信号与系统仿真实验报告(7)

n1=0:14;

x=sin(0.4*n1); n2=0:19;

h=(0.9).^n2; L=10;%所取的长度为10 X=fft(x,L); H=fft(h,L); y=ifft(X.*H); figure(1); stem(x); grid on; figure(2); stem(h); gridon; figure(3); stem(y); grid on;

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当N=20时

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n1=0:14;

x=sin(0.4*n1); n2=0:19;

h=(0.9).^n2; L=20;%所取的长度为20 X=fft(x,L); H=fft(h,L); y=ifft(X.*H); figure(1); stem(x); grid on; figure(2); stem(h); grid on; figure(3); stem(y); grid on;

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取N=30时

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n1=0:14;

x=sin(0.4*n1); n2=0:19;

h=(0.9).^n2; L=30;%所取的长度为30 X=fft(x,L); H=fft(h,L); y=ifft(X.*H); figure(1); stem(x); grid on; figure(2); stem(h); grid on; figure(3); stem(y); grid on;

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