hanning_fre.m

经典《信号与系统》教程的matlab例程,对深入理解信号与系统相关概念有很大帮助

w=-pi:0.1:pi;
N=8;
WR=0.5*(sin(w*N/2)+eps)./(sin(w/2)+eps);
WR1=0.25*(sin((w-2*pi/N)*N/2)+eps)./(sin((w-2*pi/N)/2)+eps);
WR2=0.25*(sin((w+2*pi/N)*N/2)+eps)./(sin((w+2*pi/N)/2)+eps);
WH=WR+WR1+WR2;
subplot(211)
plot(w,WR,'r'),hold on
plot(w,WR1,'k'),hold on
plot(w,WR2,'k'),hold on
axis([-pi,pi,-1,5])
title('The frequency response of the Hanning window')
subplot(212)
plot(w,WH,'r'),hold on
axis([-pi,pi,-1,5])
xlabel('Frequency (radians)')