1、 本科毕业设计本科毕业设计( (论文论文) ) (2012 届) 论文题目论文题目 基于Matlab的FIR低通滤波器设计 (英文) Design of FIR Low-pass Digital Filter Based on Matlab 所在学院 电子信息学院 专业班级 学生姓名 指导教师 指导教师 职称 完成日期 年 月 日 摘 要 FIR数字滤波器是数字信号处理的一个重要组成部分， 由于FIR数字滤波器具有严 格的线性相位，因此在信息的采集和处理过程中得到了广泛的应用。本文介绍了FIR 数字滤波器的概念和线性相位的条件，分析了窗函数法、频率采样法和等波纹逼近法 设计FIR滤波器的思路和
2、流程。在分析三种设计方法原理的基础上，借助Matlab仿真 软件工具箱中的fir1、fir2和remez子函数分别实现窗函数法、频率采样法和等波纹逼 近法设计FIR滤波器。仿真结果表明，在相频特性上，三种方法设计的FIR滤波器在通 带内都具有线性相位；在幅频特性上，相比窗函数法和频率采样法，等波纹逼近法设 计FIR滤波器的边界频率精确，通带和阻带衰减控制。 关键词：关键词：FIR数字滤波器；窗函数法；频率采样法；等波纹逼近法；Matlab Abstract In a digital signal, there will be some interference signal which sys
3、tem does not needed often. So we need to use digital filtert to filter the signal to extract the useful signal. FIR digital filter is an important component of digital filter.As the FIR digital filters linear phase response is required, it have been widely used in information collection and processi
4、ng. This paper introduced the concept of FIR digital filters and the general idea of the design, Introducting and compareding the advantages and disadvantages of three kinds of the FIR filter design method, and respectively design filter using the window function method, the frequency sampling metho
5、d and wave approximation method. Especially in digital signal processing, Matlab is widly used which can design requirements It is Intuitive and simple so that greatly reduce the workload. This article is designed by Matlab function and simulated by Matlab software to make the tedious step in the ca
6、lculation simplify.It also drawed the amplitude-frequency characteristic curve relatly. Finally, the original signal and filtered signal are contrasted and analied. Key Words:FIR digital filters，Window function，Frequency sampling，Equiripple approximation method，Matlab 目目 录录 1 引言 . 1 2 FIR 数字滤波器线性相位条件 2 2.1 FIR 数字滤波器概述. 2 2.2 FIR 数字滤波器线性相位定义. 3 2.3 FIR 数字滤波器线性相位时域约束条件. 3 3 FIR 数字滤波器设计方法 5 3.1 FIR 数字滤波器的窗函数设计法. 5 3.1.1 窗函数设计法的设计思路 5 3.1.2 吉布斯效应 7 3.1
