what is the eye pattern in digital communication ?

Dear Sir,
I wanted to know what is the eye pattern in digital communication and how it is useful for our receiver quality measurements.
Thanks
Pardeep

eye pattern oscilloscope

in digital communications, we have either a pulse of one or a pulse of zero.
if you superimpose these two pulses on each other for several times, you will get a pattern like an eye (take into consideration that a pluse is not a sharp rect and has a rise and fall time).
if you have noise on your pulses, it is called that the sye closes.
this noise can either change the pulse amplitude which results in the closure of the eye as you push the upper sides of the sye.
if you have a noise that changes the timing of the pulses, you will have a jitter that will close your eye form left and right side.
i will attach a photo describing this concept later.
I do not have it now with me.

eye diagram digital communication

In short, eye diagrams are used to check for ISI i.e intersymbol interference in a digital communication system. ISI can be removed by a process that is referred to as equalization.

how to generate eye patern?

hi!
this is a photo on eye diagram.
rgs

plot eye pattern

Eye diagram is the data transtion of the digital signal for testing whether the device is pass the protocal or not.
It is for testing the falling time/rising time/hold time.... of the device.

eye pattern in digital communication

Yeh eye diagram tell you that how much ISI will be present at the receiver side....You just have to see in your eye diagram that at ur sampling point how much is the eye opening.If the eye opening is wider then means less or no ISI or otherwise...

eye diagram+digital communication

Who you can generate it with HSPICE?

isi eye pattern

An oscilloscope display in which a pseudorandom digital data signal from a receiver is repetitively sampled and applied to the vertical input, while the data rate is used to trigger the horizontal sweep.
Note: System performance information can be derived by analyzing the display. An open eye pattern corresponds to minimal signal distortion. Distortion of the signal waveform due to intersymbol interference and noise appears as closure of the eye pattern.

how to plot eye pattern of a modulation scheme

can any body tell how to calcultae the eye mask values.

eye pattern matlab

Hi,

i have noticed one thing while ploting eye pattern in matlab that eye pattern varies for same modulation scheme and same sample to symbol ratio.
how is it so when same specs are used for particular modulation scheme.

regards

eye pattern diagram

Horizontal opening of the eye signifies the timing jitters
and vertical opening of the eye determines the diffrence between the logic High and logic low in case of the Digital Communication System.

how to create eye pattern

hi pardeep

you can use hspice to generate

* Eye Diagrams
* This type of diagram is to reduce a large amount of data to
* one frame. Data from a fixed period is superimposed upon
* itself.
*
* An e source is setup to create a sawtooth.
* The sawtooth period is the window to be plotted, eyewidth. i.e. if
* you are looking at a periodic signal and want to know if the
* period or amplitude drifts over a large time, then the
* eyewidth is set to the period of the data to be plotted and
* superimposed.
*
* In this example, Y is a damped sin wave at 1 Mhz. X is a 5 Mhz
* sin wave. The eyewidth is set to 2 Mhz. (Look at the difference
* between 2Mhz and 1Mhz as an experiment).
*
* To view output in Meta-Waves, place signal T on the x axis and plot either
* X or Y on the y axis. For the damped sin wave, notice that the
* frequency is constant but that the amplitude obviously decays.
* This is a view of all periods super-imposed on each other.
*
* Plot X, Y vs Time,
* X, or Y vs T
*
* Only 4 lines are needed to add eye diagrams to a circuit:
* Here they are:
* .Param EyeWidth = 2.0x $ Bandwidth
* eT T 0 Vol='(TIME*EyeWidth)-int((TIME*EyeWidth))'
* rT T 0 1k
* .Option Post

.Param EyeWidth = 1.0x $ Bandwidth

* a clever alternative here is to set .Param Eyewidth = '1/<clock_period>'

vX X 0 Sin ( 0v 3v 1xHz )
vY Y 0 Sin ( 0v 1v 1xHz 0s 500k )

* Simple time manipulation to create a sawtooth pattern
eT T 0 Vol='(TIME*EyeWidth)-int((TIME*EyeWidth))'

rX X 0 1k
rY Y 0 1k
rT T 0 1k



.Tran 10ns 10us
.Option Post=2
.End
*******************************************************

Re: how to create eye pattern

How do you measure the init point