Learning Forum

[Kang Donggil]

I would like to evaluate the performance of the MZI-based EO modulator by utilizing Lumerical's interconnect. (The parameter of TW electrode was extracted through HFSS of ANSYS.)

However, in the example provided, there were many explanations for the EYE diagram, but no explanations were found for how to obtain the EO bandwidth.

However, I found a similar file utilizing impulse response in the example of ring modulator, but it didn't work well in my case. (I had a problem where the bandwidth changes every time I change the sample rate)

So I'd like to know how to get EO bandwidth from EO modulator in general.

[Zhenwei Mo]

I also concern about this question. I want to use ENA to obtain the gain and group delay of an circuit composed of a EO modulator and optical dispersion components, but a warning of 'ENA_1: Warning calculating s-parameters: maximum number of iterations reached.' was shown while using scattering data for frequency domain simulation, and the input port of the ENA is empty.  I don't kown if time domain simulation shold be done, and have no idea on how to set the time domain simulation to get the right result.

[Devika Padmakumar Nair]

 

Hello Kang Donggil, Thanks for raising the question. I will get back to you with a solution. 

Meanwhile can you confirm this is the example you are talking about? Traveling Wave Mach-Zehnder Modulator – Ansys Optics

Hello Zhenwei, Please post as a seperate post in forum with more information and screenshots. It will be easy to followup and answer your question. 

Regards

Devika

 

[Kang Donggil]

I'm sorry for the late reply. As you said, the example I referred to is "Traveling Wave Mach-Zehnder Modulator – Ansys Optics".  Additionally, we tried the method of impulse response by referring to the example of "Ring modulator time domain (INTERCONNECT) – Ansys Optics", but we didn't get the desired result. In the example of ring modulator time domain, the result was consistent even if we changed sample rate(In the example script, it is represented by f span), but in my case, when we changed sample rate, we could see that EO bandwidth kept changing.

[YounusMandalawi]

Do we have any soluation yet? I have the same problem. When I try to replicate the results of the ENA by modulating a single tone and see the output power, it does not match. 

[Devika Padmakumar Nair]

Hello, Aplologies for the delay in response.

If the sample rate is high enough, the bandwidth shouldn't change much when increasing the sample rate.

So the reason for your simulation have noticeble change is because of small sample rate. Sometimes a high sample rate is required to get a good digital filter fit. 

You can try increasing the sample rate further to see how much the results changes.

Let me know if the issue is solved or further assistance required. 

Thanks and regards

Devika