图3-1-1不同阶次巴特沃思滤波器的幅频特性.txt

工频数字陷波器的频率特性和不同阶次巴特沃思滤波器的幅频特性

%图3-1-1不同阶次巴特沃思滤波器的幅频特性
ord=3;
[b,a] = butter(ord,0.4);
[h,w]=freqz(b,a,512,1000);
hold on;							%数字滤波器频响
habs=(abs(h));
plot(w,habs);

ord=6;
[b,a] = butter(ord,0.4);
[h,w]=freqz(b,a,512,1000);
hold on;							%数字滤波器频响
habs=(abs(h));
plot(w,habs);

ord=10;
[b,a] = butter(ord,0.4);
[h,w]=freqz(b,a,512,1000);
hold on;							%数字滤波器频响
habs=(abs(h));
plot(w,habs);