Natural Sampling by Square Wave

Matlab program for Natural Sampling by Square Wave.

Matlab code

clc; close all; clear all;

fm=input('Enter the frequency of Message signal = ');

fc=input('Enter the frequency of Carrier signal = ');

A=input('Enter the amplitude of Message signal = ');

t = 0:0.0001:1/fm;

Sm=A*sin(2*pi*fm*t); % Message signal

Ssq=square(2*pi*fc*t); % Carrier signal (Square Wave)

% Conversion of Square Wave to Pulse train Sp

for i=1:length(Ssq)

    if(Ssq(i)<=0)

        Sp(i)=0;

    else

        Sp(i)=1;

    end

end

Sn=Sp.*Sm; % Natural Sampled Signal

subplot(4,1,1);

plot(t,Sm);

xlabel('Time-->');

ylabel('Amplitude-->');

title('Message Signal');

subplot(4,1,2);

plot(t,Ssq);

xlabel('Time-->');

ylabel('Amplitude-->');

title('Square wave');

axis([0 1/fm -A-1 A+1]);

subplot(4,1,3);

plot(t,Sp);

xlabel('Time-->');

ylabel('Amplitude-->');

title('Carrier Signal');

axis([0 1/fm -A-1 A+1]);

subplot(4,1,4);

plot(t,Sn);

xlabel('Time-->');

ylabel('Amplitude-->');

title('Natural Sampled Signal');

Command window

Enter the frequency of Message signal = 2

Enter the frequency of Carrier signal = 100

Enter the amplitude of Message signal = 1

Figure window