掌握双线性变换法及脉冲相应不变法设计IIR数字滤波器以及窗函数法设计FIR数字滤波器的原理，具体方法及计算机编程。 2.观察双线性变换法，脉冲响应不变法及窗函数法设计的滤波器的频域特性，了解各种方法的特点。 3.用MATLAB画出三种方法设计数字滤波器的幅频特性曲线，记录带宽和衰减量，检查是否满足要求-Master bilinear transform and impulse response invariance IIR digital filter design and window function design FIR digital filter theory, specific methods and computer programming. 2. Observe bilinear transform, impulse response and frequency domain characteristics unchanged Act designed filter window function, understanding the characteristics of the various methods. 3 Draw three methods using MATLAB design of digital filter frequency characteristic curve, record the amount of bandwidth and attenuation, check meets the requirements