Amplitude Modulation signal using MATLAB

                                                                     THEORY

In amplitude modulation, the amplitude (signal strength) of the carrier wave is varied in proportion to that of the message signal, such as an audio signal. Modulation is the process of converting data into electrical signals optimized for transmission.

                                                                 MATLAB Code:

fm = 1000;

fc =100*10^6;

Mp = 1;

Mu=1.5;

Ac = Mp/Mu;

Tm = 1/fm;

Tc = 1/fc;

t = 0:Tm/999:6*Tm;

%message signal plot

modulating_signal = Mp*sin(2*pi*fm*t);

subplot(3,1,1)

plot(t, modulating_signal);

grid on;

title('modulating signal');

xlabel=('time(sec)');

ylabel=('voltage(V)');

%carrier signal plot

carrier_signal = Ac*sin(2*pi*fc*t);

subplot(3,1,2)

plot(t, carrier_signal);

grid on;

title('Carrier Signal');

xlabel=('time(sec)');

ylabel=('voltage(V)');

%modulated signal plot

Y= (modulating_signal+Ac).*sin(2*pi*fc*t);

subplot(3,1,3)

plot(t,Y);

grid on;

title('Amplitude modulated signal');

xlabel=('time(sec)');

ylabel=('voltage(V)');

Conclusion:

On increasing value of Mu, Signal distorts and baseband signal is not received in envelope.