Menu

Discussion Forum

New Discussion
Filtrer

Note: This discussion is about an older version of the COMSOL Multiphysics® software. The information provided may be out of date.

Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.

2D coplanar waveguide Port Modeling

Posted 4 avr. 2013, 05:53 UTC−4 RF & Microwave Engineering, Geometry Version 4.2a 4 Replies

Diana Geiger
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Hello everyone,

I have a very simple 2 D model of the crossection of a coplanar waveguide (substrate in an air box, at the boundary between substrate and air I have lines for the metallization). I want to set the center conductor line as active port. However, I cannot select any of the metallization lines for the port. Can anyone advise me how to deal with the port issue?
4 Replies Last Post 22 avr. 2013, 06:46 UTC−4
Edgar J. Kaiser Certified Consultant
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 4 avr. 2013, 06:05 UTC−4

Diana,

port boundaries must bei PEC or impedance boundary conditions. That is what I stumbled across when I tried it the first time.

Cheers
Edgar

--
Edgar J. Kaiser
www.emphys.com
Diana, port boundaries must bei PEC or impedance boundary conditions. That is what I stumbled across when I tried it the first time. Cheers Edgar -- Edgar J. Kaiser http://www.emphys.com
Diana Geiger
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 16 avr. 2013, 12:20 UTC−4
Hello,

thank you for your reply. However, I am still confused since also the impedance boundary condition does not take my boundary choice. Maybe there is something altogether wrong with my model of the cross section, could someone take a look? I simply want to include a RF excitation (travelling into the plane of my model) to the center conductor and see the field distribution.
Hello, thank you for your reply. However, I am still confused since also the impedance boundary condition does not take my boundary choice. Maybe there is something altogether wrong with my model of the cross section, could someone take a look? I simply want to include a RF excitation (travelling into the plane of my model) to the center conductor and see the field distribution.

Attachments:

Edgar J. Kaiser Certified Consultant
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 16 avr. 2013, 12:56 UTC−4
Diana,

I indeed think that the model is not appropriate. My comments:

1. The metallization is modelled infinitely thin. This results in singularities

2. In planar symmetry you can't send a wave into the plane. If you connect a lumped port it would be connected all along the plane's normal direction. This is probably not what you want.

I put a lumped port into your model to show in principle how a lumped port is to be defined. The lumped port always connects two PEC or impedance boundaries. However for the above mentioned reasons this will still not do what you want.
I think you must go to 3D and model the conductor with finite dimensions, not just as boundaries.

Cheers
Edgar

--
Edgar J. Kaiser
www.emphys.com
Diana, I indeed think that the model is not appropriate. My comments: 1. The metallization is modelled infinitely thin. This results in singularities 2. In planar symmetry you can't send a wave into the plane. If you connect a lumped port it would be connected all along the plane's normal direction. This is probably not what you want. I put a lumped port into your model to show in principle how a lumped port is to be defined. The lumped port always connects two PEC or impedance boundaries. However for the above mentioned reasons this will still not do what you want. I think you must go to 3D and model the conductor with finite dimensions, not just as boundaries. Cheers Edgar -- Edgar J. Kaiser http://www.emphys.com

Attachments:

Purushottam Garg
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 22 avr. 2013, 06:46 UTC−4
how to design input and output coplanar waveguide so they can be coupled .
how to design input and output coplanar waveguide so they can be coupled .

Note that while COMSOL employees may participate in the discussion forum, COMSOL® software users who are on-subscription should submit their questions via the Support Center for a more comprehensive response from the Technical Support team.

Suggested Content