數(shù)字信號(hào)處理課程設(shè)計(jì)報(bào)告

1、數(shù)字信號(hào)處理課程設(shè)計(jì)實(shí)驗(yàn)報(bào)告一、 課程設(shè)計(jì)內(nèi)容要求1、課程設(shè)計(jì)題目設(shè)計(jì)并實(shí)現(xiàn)一個(gè)流程如圖所示的信號(hào)處理演示系統(tǒng)，該系統(tǒng)包含信號(hào)發(fā)生器、頻譜分析、濾波器設(shè)計(jì)、數(shù)字濾波和輸出信號(hào)分析5個(gè)主要模塊，各模塊的具體功能要求如下：1) 信號(hào)發(fā)生器根據(jù)信號(hào)類型不同可分為兩大類：（1） 靜態(tài)型：直接輸入測(cè)試信號(hào)系列。（2） 動(dòng)態(tài)型：輸入如下式所示的由多個(gè)不同頻率正弦信號(hào)疊加組合而成的模擬信號(hào)公式，指定采樣頻率和采樣點(diǎn)數(shù)，動(dòng)態(tài)生成該信號(hào)的采樣序列，作為測(cè)試信號(hào)。100sin（2pif1t）+100sin(2pif2t)+100sin(2pifnt)2) 頻譜分析是用FFT對(duì)產(chǎn)生的測(cè)試信號(hào)進(jìn)行頻域變換，展示其幅頻

2、、相頻特性，指定需要濾出或保留的頻帶，通過選擇濾波器類型（IIR或FIR），確定對(duì)應(yīng)的濾波器技術(shù)指標(biāo)（低通、高通、帶通、帶阻）。3) 濾波器設(shè)計(jì) 根據(jù)IIR/FIR數(shù)字濾波器技術(shù)指標(biāo)設(shè)計(jì)濾波器，生成相應(yīng)的濾波器系數(shù)，并展示對(duì)應(yīng)的濾波器幅頻、相頻特性。(1) IIR DF設(shè)計(jì)：使用雙線性變換法，可選擇濾波器類型（巴特沃斯/切比雪夫型）；(2) FIR DF 設(shè)計(jì)：使用窗口法，可選擇窗口類型。4) 數(shù)字濾波根據(jù)設(shè)計(jì)的濾波器系數(shù)，對(duì)測(cè)試信號(hào)進(jìn)行濾波，得到濾波后信號(hào)。（1） IIR DF：要求通過差分方程迭代實(shí)現(xiàn)濾波，未知初值置0處理；（2） FIR DF：要求通過快速卷積實(shí)現(xiàn)濾波，可以選擇使用重疊相

3、加或重疊保留法進(jìn)行卷積運(yùn)算，并動(dòng)態(tài)展示卷積運(yùn)算的詳細(xì)過程。5) 輸出信號(hào)分析展示濾波后信號(hào)的幅頻和相頻特性，分析是否滿足濾波要求。對(duì)同一濾波要求，根據(jù)輸出信號(hào)頻譜，對(duì)比分析各類濾波器的差異。2、設(shè)計(jì)題目要求使用MATLAB編程實(shí)現(xiàn)上述信號(hào)處理演示系統(tǒng)，具體要求如下：（1）系統(tǒng)應(yīng)使用圖形用戶界面（GUI）；（2）系統(tǒng)功能至少包括非語(yǔ)音信號(hào)的低通和高通濾波；（3）濾波器設(shè)計(jì)模塊應(yīng)避免使用MATLAB工具箱函數(shù)；（4）IIR DF設(shè)計(jì)必須可選基于巴特沃斯或切比雪夫1型；（5）FIR DF設(shè)計(jì)必須可選擇各類窗口，且FIR濾波可選長(zhǎng)序列卷積方法。二、設(shè)計(jì)思想和系統(tǒng)功能結(jié)構(gòu)及功能說明1.設(shè)計(jì)思想 信號(hào)處理

4、演示系統(tǒng)的原理是，首先通過信號(hào)發(fā)生器產(chǎn)生測(cè)試信號(hào)，然后對(duì)它進(jìn)行頻譜分析，接下來設(shè)置濾波器技術(shù)指標(biāo)，然后選擇濾波器類型進(jìn)行數(shù)字濾波，最后輸出濾波后的信號(hào)，并對(duì)它進(jìn)行頻譜分析。因此，實(shí)現(xiàn)系統(tǒng)的方法如下：首先，利用MATLAB進(jìn)行GUI設(shè)計(jì)，用來實(shí)現(xiàn)系統(tǒng)用戶界面的操作。GUI界面包括：輸入信號(hào)部分（輸入信號(hào)設(shè)置部分，輸入信號(hào)幅頻、相頻特性顯示部分），濾波器部分（濾波器類型選擇部分，濾波器窗口選擇部分，濾波器技術(shù)指標(biāo)設(shè)置部分，濾波器幅頻、相頻特性顯示部分），輸出信號(hào)部分（輸出信號(hào)幅頻、相頻特性顯示部分）。然后，對(duì)GUI界面的每個(gè)控件，編寫對(duì)應(yīng)的callback函數(shù)，使其完成相應(yīng)的操作，如數(shù)據(jù)傳遞或者濾

5、波器濾波以及展示所需的特性曲線顯。2.系統(tǒng)功能說明結(jié)構(gòu)及功能對(duì)輸入的模擬信號(hào)進(jìn)行采樣變成數(shù)字信號(hào)，然后對(duì)其進(jìn)行頻譜分析，輸出相應(yīng)的幅頻、相頻特性曲線。然后設(shè)置濾波器技術(shù)指標(biāo)，選擇濾波器類型，進(jìn)行濾波，同時(shí)輸出濾波器的幅頻、相頻特性曲線，還有濾波后的信號(hào)的幅頻、相頻特性曲線。濾波器類型分為IIR和FIR數(shù)字濾波器：在IIR DF中，可選擇濾波器類型為：巴特沃斯/切比雪夫1型，對(duì)應(yīng)的濾波器有高通或低通濾波器。在FIR DF中，用窗口法，可選擇窗口類型為：漢寧窗，哈明窗，三角形窗，矩形窗，凱塞窗，布萊克曼窗，對(duì)應(yīng)的濾波器有高通或低通濾波器。三、 系統(tǒng)設(shè)計(jì)詳情（1）輸入信號(hào)部分設(shè)計(jì)1. 信號(hào)發(fā)生器設(shè)計(jì)

6、：采用動(dòng)態(tài)型信號(hào)發(fā)生器設(shè)計(jì)方法，先輸入三個(gè)頻率f1，f2，f3，然后由這三個(gè)不同頻率的正弦信號(hào)疊加組合成模擬信號(hào)，再輸入采樣頻率f以及采樣點(diǎn)數(shù)cyds，動(dòng)態(tài)生成該信號(hào)的采樣序列，作為測(cè)試信號(hào)。GUI界面信號(hào)輸入部分設(shè)計(jì)如下圖：頻率1的callback為：global f1f1=str2num(get(hObject,'string');其他的callback類似。生成的模擬信號(hào)為：x=100*sin(2*pi*f1*t)+100*sin(2*pi*f2*t)+100*sin(2*pi*f3*t);采樣頻率的callback為： global f f=str2num(get(hO

7、bject,'string');采樣后的輸入信號(hào)為：y=100*sin(2*pi*f1/f*n)+100*sin(2*pi*f2/f*n)+100*sin(2*pi*f3/f*n);2. 輸入信號(hào)頻譜分析設(shè)計(jì)：是用FFT對(duì)產(chǎn)生的測(cè)試信號(hào)進(jìn)行頻域變換，展示其幅頻、相頻特性。wk=2/cyds*(0:cyds-1);subplot(4,3,1); stem(wk,abs(fft(y),'.'); axis(0 1 0 inf); subplot(4,3,4); stem(wk,angle(fft(y),'.'); axis(0,0.1,-5,5)當(dāng)f

8、1=200，f2=400，f3=800，f=2000，cyds=1000時(shí)：輸入信號(hào)的幅頻、相頻特性曲線如下：（2）濾波器設(shè)計(jì)部分：1.濾波器技術(shù)指標(biāo)設(shè)計(jì)： GUI界面濾波器技術(shù)指標(biāo)設(shè)置部分設(shè)計(jì)如下圖：IIR型濾波器的技術(shù)指標(biāo)有：通帶最大衰減ap，阻帶最小衰減as，通帶截止頻率fp，阻帶截止頻率fs。FIR型濾波器的技術(shù)指標(biāo)有：通帶截止頻率fp，阻帶截止頻率fs。通帶最大衰減ap的callback為：global apap=str2num(get(hObject,'string');其他的callback類似。2濾波器類型設(shè)計(jì)：（1）IIR濾波器選擇界面設(shè)計(jì)：低通巴特沃斯濾波器

9、的callback為：global asglobal apglobal fsglobal fpglobal y T=1 wp=pi*fp; ws=pi*fs; wp1=2*tan(wp/2); ws1=2*tan(ws/2); N,wc=buttord(wp1,ws1,ap,as,'s'); B,A=butter(N,wc,'s'); b,a=bilinear(B,A,1/T); h,w=freqz(b,a,512,'whole');subplot(4,3,2); plot(w/pi,abs(h); axis(0,1,0,1); subplot(

10、4,3,5); plot(0.5*w/pi,angle(h); z=filter(b,a,y); ft,Wt=freqz(z,512); subplot(4,3,3); plot(Wt/pi,abs(ft); subplot(4,3,6); plot(Wt/pi,angle(ft);高通巴特沃斯濾波器的callback為：只要把上面的B,A=butter(N,wc,'s');改為B,A=butter(N,wc,'high','s');即可。切比雪夫低通濾波器的callback為：global asglobal apglobal fsglobal

11、fpglobal y T=1 wp=pi*fp; ws=pi*fs; wp1=2*tan(wp/2); ws1=2*tan(ws/2); N,wp=cheb1ord(wp1,ws1,ap,as,'s'); B,A=cheby1(N,ap,wp,'s'); b,a=bilinear(B,A,1/T); h,w=freqz(b,a,512,'whole'); subplot(4,3,2); plot(w/pi,abs(h); axis(0,1,0,1); subplot(4,3,5); plot(0.5*w/pi,angle(h); z=filter

12、(b,a,y); ft,Wt=freqz(z,512); subplot(4,3,3); plot(Wt/pi,abs(ft); subplot(4,3,6); plot(Wt/pi,angle(ft);切比雪夫高通濾波器的callback為：只要把上面的B,A=cheby1(N,ap,wp,'s');改為B,A=cheby1(N,ap,wp,high，'s');即可（2）FIR濾波器選擇界面設(shè)計(jì)：漢寧窗低通濾波器的callback為：global asglobal apglobal fsglobal fpglobal y wp=pi*fp; ws=pi*fs;

13、 Bt=ws-wp; N0=ceil(6.2*pi/Bt); N=N0+mod(N0+1,2); wc=(wp+ws)/2/pi; hn=fir1(N-1,wc,hanning(N); h1,w1=freqz(hn,1); subplot(4,3,2); plot(w1/pi,20*log10(abs(h1);grid on axis(0,1,-80,5) subplot(4,3,5); plot(w1/pi,20*log10(angle(h1);grid on h=conv(y,hn); ft,Wt=freqz(h,512); subplot(4,3,3); plot(Wt/pi,abs(f

14、t); subplot(4,3,6); plot(Wt/pi,angle(ft);漢寧窗高通濾波器的callback為：只要把hn=fir1(N-1,wc,hanning(N);改為hn=fir1(N-1,wc,'high',hanning(N); 即可其他窗函數(shù)只要改變此句（hn=fir1(N-1,wc,hanning(N);）里的窗口類型和ftype即可。這6種窗函數(shù)的產(chǎn)生函數(shù)和調(diào)用格式為：矩形窗: wn=boxcar(N)三角窗函數(shù)： wn=bartlett（N）漢寧窗函數(shù)： wn=hanning（N）哈明窗函數(shù)： wn=hamming（N）布萊克曼窗函數(shù)： wn=bla

15、ckman（N）凱塞窗函數(shù)： wn=kaiser（N）3. 濾波器頻譜分析設(shè)計(jì)： GUI界面濾波器的幅頻、相頻特性曲線輸出部分設(shè)計(jì)如下圖：當(dāng)ap=3，as=30，fp=0.1，fs=0.3時(shí)：（1）巴特沃斯低通濾波器的頻譜分析為：（2）切比雪夫低通濾波器的頻譜分析為：當(dāng)ap=3，as=30，fp=0.3，fs=0.1時(shí)：（1）巴特沃斯高通濾波器的頻譜分析為：（2）切比雪夫高通濾波器的頻譜分析為：當(dāng)fp=0.1，fs=0.3時(shí)：（1）漢寧窗低通濾波器的頻譜分析如下：（2）哈明窗低通濾波器的頻譜分析如下：（3）矩形窗低通濾波器的頻譜分析如下：（4）凱塞窗低通濾波器的頻譜分析如下：（5）三角窗低通濾

16、波器的頻譜分析如下：（6）布萊克曼窗低通濾波器的頻譜分析如下：當(dāng)fp=0.3，fs=0.1時(shí)：（1）漢寧窗高通濾波器的頻譜分析如下：（2）哈明窗高通濾波器的頻譜分析如下：（3）矩形窗高通濾波器的頻譜分析如下：（4）凱塞窗高通濾波器的頻譜分析如下：（5）三角窗高通濾波器的頻譜分析如下：（6）布萊克曼窗高通濾波器的頻譜分析如下：四、 測(cè)試信號(hào)濾波后輸出部分設(shè)計(jì)：GUI界面輸出信號(hào)的幅頻、相頻特性曲線設(shè)計(jì)如下圖：（1）當(dāng)f1=200，f2=400，f3=800，f=2000，cyds=1000，ap=3，as=30，fp=0.1，fp=0.3時(shí)：輸出信號(hào)的幅頻特性曲線和輸入信號(hào)的幅頻特性曲線對(duì)比可得

17、：經(jīng)過巴特沃斯低通濾波器濾波后，輸出信號(hào)的幅頻、相頻特性曲線如下圖：0.4和0.8被濾除，只剩下0.2。經(jīng)過切比雪夫低通濾波器濾波后，輸出信號(hào)的幅頻、相頻特性曲線如下圖：（2）當(dāng)f1=200，f2=400，f3=800，f=2000，cyds=1000，ap=3，as=30，fp=0.6，fp=0.5時(shí)：輸出信號(hào)的幅頻特性曲線和輸入信號(hào)的幅頻特性曲線對(duì)比可得：經(jīng)過巴特沃斯高通濾波器濾波后，輸出信號(hào)的幅頻、相頻特性曲線如下圖：0.2和0.4被濾除，只剩下0.8。經(jīng)過切比雪夫高通濾波器濾波后，輸出信號(hào)的幅頻、相頻特性曲線如下圖：（3）當(dāng)f1=200，f2=400，f3=800，f=2000，cyd

18、s=1000， fp=0.1，fp=0.3時(shí)：經(jīng)過漢寧窗低通濾波器濾波后，輸出信號(hào)的幅頻、相頻特性曲線如下圖：0.8和0.4被濾除，只剩下0.2。（4）當(dāng)f1=200，f2=400，f3=800，f=2000，cyds=1000， fp=0.6，fp=0.5時(shí)：經(jīng)過哈明窗高通濾波器濾波后，輸出信號(hào)的幅頻、相頻特性曲線如下圖：0.2和0.4被濾除，只剩下0.8。其他窗函數(shù)濾波后的情況與以上情況類似。GUI界面整體圖設(shè)計(jì)如下圖：四、課程設(shè)計(jì)總結(jié)五、 參考文獻(xiàn)丁玉梅等.數(shù)字信號(hào)處理.西安：西安電子科技大學(xué)出版社，2002.六、 源代碼清單function varargout = GUI(vararg

19、in)gui_Singleton = 1;gui_State = struct('gui_Name', mfilename, . 'gui_Singleton', gui_Singleton, . 'gui_OpeningFcn', GUI_OpeningFcn, . 'gui_OutputFcn', GUI_OutputFcn, . 'gui_LayoutFcn', , . 'gui_Callback', );if nargin && ischar(varargin1) gui_S

20、tate.gui_Callback = str2func(varargin1);endif nargout varargout1:nargout = gui_mainfcn(gui_State, varargin:);else gui_mainfcn(gui_State, varargin:);endfunction GUI_OpeningFcn(hObject, eventdata, handles, varargin)handles.output = hObject;guidata(hObject, handles);function varargout = GUI_OutputFcn(h

21、Object, eventdata, handles) varargout1 = handles.output;function edit16_Callback(hObject, eventdata, handles) global fp fp=str2num(get(hObject,'string')function edit18_Callback(hObject, eventdata, handles) global fs fs=str2num(get(hObject,'string');function edit18_CreateFcn(hObject,

22、eventdata, handles) global ap ap=str2num(get(hObject,'string');function edit20_Callback(hObject, eventdata, handles) global as as=str2num(get(hObject,'string');function edit23_Callback(hObject, eventdata, handles) global cyds cyds=str2num(get(hObject,'string');function edit24

23、_Callback(hObject, eventdata, handles) global f f=str2num(get(hObject,'string');function edit25_Callback(hObject, eventdata, handles) global f1 f1=str2num(get(hObject,'string');function edit27_Callback(hObject, eventdata, handles) global f2 f2=str2num(get(hObject,'string');fu

24、nction edit28_Callback(hObject, eventdata, handles) global f3 f3=str2num(get(hObject,'string');function edit28_CreateFcn(hObject, eventdata, handles)function pushbutton10_Callback(hObject, eventdata, handles)global asglobal apglobal fsglobal fpglobal y T=1 wp=pi*fp; ws=pi*fs; wp1=2*tan(wp/2)

25、; ws1=2*tan(ws/2); N,wc=buttord(wp1,ws1,ap,as,'s'); B,A=butter(N,wc,'s'); b,a=bilinear(B,A,1/T); h,w=freqz(b,a,512,'whole'); subplot(4,3,2); plot(w/pi,abs(h); axis(0,1,0,1); subplot(4,3,5); plot(0.5*w/pi,angle(h); z=filter(b,a,y); ft,Wt=freqz(z,512); subplot(4,3,3); plot(Wt/p

26、i,abs(ft); subplot(4,3,6); plot(Wt/pi,angle(ft);function pushbutton11_Callback(hObject, eventdata, handles)global asglobal apglobal fsglobal fpglobal y T=1 wp=pi*fp; ws=pi*fs; wp1=2*tan(wp/2); ws1=2*tan(ws/2); N,wp=cheb1ord(wp1,ws1,ap,as,'s'); B,A=cheby1(N,ap,wp,'s'); b,a=bilinear(B,

27、A,1/T); h,w=freqz(b,a,512,'whole'); subplot(4,3,2); plot(w/pi,abs(h); axis(0,1,0,1); subplot(4,3,5); plot(0.5*w/pi,angle(h); z=filter(b,a,y); ft,Wt=freqz(z,512); subplot(4,3,3); plot(Wt/pi,abs(ft); subplot(4,3,6); plot(Wt/pi,angle(ft); function pushbutton12_Callback(hObject, eventdata, handl

28、es)global asglobal apglobal fsglobal fpglobal y wp=pi*fp; ws=pi*fs; Bt=wp-ws; N0=ceil(6.2*pi/Bt); N=N0+mod(N0+1,2); wc=(wp+ws)/2/pi; hn=fir1(N-1,wc,'high',hanning(N); h1,w1=freqz(hn,1); subplot(4,3,2); plot(w1/pi,20*log10(abs(h1);grid onaxis(0,1,-80,5) subplot(4,3,5); plot(w1/pi,20*log10(ang

29、le(h1);grid on h=conv(y,hn); ft,Wt=freqz(h,512); subplot(4,3,3); plot(Wt/pi,abs(ft); subplot(4,3,6); plot(Wt/pi,angle(ft);function pushbutton13_Callback(hObject, eventdata, handles)global asglobal apglobal fsglobal fpglobal y wp=pi*fp; ws=pi*fs; Bt=ws-wp; N0=ceil(6.2*pi/Bt); N=N0+mod(N0+1,2); wc=(wp

30、+ws)/2/pi; hn=fir1(N-1,wc,bartlett(N); h1,w1=freqz(hn,1); subplot(4,3,2); plot(w1/pi,20*log10(abs(h1);grid onaxis(0,1,-80,5) subplot(4,3,5); plot(w1/pi,20*log10(angle(h1);grid on h=conv(y,hn); ft,Wt=freqz(h,512); subplot(4,3,3); plot(Wt/pi,abs(ft); subplot(4,3,6); plot(Wt/pi,angle(ft);function pushb

31、utton14_Callback(hObject, eventdata, handles)global asglobal apglobal fsglobal fpglobal y wp=pi*fp; ws=pi*fs; Bt=ws-wp; N0=ceil(6.2*pi/Bt); N=N0+mod(N0+1,2); wc=(wp+ws)/2/pi; hn=fir1(N-1,wc,hamming(N); h1,w1=freqz(hn,1); subplot(4,3,2); plot(w1/pi,20*log10(abs(h1);grid onaxis(0,1,-80,5) subplot(4,3,

32、5); plot(w1/pi,20*log10(angle(h1);grid on h=conv(y,hn); ft,Wt=freqz(h,512); subplot(4,3,3); plot(Wt/pi,abs(ft); subplot(4,3,6); plot(Wt/pi,angle(ft);function pushbutton15_Callback(hObject, eventdata, handles)global asglobal apglobal fsglobal fpglobal y wp=pi*fp; ws=pi*fs; Bt=ws-wp; N0=ceil(6.2*pi/Bt

33、); N=N0+mod(N0+1,2); wc=(wp+ws)/2/pi; hn=fir1(N-1,wc,kaiser(N); h1,w1=freqz(hn,1); subplot(4,3,2); plot(w1/pi,20*log10(abs(h1);grid onaxis(0,1,-80,5) subplot(4,3,5); plot(w1/pi,20*log10(angle(h1);grid on h=conv(y,hn); ft,Wt=freqz(h,512); subplot(4,3,3); plot(Wt/pi,abs(ft); subplot(4,3,6); plot(Wt/pi

34、,angle(ft);function pushbutton16_Callback(hObject, eventdata, handles)global asglobal apglobal fsglobal fpglobal y wp=pi*fp; ws=pi*fs; Bt=ws-wp; N0=ceil(6.2*pi/Bt); N=N0+mod(N0+1,2); wc=(wp+ws)/2/pi; hn=fir1(N-1,wc,boxcar(N); h1,w1=freqz(hn,1); subplot(4,3,2); plot(w1/pi,20*log10(abs(h1);grid onaxis

35、(0,1,-80,5) subplot(4,3,5); plot(w1/pi,20*log10(angle(h1);grid on h=conv(y,hn); ft,Wt=freqz(h,512); subplot(4,3,3); plot(Wt/pi,abs(ft); subplot(4,3,6); plot(Wt/pi,angle(ft);function pushbutton17_Callback(hObject, eventdata, handles)global asglobal apglobal fsglobal fpglobal y wp=pi*fp; ws=pi*fs; Bt=

36、ws-wp; N0=ceil(6.2*pi/Bt); N=N0+mod(N0+1,2); wc=(wp+ws)/2/pi; hn=fir1(N-1,wc,blackman(N); h1,w1=freqz(hn,1); subplot(4,3,2); plot(w1/pi,20*log10(abs(h1);grid onaxis(0,1,-80,5) subplot(4,3,5); plot(w1/pi,20*log10(angle(h1);grid on h=conv(y,hn); ft,Wt=freqz(h,512); subplot(4,3,3); plot(Wt/pi,abs(ft);

37、subplot(4,3,6); plot(Wt/pi,angle(ft);function pushbutton18_Callback(hObject, eventdata, handles) global y global f1 global f2 global f3 global f global cyds t=0:0.0001:1; x=100*sin(2*pi*f1*t)+100*sin(2*pi*f2*t)+100*sin(2*pi*f3*t); n=0:cyds-1; y=100*sin(2*pi*f1/f*n)+100*sin(2*pi*f2/f*n)+100*sin(2*pi*

38、f3/f*n); wk=2/cyds*(0:cyds-1); subplot(4,3,1); stem(wk,abs(fft(y),'.'); axis(0 1 0 inf); subplot(4,3,4); stem(wk,angle(fft(y),'.'); axis(0,0.1,-5,5)function pushbutton19_Callback(hObject, eventdata, handles)global asglobal apglobal fsglobal fpglobal y T=1 wp=pi*fp; ws=pi*fs; wp1=2*ta

39、n(wp/2); ws1=2*tan(ws/2); N,wc=buttord(wp1,ws1,ap,as,'s'); B,A=butter(N,wc,'high','s'); b,a=bilinear(B,A,1/T); h,w=freqz(b,a,512,'whole'); subplot(4,3,2); plot(w/pi,abs(h); axis(0,1,0,1); subplot(4,3,5); plot(0.5*w/pi,angle(h); z=filter(b,a,y); ft,Wt=freqz(z,512); sub

40、plot(4,3,3); plot(Wt/pi,abs(ft); subplot(4,3,6); plot(Wt/pi,angle(ft); function pushbutton20_Callback(hObject, eventdata, handles)global asglobal apglobal fsglobal fpglobal y T=1 wp=pi*fp; ws=pi*fs; wp1=2*tan(wp/2); ws1=2*tan(ws/2); N,wp=cheb1ord(wp1,ws1,ap,as,'s'); B,A=cheby1(N,ap,wp,'h

41、igh','s'); b,a=bilinear(B,A,1/T); h,w=freqz(b,a,512,'whole'); subplot(4,3,2); plot(w/pi,abs(h); axis(0,1,0,1); subplot(4,3,5); plot(0.5*w/pi,angle(h); z=filter(b,a,y); ft,Wt=freqz(z,512); subplot(4,3,3); plot(Wt/pi,abs(ft); subplot(4,3,6); plot(Wt/pi,angle(ft); function pushbutto

42、n21_Callback(hObject, eventdata, handles)global asglobal apglobal fsglobal fpglobal y wp=pi*fp; ws=pi*fs; Bt=ws-wp; N0=ceil(6.2*pi/Bt); N=N0+mod(N0+1,2); wc=(wp+ws)/2/pi; hn=fir1(N-1,wc,hanning(N); h1,w1=freqz(hn,1); subplot(4,3,2); plot(w1/pi,20*log10(abs(h1);grid on axis(0,1,-80,5) subplot(4,3,5);

43、 plot(w1/pi,20*log10(angle(h1);grid on h=conv(y,hn); ft,Wt=freqz(h,512); subplot(4,3,3); plot(Wt/pi,abs(ft); subplot(4,3,6); plot(Wt/pi,angle(ft);function pushbutton22_Callback(hObject, eventdata, handles)global asglobal apglobal fsglobal fpglobal y wp=pi*fp; ws=pi*fs; Bt=wp-ws; N0=ceil(6.2*pi/Bt);

44、N=N0+mod(N0+1,2); wc=(wp+ws)/2/pi; hn=fir1(N-1,wc,'high',hamming(N); h1,w1=freqz(hn,1); subplot(4,3,2); plot(w1/pi,20*log10(abs(h1);grid onaxis(0,1,-80,5) subplot(4,3,5); plot(w1/pi,20*log10(angle(h1);grid on h=conv(y,hn); ft,Wt=freqz(h,512); subplot(4,3,3); plot(Wt/pi,abs(ft); subplot(4,3,6

45、); plot(Wt/pi,angle(ft);function pushbutton23_Callback(hObject, eventdata, handles)global asglobal apglobal fsglobal fpglobal y wp=pi*fp; ws=pi*fs; Bt=wp-ws; N0=ceil(6.2*pi/Bt); N=N0+mod(N0+1,2); wc=(wp+ws)/2/pi; hn=fir1(N-1,wc,'high',kaiser(N); h1,w1=freqz(hn,1); subplot(4,3,2); plot(w1/pi,20*log10(abs(h1);grid onaxis(0,1,-80,5) subplot(4,3,5); plot(w1/pi,20*log10(angle(h1);grid on h=conv(y,hn); ft,Wt=f