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.
RF Module, Direction of the global incident field
Posted May 20, 2010, 3:13 p.m. EDT 2 Replies
Please login with a confirmed email address before reporting spam
Hello,
I'm trying to modelise the scattered field in 2D around a round metal cylinder (wich is a circle in the 2D model). The idea is to see the scattered field around the metal cylinder produced by a 600 MHz incident wave. The metal circle is inside a rectangular wich is Air, and the whole thing is surrounded by a PML. The problem is that the result obtained is reversed from what I expected. The scattered field look like the incident wave is travelling from right toward left, but as I understand it, by default the incident wave is going from left to right.
How can I verify the direction of the incident wave?
Also, either in Scattered mode or Non-scattered mode, how can I turn off the global wave excitation if I want to use an excitation on a boundary for example?
I read the RF User's guide and RF Model Library, and the explanation of how to set up the excitation is not very detailed. So if anyone can help, it would be very appreciated.
Thanks,
Jonathan
I'm trying to modelise the scattered field in 2D around a round metal cylinder (wich is a circle in the 2D model). The idea is to see the scattered field around the metal cylinder produced by a 600 MHz incident wave. The metal circle is inside a rectangular wich is Air, and the whole thing is surrounded by a PML. The problem is that the result obtained is reversed from what I expected. The scattered field look like the incident wave is travelling from right toward left, but as I understand it, by default the incident wave is going from left to right.
How can I verify the direction of the incident wave?
Also, either in Scattered mode or Non-scattered mode, how can I turn off the global wave excitation if I want to use an excitation on a boundary for example?
I read the RF User's guide and RF Model Library, and the explanation of how to set up the excitation is not very detailed. So if anyone can help, it would be very appreciated.
Thanks,
Jonathan
2 Replies Last Post May 21, 2010, 4:58 p.m. EDT
Please login with a confirmed email address before reporting spam
Posted:
1 decade ago
I regularly use harmonic propagation module so I can comment on the way I have understood it. In that module, you "may" specify an incident field but that remains inconsequential until you also choose the option of "Incident field" on one of the (exterior) boundaries. Unless that is done, your specification of incident field in the scalar variables section of the physics menu remains ineffective.
As for exciting wave, again the way I have understood it, the first thing to note is that it should be done on the exterior boundaries of your geometry. So the boundary exciting the wave cannot have a PML to absorb back reflections. What you could do is to excite wave through scattering/matched/port boundaries and then hope that they manage to absorb back reflections to a good approximation.
One only way that I know of exciting wave from an interior boundary is to select the option of Magnetic field (or may be electric field too depending upon availability). But that is usually limited in applicability. It actually fixes down the value of magnetic field on the boundary which means that in case there is a back scattering from your object, this boundary will repel it back to the object because the possible magnetic field value has been specified fixed.
Hope that helps. And please let me know if you discover a method of exciting wave from interior boundaries without facing any of the issues I mentioned :)
Sometimes I so much wish there were a method of exciting wave after a PML layer because of obvious reasons.
As for exciting wave, again the way I have understood it, the first thing to note is that it should be done on the exterior boundaries of your geometry. So the boundary exciting the wave cannot have a PML to absorb back reflections. What you could do is to excite wave through scattering/matched/port boundaries and then hope that they manage to absorb back reflections to a good approximation.
One only way that I know of exciting wave from an interior boundary is to select the option of Magnetic field (or may be electric field too depending upon availability). But that is usually limited in applicability. It actually fixes down the value of magnetic field on the boundary which means that in case there is a back scattering from your object, this boundary will repel it back to the object because the possible magnetic field value has been specified fixed.
Hope that helps. And please let me know if you discover a method of exciting wave from interior boundaries without facing any of the issues I mentioned :)
Sometimes I so much wish there were a method of exciting wave after a PML layer because of obvious reasons.
Please login with a confirmed email address before reporting spam
Posted:
1 decade ago
Thank you very much for your help. It will help me a lot in trying to figure out how it works. I will play with it and try some modifications according to your suggestions. If I find something that could be interesting, I'll let you know.
Thanks again,
Thanks again,