进一步理解FIR滤波器的线性相位特性，熟悉四种线性相位FIR滤波器的幅频特性、相频特性和零点分布情况。

2．掌握用窗函数法设计FIR数字滤波器的原理及方法，了解各种窗函数对滤波器性能的影响。

3. 掌握用频率采样法设计FIR数字滤波器的原理及方法，了解不同的采样点数和不同的过渡带点数对滤波器性能的影响。-Further understanding of the characteristics of linear phase FIR filter, familiar four linear phase FIR filter amplitude-frequency characteristics, phase-frequency characteristics and zero distribution. 2. Master the principles and methods to design FIR digital filter with a window function method to understand the impact of the various window function of filter performance. 3. Grasp the principles and methods to design FIR digital filters using frequency sampling method, to understand the impact of the different sampling points and the different points of the transition zone of the filter performance.