中文说明：数字滤波器是指输入、输出均为数字信号，通过数值运算处理改变输入信号所含频率成分的相对比例，或者滤除某些频率成分的数字器件和程序。经典数字滤波器从滤波特性上分类，可以分成低通、高通、带通和带阻等滤波器。数字滤波器的幅频特性表示信号通过该滤波器后各频率成分振幅衰减情况，而相频特性反映各频率成分通过滤波器后在时间上的延时情况。 本次课程设计先是对切比雪夫数字带通滤波器有关理论知识作介绍，在性能指标分析基础上运用MATLAB的buttord和butter函数设计程序，得到损耗函数和相频特性函数图像，写出数字滤波器系统函数H(Z)，
English Description：
Digital filter is the input and output are digital signals, through the numerical operation to change the input signal frequency components of the relative proportion, or filter out some of the frequency components of digital devices and procedures. The classical digital filter can be divided into low pass, high pass, band pass and band stop filter. Digital filter of the amplitude frequency characteristic of the signal through the filter of the frequency component amplitude attenuation, and the phase frequency characteristics reflect the frequency components through the filter at the time of the delay.The curriculum design is first of the Chebyshev digital bandpass filter theory is introduced and the performance analysis based on using MATLAB buttord and butter function design program, loss function and phase frequency characteristic function image, write digital filter system function H (z).