介绍数字滤波器的定义、分类及实现方法。讨论IIR滤波器、FIR滤波器的设计方法以及如何运用MATLAB中的DSP Blockset工具箱设计数字滤波器。-Introduce the definition of digital filters, classification and realization method. Discussion of IIR filter, FIR filter design methods and how to use DSP Blockset of MATLAB toolbox designed digital filter.