實驗三fir濾波器的設計

實驗三IIR濾波器和FIR波器的設（一）IIR0.2pi，0.5pi，30db，T=10us。分別為切比濾波器和橢圓濾波器，采樣率Fs=20kHz，指標如下：0~4kHz，5kHz，Rp=0.5db，As=10db0~4kHz，5kHz，Rp=0.5db，As=10dbAs=10db。As=10db。functiondsp201()axis([01-1000])title('gridgridongridongridonfunctiondsp202()closeall;subplot(212);plot(w*fs/2/pi,abs(H2));grid;title(subplot(212);plot(w*fs/2/pi,abs(H2));grid;title(bw=wn(2)-subplot(211);plot(w*fs/2/pi,abs(H1));grid;title(subplot(212);plot(w*fs/2/pi,abs(H2));grid;title(subplot(211);plot(w*fs/2/pi,abs(H1));grid;title(plot(w*fs/2/pi,abs(H2));grid;title(由實驗結果可以看出：I型切近在通帶有等紋波的特性。II型切近在有理函數(shù)近。在兩近帶中均有等波紋特性。（二）FIR當N= 、、、 畫出其幅度響應H（w。用凱澤爾窗，窗，矩形窗設計具有指定指標的濾波器用頻率抽樣法設計一個理想低通濾波器，通帶截止頻率為0.375pi，阻帶截止頻率為functiondsp203()closeall;gridtitle('矩形窗函數(shù)法幅頻特性title('N=41');gridontitle('N=81');gridontitle('N=121');gridon%thefunctionfortheexperimentII(4)functiondsp204()closeall;title('rectanglewindows');gridontitle('kaiserwindows');gridontitle('hammingwindows');gridontitle('rectanglewindows');gridontitle('kaiserwindows');gridontitle('窗函數(shù)法設計高通濾波器hamminggridfunctiondsp205()closeall;a=(N-plot(w/pi,H1);gridon;%axis([010ylabel('title('a=(N-i=0:N-plot(w/pi,H1);gridon;%axis([010ylabel('title('a=(N-i=0:N-plot(w/pi,H1);gridon;%axis([010ylabel('title('FIR隨著MMRECTANGLEWINDOWS主瓣寬度較小、旁瓣寬度較小、旁瓣衰度較HAMMINGWINDOWS主瓣寬度較