[boldooParticipant]

my schema is attached. Eye diagram is seems like very big. is there any way to correct it?

Attachments:

1. star-16QAM.osd

[boldooParticipant]

yeah, me too. I don’t really understand principle about BER in optisystem. if you got answer, pls share me. Thx

[boldooParticipant]

is there must be DSP when I want to get BER and eye-diagram?

for star-16QAM, there is no DSP in Optisystem. how can I get almost real values for BER?

[boldooParticipant]

Amplifier 2 db is too low. it should more than 10dB, right? what does it mean Power parameter of Receiver?

[boldooParticipant]

first amplifier is 0db. second amplifier is 2dB through 16km fiber. you mean it is too low?

how to set sensitivity limits?

[boldooParticipant]

Hi Damian,

please check attached project. i created 16APSK signal after modulator. But After fiber and amplifier, constellation is very bad. is there any way to keep constellation as possible? what components was wrong ?

Attachments:

1. 16APSK.osd

[boldooParticipant]

thanks Damian,

now that 16QAM pass through fibers, constellation is rotated as certain phase. but i can’t fix this to correct phase. You can see another post of mine.

[boldooParticipant]

thanks sir

[boldooParticipant]

thank you dears but it can’t change phase shift. I posted another forum, please review it.

thanks

[boldooParticipant]

Yes, I exactly need Dispersion compensating fiber. DCF. In optisystem, i didn’t find it.

if you know it, please share me

[boldooParticipant]

when I deselect “group velocity dispersion” and “third-order dispersion”, constellation map showed almost clear. just attenuated.

do you have idea about to correct the dispersion? need other components?

[boldooParticipant]

I’m using revision 13. do you remember which parameters set? and how about components ? amplifier, filter.. is that enough?

[boldooParticipant]

yes, reference wavelength is 1550nm at TX, RX and fiber and filters. same

[boldooParticipant]

I’m trying to apply 16QAM.

after transmitter, connected to amplifier and Gaussian filter then 50km fiber, then amplifier and filter.

After second filter, I checked 16QAM coherent Receiver and Constellation Visulaizer.

but result is like attached.

[boldooParticipant]

Dears, since I need to draw 16QAM constellation, I asked about 2ASK. then I drew attached fig.

is it 16QAM right? there is any requirement?

Attachments:

1. 

   attach.jpg