fs=22050; %sampling frequency Ts=1/fs; %sampling period N=1000; %number of samples t=[0:Ts:N*Ts-Ts]; %time axis f=[-fs/2:fs/N:fs/2-fs/N]; %frequency axis fc=2000; %carrier frequency fm=300; %modulation frequency p=sin(2*pi*fp*t); %carrier signal x=sin(2*pi*fm*t); %modulation signal m=0.75; %modulation index y=((1+m*x).*p); %modulated signal Y=fft(y); %modulated signal DFT figure() plot(t,y) ;title( 'AM Signal' );xlabel( 'Time axis' );ylabel( 'Amplitude' ); figure() stem(f,fftshift(abs(Y))) ;title( 'AM Signal Spectrum' );xlabel( 'Frequency axis' );ylabel( 'Amplitude' ); to run this program according to your requrement