matlab的窗函数,矩形窗,三角窗,汉明窗,汉宁窗,布莱克曼窗[新版].doc

matlab的窗函数,矩形窗,三角窗,汉明窗,汉宁窗,布莱克曼窗[新版]%N=51%求矩形窗的频率响应图wn=rectwin(51);%矩形窗函数%20*log10(abs(WN))[h1,w]=freqz(wn,1);figure(1);plot(w/pi,20*log10(abs(h1/max(h1))));axis([01-1000]);xlabel('归一化频率/\pi');ylabel('20log_{10}|W(e^{j\omega})|/dB');title('矩形窗的傅里叶变换');set(gca,'YTick',[-100-80-60-40-200])set(gca,'XTick',[0::1])set(gca,'XAxisLocation','top');%设置X轴在上方set(gca,'YAxisLocation','left');%设置Y轴在左方text(1,-108,'\pi');%gtext('\pi');%求三角窗的频率响应图wn1=bartlett(51);[h1,w1]=freqz(wn1,1);figure(2);plot(w/pi,20*log10(abs(h1/max(h1))));axis([01-1000]);xlabel('归一化频率/\pi');ylabel('20log_{10}|W(e^{j\omega})|/dB');title('三角窗的傅里叶变换');set(gca,'YTick',[-100-80-60-40-200])set(gca,'XTick',[0::1])set(gca,'XAxisLocation','top');%设置X轴在上方set(gca,'YAxisLocation','left');%设置Y轴在左方%hanningwn1=hanning(51);[h1,w1]=freqz(wn1,1);figure(3);plot(w/pi,20*log10(abs(h1/max(h1))));axis([01-1000]);xlabel('归一化频率/\pi');ylabel('20log_{10}|W(e^{j\omega})|/dB');title('Hanning的傅里叶变换');set(gca,'YTick',[-100-80-60-40-200]);set(gca,'XTick',[0::1]);set(gca,'XAxisLocation','top');%设置X轴在上方set(gca,'YAxisLocation','left');%设置Y轴在左方%hammingwn1=hamming(51);[h1,w1]=freqz(wn1,1);figure(4);plot(w/pi,20*log10(abs(h1/max(h1))));axis([01-1000]);xlabel('归一化频率/\pi');ylabel('20log_{10}|W(e^{j\omega})|/dB');title(