毕业设计（论文）-基于MATLAB的IIR_DF的设计及应用精选.docxVIP

摘 要数字滤波器是数字信号处理中的重要组成部分，它的作用是可以从复杂的信号中提取所需要的信号，抑制不需要的信号。它在通信、系统控制、电力系统、故障检测、语音、图像、自动化仪器、航空航天、铁路、生物医学工程、雷达、声纳、遥感遥测等领域里已有广泛应用。数字滤波器分为经典滤波器和现代滤波器两大类型。经典滤波器又分为有限长脉冲响应数字滤波器（FIR）和无限长脉冲响应数字滤波器（IIR）。本论文主要论述的是IIR数字滤波器，首先介绍它的原理及设计方法（直接法和间接法），然后在MATLAB环境下编程实现。间接法设计IIR数字滤波器就是用数字滤波器的频率特性去模仿模拟滤波器的频率特性。模拟低通滤波器的逼近函数有巴特沃斯型、切比雪夫型、椭圆型，映射方法有冲击响应不变法、双线性变换法等。直接法将采用最小二乘法。关键词：IIR数字滤波器；模拟滤波器；最小二乘法AbstractDigital filter is an important part in Digital Signal Processing. It extracts required signals from complex signals and suppresses unwanted signals. It has been widely used in fields of communication, system control, power system, fault detection, audio, video, automation equipments, aerospace, railway, biomedical engineering, radar, sonar, and remote sensing, etc.Digital filter is divided into two types, classic filter and modern filter. Classic filter is also divided into Finite Impulse Response digital filter and Infinite Impulse Response digital filter. This thesis primarily dissertates about Infinite Impulse Response digital filter, firstly introducing its principle and design methods (direct method and indirect method), then realizing it by programming under MATLAB.Indirect design method is to simulate frequency characteristics of analog filters by that of digital filters. Approximating functions of analog low-pass filters include Butterworth-type, Chebyshev-type and elliptic type when mapping methods contain the same impulse response method, bilinear transformation method and so on. Direct design method of Infinite Impulse Response digital filter adopts least square method.Keywords:Infinite Impulse Response digital filters; The bilinear transformation method; Least square method目 录1 绪论11.1 概述11.2 背景、国内外发展和意义11.3 本论文主要研究内容32 IIR数字滤波器的设计原理及方法42.1 IIR数字滤波器的特点42.2 利用间接法设计IIR数字滤波器52.2.1 设计原理52.2.2 模拟低通滤波器的逼近62.2.3 映射方法162.2.4 频率转换252.3 利用直接法设计IIR数字滤波器283 在MATLAB环境下实现IIR数字滤波器293.1 MALAB软件在数字信号处理中的应用简介293.2 巴特沃斯滤波器设计303.3 切比雪夫Ⅰ型滤波器设计313.4 切比雪夫Ⅱ型滤波器设计333.5 椭圆滤波器设计354 IIR