基于matlab的数字滤波器设计

淮北煤炭师范学院

2009届学士学位论文

基于MA TLAB的数字滤波器设计

学院、专业物理与电子信息学院

电子信息科学与技术

研究方向基于MATLAB的数字滤波器设计

学生姓名耿博

学号200513432024

指导教师姓名邹锋

指导教师职称讲师

2009 年4 月18

基于MATLAB的数字滤波器设计

耿博

（淮北煤炭师范学院物理与电子信息学院235000）

摘要随着信息时代和数字世界的到来，数字信号处理已成为今一门极其重要的学科和技术领域。数字信号处理在通信、语音、图像、自动控制、雷达、军事、航空航天、医疗和家用电器等众多领域得到了广泛的应用。在数字信号处理应用中，数字滤波器十分重要并已获得广泛应用。

数字滤波是数字信号处理的重要内容，数字滤波器可分为IIR和FIR两大类。对于IIR数字滤波器的设计，需要借助模拟原型滤波器，再将模拟滤波器转化为数字滤波器，文中采用的设计方法是脉冲响应不变法、双向性变换法和完全函数设计法；对于FIR数字滤波器的设计，可以根据所给定的频率特性直接设计，文中采用的设计方法是窗函数法。本文根据IIR滤波器和FIR滤波器的特点，在MATLAB坏境下分别用双线性变换法设计IIR和用窗函数设计FIR数字滤波器，并对采集的语音信号进行分析，最后给出了IIR和FIR对语音滤波的效果。

关键词数字滤波器；IIR ；FIR ；MATLAB

The Design of Digital Filter based on MATLAB

Geng Bo

School of Physics and Electronics Information, Huaibei Coal Industry Teachers‟ College, 235000

ABSTRACT Along with the information age and the digital world arrival, the digital signal processing has become a now extremely important discipline and the area of technology.The digital signal processing in the correspondence, the multitudinous domains the pronunciation such as the image, the automatic control, the radar, the military, the aerospace, the medical service and the domestic electric appliances and so on have obtained the widespread application.In the digital signal processing application, the digital filter are extremely important and have obtained the widespread application.

The digital filter are the digital signal processing important content, the digital filter may divide into IIR and the FIR two main kinds. As for the IIR digital filter design, we need the help of analog prototype filter, and then transform analog filter into digital filter. In the paper we use the design of the pulse response invariable method, the bilinear method and full function design; as for the FIR filter, we can design it directly based on the giving frequency, in the paper it uses the design of the window function.This article according to the IIR filter and the FIR filter characteristic, uses the bilinearity method of transformation under the MATLAB bad boundary to design IIR and to design the FIR numeral filter separately with the window box number, and carries on the analysis to the gathering pronunciation signal, and finally gives IIR and FIR to the pronunciation filter effect.

Keywords Digtial Filter;IIR;FIR;MATLAB

目次

1 引言 (1)

2 数字滤波器及MATLAB语言概述 (2)

2.1 数字滤波器的定义和分类 (2)

2.2 常用滤波器的性能指标 (3)

2.3 MATLAB概述 (6)

3 IIR滤波器设计 (8)

3.1 双线性变换法设计IIR数字滤波器 (8)

3.2 脉冲响应不变法 (12)

3.3 完全设计函数法 (15)

3.4 语音滤波实例 (16)

4 FIR滤波器设计 (21)

4.1 窗函数法 (21)

4.2 FIR滤波器滤波实例 (25)

5 总结 (29)

参考文献 (30)

致谢 (31)