Learning Forum

[maryam.rahmani]

Hi All,

I am simulating a simple superconductive coplanar waveguide on silicon substrate in HFSS. 

I'm trying to calculate the characteristic impedance of the line but no success! I have tried below measures but nothing has worked so far!!! I have calculated it analythically and want to compare my simulation results with the analythical calculations.

1-Since, I am simulating a finite thickness line, I have defined the superconductive's bulk conductivity using two-floid model complex impedance as a function of temperature and frequency.

2- Since the waveport does not accept a complex impedance, therefore I have added a PEC line in contact with the port and then connected it to the superconductive line and then deembeded the port to the location of connection of PEC-superconductor. This returns the PEC's characteristic impedance! I then set the post processing impedance to be normalized to the complex value of the superconductor's impedance but did not work again!!!!

3- I have tried the ports only setup but did not work!!!

4- I have used the lumped ports and set the impedance as the superconductor's complex impedance in the original port impedance and the post processing renormalization. Neither worked!!!!

5- I am using the field calculator, but since field calculator calculates the characteristic impedance in a single frequency, it does not work!!! I have used python scripting in HFSS again didn't work!!!!! Even that single point that the field calculator obtained is not correct!!!!!!!!!!!!!

I appreciate ANY KIND OF HELPS!

Thanks!

[Rong Liu]

Hi Maryam, 

 

You can refer to the example in File-->Open examples..-->HFSS-->Transmission lines--> Coplanar_waveguide.aedt or coplanar_wg_w_ground.aedt.

Note there is a white paper attached with the project, which is a pdf file and can be found in the project manager.

 

Best regards,

Rong