MATLAB PROGRAM TO IMPLEMENT SAMPLING THEOREM for all Nyquist conditions

close all;

clear all;

t=-10:0.01:10;

T=8;

fm=1/T;

x=cos(2*pi*fm*t);

fs1=1.2*fm;

fs2=2*fm;

fs3=8*fm;

n1=-4:1:4;

xn1=cos(2*pi*n1*fm/fs1);

subplot(221)

plot(t,x);

xlabel('time in seconds');

ylabel('x(t)');

title('continous time signal');

subplot(222)

stem(n1,xn1);

hold on;

plot(n1,xn1);

xlabel('n');

ylabel('x(n)');

title('discrete time signal with fs<2fm');

%

n2=-5:1:5;

xn2=cos(2*pi*n2*fm/fs2);

subplot(223)

stem(n2,xn2);

hold on;

plot(n2,xn2);

xlabel('n');

ylabel('x(n)');

title('discrete time signal with fs=2fm');

%

n3=-20:1:20;

xn3=cos(2*pi*n3*fm/fs3);

subplot(224)

stem(n3,xn3);

hold on;

plot(n3,xn3);

xlabel('n');

ylabel('x(n)');

title('discrete time signal with fs>2fm');