MY VIVALDI SIMULATION
I HAVE DESIGNED ANOTHER VIVALDI ANTENNA BETTER THAN THE ONE THAT I POST YEASTERDAY AND YOU CAN FIND IT ATTACHED.
IT IS JUST A TRY AND IT ISN'T THE OPTIMOUS SOLUTION.
I HAVE SIMULATE IT WITH MW STUDIO 5 AND EVERYTIME THAT LANCH THE SIMULATION THERE IS PROBLEM ABOUT THE PML BOUNDARY AND ABOUT PORT.
I HAVE CHOOSE OPEN BOUNDARY EVERYWHERE (NO IN YMIN) AND I HAVE DEFINE A PORT WITH DIMENSION XMIN-XMAX.
I DON'T KNOW HOW TO SOLVE MY PROBLEM.. WHERE I WRONG?
THANKS AND REGARDS,
ALESSANDRA
Pack whole project directory with deleted results before and post.
.sat tell nothing about PML boundary
eirp
Hi,
Before you go and make your own design I would suggest that you first try and duplicate the results of the "2000 CAD benchmark" vivaldi antenna (all geometry info is online). I did it in HFSS v9.1 without too many problems. The biggest issue I had was making sure that the mesh was accurate enough. Make sure that you plot the mesh and check otherwise you might get weird results.
gregb3d
to eirp:Hi! I think that you haven't need of my result.. tomorrow i'll post another file .sat with results!
to greg b3d: thanks for good suggestion! I'll try to follow this way!
bye alessandra
Hello, Alessandra
There's a major mistake in your project :)
Material defined as copper have conductivity=0! Change to PEC for simplicity.
Also a detail, material FR4 have the same properties as air (eprs=0).
I will post a modified project with extra stripline feeder soon
cheers
eirp
Here's improved model. I've modyfied also mesh settings slightly.
Cheers
eirp
TO EIRP:
HI! I DON'T UNDERSTAND WHY YOU DON'T SEE THE CORRECTS PROPERTIES OF ANTENNA'S MATERIAL. I HEVE LOOKED MY PROJECT AND I SEE THE COPPER WITH THE CORRECT CONDUCTIVITY AND FR4 WITH THE CORRECT DIELECTRIC ROPERTIES. IT IS SO STRANGE... MAYBE IT DEPENDS ON .SAT FILE. IN FACT WHEN I DOWNLOADED THE VIVALDI WITH EXPONENTIAL TAPER BY THIS FORMUN I DIDN'T SEE CORRECTLY THE PROPERTIES WITH CST.
I DON'T KNOW WHY...
THEREFORE I WANT TO THANK YOU FOR YOUR SUGGESTION ABOUT ALIMENTATION PORT OF MY ANTENNA. I TRY TO SIMULATE MY DESIGN WITH JUST OPEN BOUNDARY AND A THICK OF AIR BETEEWN ANTENNA AND PML. IN THIS WAY THE SIMULATION RESULTS MORE SPEED ON MY PC. YOUR DESIGNE WITH "OPEN ADD SPACE" BOUNDARY TAKES MORE TIME.
TOMORROW I'LL BE IN SICILY FOR MY HOLIDAY...
WRITE U SOON. THANK YOU.
ALESSANDRA
Hello!
sorry me, of course .sat don't contain material properties :) It's only geometry file..
I suppose with open boundary only the results will not be fully correct, especially for radiation pattern.
You should use "open add space" for all antenna calculations to cover the near field..
Check the results for "open" and compare...
Greetz
eirp