数字信号处理Matlab操作实验报告实验一1.1实验要求指定一序列进行以下操作：补零、重复原序列本身，分别画出对应幅度谱1.2程序设计末尾补零法>>x=ones(1,16)x=Columns1through131111111111111Columns14through16111>>figure;stem(x)>>y=[ones(1,16),zeros(1,16)]y=Columns1through131111111111111Columns14through261110000000000Columns27through32000000>>figure;stem(y)>>y=fft(x,32);>>figure;stem(abs(y))重复原序列本身>>x=ones(1,16);>>figure;stem(x)>>y=fft(x,32)y=Columns1through416.00001.0000-10.1532i01.0000-3.2966iColumns5through801.0000-1.8709i01.0000-1.2185iColumns9through1201.0000-0.8207i01.0000-0.5345iColumns13through1601.0000-0.3033i01.0000-0.0985iColumns17through2001.0000+0.0985i01.0000+0.3033iColumns21through2401.0000+0.5345i01.0000+0.8207iColumns25through2801.0000+1.2185i01.0000+1.8709iColumns29through3201.0000+3.2966i01.0000+10.1532i>>figure;stem(y)>>figure;stem(abs(y))实验二2.1实验要求设计一个巴特沃斯型和切比雪夫Ⅰ型数字低通滤波器，把提取出来，要求通带衰减小于1dB，阻带衰减大于15dB。画出所设计DF的频响，分析滤波前后信号的频谱2.2实验设计巴特沃斯型设置通带截止频率fc=35Hz,，阻带的起始频率fs=40Hz.>>Fs=500;>>T=1/Fs;>>fc=35;>>fs=50;>>wc=fc*2*pi*T;>>ws=fs*2*pi*T;>>Wc=wc/pi;>>Ws=ws/pi;>>[N,W]=buttord(Wc,Ws,1,15)N=7W=0.1586>>[b,a]=butter(N,W)b=1.0e-003*Columns1through70.02220.15550.46640.77730.77730.46640.1555Column80.0222a=Columns1through71.0000-4.76359.9850-11.87888.6336-3.82450.9543Column8-0.1033>>y=freqz(b,a);>>f=0:Fs/2/512:Fs/2-Fs/2/512;>>plot(f,abs(y))切比雪夫I型滤波器设置通带截止频率fc=40Hz,，阻带的起始频率fs=50Hz.>>Fs=500;>>T=1/Fs;>>fc=40;>>fs=50;>>wc=fc*2*pi*T;>>ws=fs*2*pi*T;>>Wc=wc/pi;>>Ws=ws/pi;>>[N,W]=cheb1ord(Wc,Ws,1,15)N=5W=0.1600>>[b,a]=cheby1(N,1,W)b=1.0e-003*0.10000.49980.99970.99970.49980.1000a=1.0000-4.23647.4629-6.80733.2088-0.6249>>y=freqz(b,a);>>f=0:Fs/2/512:Fs/2-Fs/2/512;>>plot(f,abs(y))2.3实验分析最初波形(从上至下，分别对应,,以及)>>f1=10;>>f2=100;>>Fs=500;>>t=(1:500)/Fs;>>x1=cos(2*pi*f1*t);>>x2=cos(2*pi*f2*t);>>x=x1+x2;>>subplot(2,2,1);t=(1:500)/Fs;plot(t,x1);>>subplot(2,2,2);t=(1:500)/Fs;pl