h.m

信号与系统课程设计全部内容

Fm=10;
Fc=100;
Fs=1000;
N=1000;
k=0:N-1;
t=k/Fs;
x=sin(2.0*pi*Fm*t);
subplot(3,2,1);
plot(t(1:200),x(1:200));
axis([0,0.2,-1,1]);
Xf=abs(fft(x,N));
subplot(3,2,2);
stem(Xf(1:200));
y=modulate(x,Fc,Fs,'am');
subplot(3,2,3);
plot(t(1:200),y(1:200));
axis([0,0.2,-1,1]);
Xf=abs(fft(y,N));
subplot(3,2,4);stem(Xf(1:200));
z=modulate(y,Fc,Fs,'am');
subplot(3,2,5);
plot(t(1:200),z(1:200));
axis([0,0.2,-1,1]);
Xf=abs(fft(y,N));
subplot(3,2,6);stem(Xf(1:200));