how to get the exact value of jitter

[Joseph Jiang]

hi,everyone,i want to measure the jitter of my system.i know we can see the jitter by EYE DIAGRM,HOWEVER,I WANT TO KNOW THE EXACT VALUE OF THE JITTER?IS THERE ANYONE KNOW IT?THANK YOU!

[Joseph Jiang]

can anybody help me？thank you in advance！

[Damian Marek]

I think the intrinsic randomness of jitter might make it tough to calculate the exact jitter of a signal. The easiest way I understand how to find jitter is as you said the eye diagram.

Here is an intro to measuring jitter in OptiSystem.

Signal degradation – Jitter

[Joseph Jiang]

OK，Thank you Damian.In my application(optical time transfer) ,i just want to measure the exact jitter of a signal.in many papers,they get the jitter using SNR with a function.however ,how can we achieve the SNR in a digital communication system.Damian,i really need your help!thank you!

[Damian Marek]

Yea I think I read about that sort of empirical method for finding jitter. You can calculate the OSNR/SNR from the WDM Analyzer/Carrier Analyzer for both Optical and Electrical signals. Or you could do it from the spectrums and calculate it by hand.

Regards

[Joseph Jiang]

thank you!Damian!i just want to know how the optisystem calculate the electrical SNR when the signal is digital.as we know,in digital communication systems,we often use BER to calculate the performance rather than SNR.SO HOW THE optisystem calculate the SNR?thank you
!

[Damian Marek]

OptiSystem would only measure the BER of a digital signal. I am not sure how it is possible to calculate the SNR from a digital signal, except perhaps having some sort of plot of BER vs SNR as a reference.

OptiSystem will calculate the SNR by directly comparing the spectral power distribution at the signal wavelength to the power distribution far away from the signal wavelength and thus representing noise.

[Joseph Jiang]

hi damian,as we know ,if i moudulate the digital signal to the laser and demodulate with a PD,it is a digital communication system.i want to calculate the electrical SNR after receiving from PD.i know there is a device’Electrical Carrier Analyzer (ECAN)’which can calculate the electrical SNR.SO,can it calculate the SNR i want?or is it just calculate the SNR of anolog singal！thank you!

[Joseph Jiang]

HI，damian，I am waitting for your reply？thank you！

[Damian Marek]

Yes you can. The Electrical Carrier analyzer will directly compare the signal power to the noise bins power. Note: For the case of electrical SNR you need noise bins to run the calculation and so the global parameter “Convert Noise Bins” should not be checked.

Sorry for the later reply the office was closed for the holidays.

Regards

[mohammed mostafa]

may be useful
https://www.sigcon.com/Pubs/news/3_22.htm

[shivakumar rjgr]

hello everyone,
i HAVE BEEN WORKING ON WDM SYSTEMS.I WANT TO MEASURE THE TIMING JITTER OF THE SYSTEM. PLEASE EXPLAIN TO MEASURE THE JITTER VALUE FROM EYE DIAGRAM. IN RESULTS OF BER ANALYSER, THERE IS A VALUE NAMED ” RMS JITTER AT USER DEFINED THRESHOLD”, COULD IT BE THE JITTER VALUE OF THE SYSTEM.PLEASE HELP

[Author]

Posts