www.gusucode.com > signal 案例源码程序 matlab代码 > signal/GroupDelayResponseOfAButterworthDigitalFilterExample.m

    %% Group Delay Response of a Butterworth digitalFilter
% Use |designfilt| to design a sixth-order Butterworth Filter with
% normalized 3-dB frequency $0.2\pi$ rad/sample. Display its group delay
% response.

% Copyright 2015 The MathWorks, Inc.


%%

d = designfilt('lowpassiir','FilterOrder',6, ...
    'HalfPowerFrequency',0.2,'DesignMethod','butter');
grpdelay(d)