier Transform(DFT) z- -Transform

数字信号处理: 是20世纪60年代,随着信息学科和计算机学科 的高速发展而迅速发展起来的一门新兴学科。它 的重要性日益在各个领域的应用中表现出来。 其主要标志是两项重大进展,即快速傅里叶变 换(FFT)算法的提出和数字滤波器设计方法的完善

华南理工大学：《食品加工与保藏原理》课程教学资源（PPT课件）第四章 食品的干燥 第二节 食品在干燥过程发生的变化