Documents about port definition in HFSS
I am very new to using Ansoft HFSS.
Can anybody suggest a good comprehensive documentation / tutorial on port definition. I found a few examples online, but the reasons behind chosing those steps is not clear there.
I am interested in understanding and of course using
1. Lumped port and Wave-port
2. Port size
3. Terminal lines
etc.
Any help will be greatly appreciated.
Thanks
Swagato
Hey,
I have a tutrial on how to make a port for the CPW. Is that what you want?
Let me know and if that is ur requirement, I'll send it to you.
Ananth.
Hey Schak,
Someone wanted the tutorial for the CPW. I have uploaded it. Youc an take a look at that.
Ananth.
Hello ananth, i'm Sirac and i'm a new italian member of this Forum.
I also ask you please to download the tutorial.
I have also a problem on modeling using HFSS.
Thanks
With sincere appreciation
G.S. :)
PS.My email is:siracg99@libero.it
the tutorial materials from ansoft, wish it would be helpful to you.
Best Regards,
I think Wave port and Lumped port are almost same.The only difference is that where they can be used..For example in case of dipole the port has to be interior so we use lumped port.
Terminal lines just give u the reference direction of the field or voltage..Aroow head is +ve and the tail is -ve.
Sonu
Hi all,
There is a comprehensive whitepaper in Ansoft's HFSS Online Technical Support site. Look for "How to model on-PCB structures with HFSS". In appendix D you will find everything you need to know about ports.
Itai
don't you have to have an account to access that site, because i tried to get one from ansoft and they bascially said to bad. told them i am a student and what school i go to and they still didn't care, even though my school has hfss
I'm confused about the question where I should use wave port and Lumped port.
I did some experiments this night to see the difference of a model with various ports.
Maybe I creat the ports faultily,I see some difference.
I believe there should be the same result with various ports.
Would you like to give me some advice in detail?
TKS
With lump port=> the excitation is applied at a point/cell, as a voltage or current.
With wave-port=> the excitation is so-called eigen-wave, such as the quasi-tem wave supported by a microstrip line. It applies over a cross-sectional area.
voltage is scalar, wave is vector by nature, hence there are substantial difference between the two. So use waveport whenever possible, because "simulation of wave phenomenon" is what HFSS is designed for. And compare with the "correct" measurement whenever possible (i.e. measure "wave", not simply "voltage").
Why lumped port is there? It is easy to applied and people found that good/reasonable results can be obtained. Why? if the frequency is low enough or the excitation is applied at sufficiently small area, then the "wave" can be described by some "voltage" or "current", which must be "measured"/"calculated"/de-embedded/etc in the correct manner.
if the excitation can be applied on some locally uniform region=>waveport,
if geometry/material discontinuities are near/closer to the point of excitation=>lumped port might be the only way.
The subject of lumped vs wave port is actually complicated. people continue to study related matters, (e.g. arguing what is the "characteristic impedance").
Reading about the various de-embedding scheme should help with the understanding....
I'm a freshman.
I believe we can get the same result with either wave port or lumped port where the condition is fit.
So I did some work to check whether I had gotten the skill well.But I can't get the same result with lumped port and wave port.
Would you like to check them for me?
Thank you!
regarding xbtxbt's projects (upstairs):
1. the background is perfect conductor by default, so right now the model is just a cavity filled with the RT/duroid. Obviously you want to simulate something on microstrip, so you need to draw a box or sphere surrounding all the objects in the existing project, assign it as air, and put radiation boundary on its surface.
2. for wave ports, your Rectangle1 and Rectangle2 should be assigned as perfect conductor, so that the wave is launched toward their outward normal, not both direcitons.
3. couldn't find your definition of lumped ports. the two projects uploaded look the same.
Hi all,
I am also quite new to EM simulations. I found the exhaustive reply from Loucy on Wave ports and Lumped ports. Also I found this in the HFSS online help.
"Lumped ports are similar to traditional wave ports, but can be located internally and have a complex user-defined impedance. Lumped ports compute S-parameters directly at the port. Use lumped ports for microstrip structures"
.Loucy says , for microstrip structures, one should use wave ports as it excites an eigen-mode ( quasi-TEM mode) that is actually found on a microstrip but HFSS help asks us to use a lumped port for the microstrip structure.
Can Loucy or any one clarify
-Arun
"Use lumped ports for microstrip structures" is different from:
"Use ONLY lumped ports for microstrip structures", or
"Use lumped ports ONLY for microstrip structures"
It seems you have read the sentence in the first inaccurate way. Please do not take the above discussion as exhaustive. The software manual is not exhaustive either.
hi
I'm grateful to you of your reply !~
I made a mistake when I saved the file.So I post the same ports.Very sorry!
I just hope to careat the two models and see the same result with the two different ports.But at first,I can't.Later,I find when I set the lumpped port,I make the boundary overlapped with the face on which lumpped port was set.
If I enlarge the area of air box to get rid of the error,I can get the same result with the wave port model
By the way,if I make my model uncovered with anything.In other words,if I don't draw a air box on the model,how the program will handle it?
It will take the boundary touched with the outer place as perfect E?
So even if the substrate surface is insulation material,the program will take it touched with perfect metal as default?
Thanks
best regards
hi, xbtxbt
Could you please upload your lumped port example again?
Many thanks!
saryee
You can refer to the Technology Note of the HFSS v8.05.
you will get help from the example from the full documents of hfss9.2
https://www.edaboard.com/ftopic124784.html
hope it helps
You can get help on HFSS ports in the HFSS help manual itself. This will be found under the help folder in the ansoft file installed in your program files folder on the local disk drive
hi,
I have a wire antenna and the end of this antenna has a terminator load which is 50 ohm. and this antenna is excited by waveguide.
I draw this antenna in hfss. But I dont know how to define a waveport and the terminator load in hfss.
can you make me define these in hfss?
i am waiting for your aids.
thanks for your helps....
https://www.edaboard.com/ftopic264247.html -->> this link has a lot of information my problem...