urgent help how to plot eye diagram

[syed_brunel]

eye diagram

i would like to know that how to plot my signal in the form of eye diagram , if i dnt want to use any toolbox, i have found command on matlab
% Create an eye diagram scope object
h = commscope.eyediagram;
% Prepare a noisy sinusoid as input
x = awgn(0.5*sin(2*pi*(0:1/100:10))+ ...
j*0.5*cos(2*pi*(0:1/100:10)), 20);
% Update the eye diagram
update(h, x);
% Display the eye diagram figure
plot(h)

but if u see that the plotting is only for the h , if i have a signal how can i show it in the form of eye diagram.

your early response will be highly appreciated.

Syed@edaboard

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[Mad I.D.]

diagram of the eye

Just plot all the simbols on the same plot (hold on) in pairs. That is, you plot first two simbols, then on top of them next two etc.

 

[syed_brunel]

how to plot eye diagram in matlab

i didnt get u mate .. will you clearify this

 

[Mad I.D.]

eye diagram

i didnt get u mate .. will you clearify this

Of course.
Well you basically transfer symbols (each carrying N number of bits) through you're comm. channel, OK ?

So, what you wanna see is how symbols overlap when you draw a bunch of them on top of each other, right?

So, you plot first two symbols on a graph. You make sure that plot "hold on" is active and then you plot next 2 symbols on the same plot and so on. Whola, this is you're eye diagram.

The eye diagram is constructed by overlaying plots of the waveform from successive unit time intervals.