jichu_3.asv

关于滤波器的一些源程序

%设计采样频率为900Hz，9阶高通滤波器，截止频率为300Hz(butterworth)
clear;clc;close all;
fs=900;
[b,a]=butter(9,300/450,'hig');
[H,w]=freqz(b,a,512);
w=[0:255]*2/fs;
plot(w,abs(H(1:256)));