Modulated Wave
Amplitude modulation (AM) is a technique used in electronic communication, most commonly for transmitting information via a radio carrier wave. AM works by varying the strength of the transmitted signal in relation to the information being sent.
Let you check the propagation of AM wave in MATLAB.
k = 10;
w = 5;
dx = 0.05;
x = 0:dx:40;
dt = 0.05;
t = 1:dt:10;
A = 5;
for j=1:length(t)
for i=1:length(x)
y(i) = A * sin(50*k.* x(i)).* cos(50*w.*t(j)).*sin(k.* x(i)).* cos(w.* t(j));
y(i) = A * sin(k.* x(i) - w.*t(j)).*cos(k.* x(i) - w.*t(j)).*sin(50*(k.* x(i) - w.*t(j))).*cos(50*(k.* x(i) - w.*t(j)));
end
pause (0.1)
plot(y)
%fill(x,c,'b')
axis([1,1000,-2,2])
grid
end
This code will generate a propagating AM wave.
