窗函数设计FIR数字滤波器论文.doc

摘 要 在数字信号处理中，数字滤波器占有极其重要的地位。数字滤波器是一个能够完成待定任务的离散时间系统，它可以利用有限精度算法来实现。现代数字滤波器可以用软件或设计专用的数字处理硬件两种方式来实现。用软件实现数字滤波器的优点是，随着滤波器参数的改变，很容易改变滤波取的性能。有限长单位冲激响应（FIR）数字滤波器因其严格的线性相位而在数字通信、语音信号处理及自适应信号处理等领域得到了广泛的应用。 本文讲述了有限长单位冲激响应（FIR）数字滤波器的原理，对FIR数字滤波器的窗函数设计方法进行了研究。窗函数法在FIR数字滤波器的设计中有着广泛的应用。传统的数字滤波器设计方法繁琐而且不直观，本文利用MATLAB具有强大的科学计算和图形显示这一优点，与窗函数法设计理论相结合共同设计FIR数字滤波器，不但使设计结果更加直观，而且提高了滤波器的设计精度，从而更好的达到预期效果。 关键字：数字信号处理；FIR滤波器；窗函数。 Abstract In digital signal processing, digital filter of the utmost importance. Digital filter is able to complete the pending tasks for discrete time systems, it can be achieved using the finite precision algorithm. Modern digital filter can be designed with software or dedicated digital signal processing hardware to achieve in two ways. Digital filter with the advantages of software, with the change of filter parameters, it is easy to change the filter to take the performance. Finite Impulse Response (FIR) digital filters because of the strict linear phase in digital communications, speech signal processing and adaptive signal processing and other fields has been widely used. This article describes the units of finite impulse response (FIR) digital filter theory, on the FIR digital filter design window function was studied. Window function in the design of FIR digital filter has a wide application. Conventional digital filter design method cumbersome and not intuitive, this paper MATLAB is a powerful scientific computing and graphical display of this advantage, and the window method combines design theory to design FIR digital filter, the design results not only more intuitive, and improve the accuracy of the filter design to better achieve the desired results. Key words: Digital signal processing; FIR filter; window function. 目 录 引言 1 1 绪论 1 1.1 数字信号处理的概述 1 1.1.1数字信号处理的任务 1 1.1.2数字信号处理系统 2 1.2 滤波器的的概念 2 1.2.1滤波器的定义 2 1.2.2滤波器的分类 2 1.3 MATLAB简介 2 2 数字滤波器的概述 3 2.1 数字滤波器的分类与结构 3 2.2.1 数字滤波器的分类 3 2.2.2FIR滤波器的基本结构 4 2.2