AM调制解调过程仿真(共7页).docx

clcfs=1000;fc=20;fm=1;dt=0.001N=5/dt;t=0:N-1*dt;snr=1;g=5*cos(2*pi*fm*t);A=5;s_am=(A+g).*cos(2*pi*fc*t);figure(1);subplot(211);plot(g);grid on;df=fs/(N-1);f=(0:N-1)*df;yg=fft(g,N);mg=abs(yg(1:N/2)*2*pi/N;subplot(212);stem(f(1:20),mg(1:20);grid on;figure(2);subplot(211);plot(s_am);hold on; plot(A+g,r-);grid on;df=fs/(N-1);f=(0:N-1)*df;y=fft(s_am,N);m=abs(y(1:N/2)*2*pi/N;subplot(212);stem(f(1:200),m(1:200);grid on;figure