摘要
随着信息时代和数字世界的来临，数字信号处理得到了飞跃式的发展与进步，已广泛应用于语音、图像、自动控制、航天、航空、医疗和家用电器等众多领域。而在数字信号处理领域中，数字滤波器又占据了十分重要的位置，利用所需要信号和其他信号在频谱上的差别，通过数字滤波器可获得滤除杂波、保持原有信号不变的效果。由于数字滤波器所处理的信号为离散信号，可以用差分方程对其进行描述，用离散变换的方法来分析、处理信号，这样有利于数学分析，又可清楚地描述出所涉及滤波器的形式。
数字滤波器分为有限冲击响应（FIR）和无限冲击响应（IIR）滤波器两大类。与IIR滤波器相比，FIR的实现是非递归的，因而它是稳定的。更重要的是，FIR滤波器在满足频幅响应要求的同时，可以获得严格的线性相位特性。因此，它在高保真的信号处理，如数字音频、图像处理、数据传输以及生物医学等领域得到广泛应用。
本文主要研究数字滤波器的基本理论，并对有限冲击响应数字滤波器FIR的设计和实现进行了分析和研究，本课题主要用MATLAB软件设计FIR数字滤波器，然后应用DSP集成开发环境-CCS编写程序，实现对输入信号进行滤波并用模拟器进行仿真。
关键词：数字滤波器，FIR，MATLAB，DSP
Abstract
With the information times and digital world coming, Digital signal processing got skip-type development and progress ，it had been widely used in voice and image, automatic control, aerospace, aviation, health care and household appliances,etc。 And in digital signal processing fields, digital filters and occupy the important position。 Using the signal and other signals needed to differences in spectrum can be obtained through digital filters filter clutter, keep the original signal unchanged effect。As digital filter processing signal for discrete signal, it can use to describe the difference equations ，and it use discrete transform method to analysis and processing signal, which is conducive to mathematical analysis, but also clearly describe the form of involved filter。
Digital filter are divided into limited shock response （FIR）and infinite shock response(IIR) filter two kinds. Compared with IIR filter, the realization of FIR is recursively, it is stable. More importantly, FIR filters amplitude response in meeting frequency requirements while can acquire strict linear phase characteristic. Therefore, in high fidelity signal processing, such as digital audio and image processing, data transmission and the biomedical sciences，it is widely used.
This article mainly studies the basic theory of digital filter, and the limited shock response digital filter, the design and implementation of FIR is analyzed and studied, this topic is MATLAB software designing FIR digital filters, then apply DSP integrated development environment- CCS debugging is simulated by simulator.
Key words: Digital filter, FIR，MATLAB，DSP
