How to plot Message Signal using MATLAB ?? (Quick Question Need Help)
2 vues (au cours des 30 derniers jours)
Afficher commentaires plus anciens
Hi,
I have an output for a FM transmitter in the form:
y(t) = cos ( 2*pi*t + 2*pi (integral from 0,t of m(tau) dtau ) )
I need to create a message signal of the following:
m_1(t) =
{
1 when cos(t) >= 0
-1 when cos(t) < 0
}
I need to create the message signal above in MATLAB and then find the corresponding FM signal.
However, I am unclear on how to graph the message signal.. Can you please show me how?
Thank you.
0 commentaires
Réponse acceptée
Richard Brown
le 23 Avr 2012
First, note that the integral of the message will be zero up to any multiple of 2*pi. The integral will then be a piecewise linear function that only requires evaluating on [0,2*pi). It's straightforward to do this by hand
pp = interp1([0, pi/2, 3*pi/2, 2*pi], [0, pi/2, -pi/2, 0], 'linear', 'pp');
int_m = @(t) ppval(pp, mod(t, 2*pi));
Then a plot of your FM signal will be
fplot(@(t) cos(2*pi*t) + 2*pi*(int_m(t)), [0 20])
Plus de réponses (2)
Richard Brown
le 23 Avr 2012
m_1 = @(t) 2*(cos(t) >= 0) - 1
t = linspace(0, 100);
stairs(t, m_1(t))
3 commentaires
Richard Brown
le 23 Avr 2012
No, don't do that, it will be horrible!! (not wrong, just horrible)
See new answer below
Voir également
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!