音頻降噪Matlab仿真

1、數(shù)字信號(hào)處理大作業(yè)班級(jí)：1401012姓名：齊翔募學(xué)號(hào)入信號(hào)的時(shí)域波形及其功率譜密度:FileEditViewInsertToolsDesktopWindowHelp4|氫fj夔晶，2040600010012Q140160180200(Bp)4>pn=6BzEnlusdsSAAndo20-演波后的語音信號(hào)功率譜密度II:;1也£11.522.5FreRency"彳廣疊加噪聲后的音頻信號(hào)的時(shí)域圖形及功率譜密度:Figure2FileEditViewInsertTookDesktopWindowHelp口國'爭(zhēng)痘國|口國|篁20406。0

2、01001ZQ140160100200(山p)OJpn七匚6BZEnlusdsO20-加噪聲后的語音信號(hào)功率譜密度。石11.522.5Frequency*帚O經(jīng)過帶通濾波器的音頻信號(hào)的時(shí)域和功率譜密度:回回rnFileEditViewInsertToolsDesktopWindowHelp4|Wf?痘/|口留2-10120.0-O.Q語音信號(hào)時(shí)域波形20406060100120140160180200語音信號(hào)功率詣宵度O20-。石11.522.5F陪REncy*M程序解讀：clc;clearall;closeall;wav,fs=audioread('GDGvoice8000.wav&

3、#39;);t_end=1/fs*length(wav);%計(jì)算聲音的時(shí)間長(zhǎng)度Fs=50000;%仿真系統(tǒng)采樣率t=1/Fs:1/Fs:t_end;%仿真系統(tǒng)采樣時(shí)間點(diǎn)%利用插值函數(shù)將音頻信號(hào)的采樣率提升為Fs=50KHzwav=interp1(1/fs:1/fs:t_end,wav,t,'spline');%設(shè)計(jì)300Hz3400Hz的帶通預(yù)濾波器H(z)fenzi,fenmu=butter(6,3003400/(Fs/2);nt=wgn(1,length(t),0.1);%噪聲nt=nt/(max(abs(nt);%歸一化噪聲wav_noise=wav+nt;%對(duì)音頻信號(hào)進(jìn)

4、行濾波wav_after=filter(fenzi,fenmu,wav_noise);figure(1);subplot(2,1,1);plot(wav(53550:53750);title('語音信號(hào)時(shí)域波形,);axis(0200-0.30.3);subplot(2,1,2);psd(wav,10000,Fs);title('語音信號(hào)功率譜密度,);axis(025000-2010);figure(2);subplot(2,1,1);plot(wav_noise(53550:53750);title(,加噪聲后的語音信號(hào)時(shí)域波形,);axis(0200-0.30.3);su

5、bplot(2,1,2);psd(wav_noise,10000,Fs);title(,加噪聲后的語音信號(hào)功率譜密度,);axis(025000-2010);figure(3);subplot(2,1,1);plot(wav_after(53550:53750);title(,濾波后的語音信號(hào)時(shí)域波形,);axis(0200-0.30.3);subplot(2,1,2);psd(wav_after,10000,Fs);title(,濾波后的語音信號(hào)功率譜密度,);axis(025000-2010);sound(wav/max(wav),Fs);%播放解調(diào)音頻%播放解調(diào)音頻sound(wav_aft