%matlab code for digital modulation(ask, fsk and psk)
pi=3.14;
f=5;
f2=10;
phi=pi;
x=[1 0 1 1 0];
nx=size(x,2);
i=1;
while i<nx+1
t = i:0.001:i+1;
if x(i)==1
ask=sin(2*pi*f*t);
fsk=sin(2*pi*f*t);
psk=sin(2*pi*f*t);
else
ask=0;
fsk=sin(2*pi*f2*t);
psk=sin(2*pi*f*t+phi);
end
subplot(3,1,1);
plot(t,ask);
hold on;
grid on;
axis([1 10 -2 2]);
subplot(3,1,2);
plot(t,fsk);
hold on;
grid on;
axis([1 10 -2 2]);
subplot(3,1,3);
plot(t,psk);
hold on;
grid on;
axis([1 10 -2 2]);
i=i+1;
end
