MATLAB下通过impulse invariant transformation方法设计数字滤波器，包含低通和带通滤波器代码。-Using MATLAB m-file to design LP and BP digital filter by impulse invariant transformation method.

利用双线性不变法和脉冲响应不变法设计模拟带通通滤波器方法-Bilinear invariant law and impulse response method with all analog filter design methods