www.gusucode.com > signal 案例源码程序 matlab代码 > signal/DesignOfADifferentiatorExample.m
%% Design of a Differentiator % An ideal differentiator has a frequency response given by % $D(\omega)=j\omega$. Design a differentiator of order 30 that attenuates % frequencies above $0.9\pi$. Include a factor of $\pi$ in the amplitude % because the frequencies are normalized by $\pi$. Display the zero-phase % response of the filter. % Copyright 2015 The MathWorks, Inc. %% b = firls(30,[0 0.9],[0 0.9*pi],'differentiator'); fvtool(b,1,'MagnitudeDisplay','zero-phase')