%exa031101_fftfilt.m,to test fftfilt.m,
h=firl(10，0.3，hanning(11));
N=500;p=0.05;f=1/16;
u=randn(1,N)*sqrt(p);
s=sin(2*pi*f*[0:N-1]);
x=u(1:N)+s;
y=fftfilt(h,x);
subplot(211);plot(x);
subplot(212);plot(y);