am.m

AM调制及单边带调制 程序规范易懂,It will be helpful to you!

%Amplitude modulation - Single Tone Modulation - DSB-SC, DSB-AM

% Saurav R Tuladhar  059BEX438/DOECE/PC/IOE

 clear;
 Ac = 1;  % Carrier Amplitude
 Am = 1;  % Baseband Amplitude
 fc = 200; %
 fm = 20;
 m  = Am/Ac; 

 t = linspace(0,1,100*fc);            

%e = Ac*Am*cos(2*pi*fm*t);           
 e = (Ac + Am*cos(2*pi*fm*t));         %DSB-AM envelop

%u = (Ac*Am*cos(2*pi*fm*t).*cos(2*pi*fc*t));   %DSB-SC
 u = (Ac + Am*cos(2*pi*fm*t)).*cos(2*pi*fc*t); %DSB-AM

 hold on;
 %grid on;
 plot(t,u);
 plot(t,e,'r');
 plot(t,-e,'r');
 hold off;
 title('Amplitude Modulation');
 xlabel('Time');
 ylabel('u(t)');