Problem with Modulator’s setting

[Subhash Arya]

Dear All,
I am trying to replace the exiting LiNbO3 (dual drive) based modulator with my own designed Modulator, but I am unable to get the expected constellation diagram (attached here). What may the the issue. I have taken 56 Gbps coherent 16 QAM back to back with DSP example given is sample for simulation.
Thanking you.

Attachments:

1. 

   Constillation-diagram-with-PN-56-Gbps.jpg
   

[Ahmad Atieh]

Hello Subhash,
Could email me your project as a zip file to ahmad.atieh@optiwave.com to debug it? It is difficult to debug the issue.
From the constellation graph, the modulation is not 16QAM. I see only 8-spots, which may indicate 8QAM placed circular.

Regards,
Ahmad

[Subhash Arya]

Dear Sir,
Thank you for respond. I have sent both files, i.e. original one as well as modified one on your email. Please look into the problem and suggest to overcome the problem.
With regards,
(Subhash Arya)

[Ahmad Atieh]

Hello Subhash,
Unfortunately, I didn’t receive the files. You need to send them as zip files.
Regards,
Ahmad

[Subhash Arya]

Dear Sir,
I have sent now file as zip file. Hope this time you shall receive.
With regards,
(Subhash Arya)

[Author]

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