%利用Filter函數(shù)進(jìn)行濾波器設(shè)計(jì)
t=0:0.001:0.2;
x1=sin(2*pi*40*t);
x2=0.5*rand(size(t));
x=x1+x2;
A=[1 -1.143 0.4128];
B=[0.06745 0.1348 0.06745];
y=filter(B,A,x);
plot(t,x1,'g*',t,x,'r:',t,y,'b-');
legend('原始信號','加噪后信號','濾波后信號');