Waveguide losses

Please login with a confirmed email address before reporting spam

Hi, I am simulating a 90° strict curve of a WR42 waveguide where TE10 mode is sent as input. As it can be seen from the image attached, the TE10 mode is almost completely lost and no field seems to be transmitted, this is confirmed by the fact that if I integrate the power flow over the output port only a very small fraction of the input power is left. If I check the Ohmic losses ( integrated over the lossy copper surface ) they are close to zero, and also mode conversion to higher order modes is not present (transmission coefficient of the S-matrix close to zero). What loss mecanism could be the cause of this loss of energy?



1 Reply Last Post 18.12.2023, 18:27 GMT-5
Robert Koslover Certified Consultant

Please login with a confirmed email address before reporting spam

Posted: 4 months ago 18.12.2023, 18:27 GMT-5
Updated: 4 months ago 18.12.2023, 18:47 GMT-5

Sudden bends in waveguide lead to reflections. Your sudden 90 deg bend presents a very serious mismatch. Suggestion: Chamfer the outer corner of your bend (by perhaps half the guide width; be sure to experiment with different values to find the best amount) and then try it again. You should see a huge change.

Examples of how it looks (see figure 2): https://www.radartutorial.eu/03.linetheory/tl15.en.html

-------------------
Scientific Applications & Research Associates (SARA) Inc.
www.comsol.com/partners-consultants/certified-consultants/sara
Sudden bends in waveguide lead to reflections. Your sudden 90 deg bend presents a very serious mismatch. Suggestion: Chamfer the outer corner of your bend (by perhaps half the guide width; be sure to experiment with different values to find the best amount) and then try it again. You should see a huge change. Examples of how it looks (see figure 2): https://www.radartutorial.eu/03.linetheory/tl15.en.html

Reply

Please read the discussion forum rules before posting.

Please log in to post a reply.

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.