# CPW feeding simulation with HFSS problem , (SMA vs port) (lupmed port vs wave port)

1. ## CPW feeding simulation with HFSS problem , (SMA vs port) (lupmed port vs wave port)

Hi All,
I'm working on ungrounded CPW structure. I've been through all previous post about CPW , how to feed it and Ansoft tutorials,and I designed a cpw antenna with SMA. From Antenna_kit released by ansoft I realized that the length of the coax should be Lambda/6. So I simulated my CPW with 4 different feeding, 1.SMA with Lambda/6 length, 2. SMA with short length, 3. Wave port as recommended by some tutorials (width=3(2*s+w) and height=4*h) and finally 4. lumped port as I've seen in some examples.
But the problem is I've got 4 DIFFERENT results by 4 different feeding. For better understanding I attached the HFSS file.
I wonder if anybody could help me and tell me which result is correct?

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2. ## Re: CPW feeding simulation with HFSS problem , (SMA vs port) (lupmed port vs wave por

hi
i send a model of CPW antenna this method will work and the best and i checked it with some paper result and also i check the result with CST and achieve same result

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3. ## Re: CPW feeding simulation with HFSS problem , (SMA vs port) (lupmed port vs wave por

Thanks a lot.

2 members found this post helpful.

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4. ## Re: CPW feeding simulation with HFSS problem , (SMA vs port) (lupmed port vs wave por

Hi
i have the same problem about CPW antenna ,so i load the model you sent , but i have some questions ,i saw you built three rectangle (rectangle 4,5,7) around the lump port and unite them ,but how do you determine the size of the rectangle , whether their width and height influence will influence the result

5. ## Re: CPW feeding simulation with HFSS problem , (SMA vs port) (lupmed port vs wave por

I have the same question.

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6. ## Re: CPW feeding simulation with HFSS problem , (SMA vs port) (lupmed port vs wave por

about your questions when u model a antenna structure in hfss or other simulators u it should be same as real condition to give the best result
in here i used the HFSS techniques but for the size u can check how the SMA will connect to your antenna so u can realize the size of this u shape too easy i hope it helpful for u

7. ## Re: CPW feeding simulation with HFSS problem , (SMA vs port) (lupmed port vs wave por

Originally Posted by ferdows
about your questions when u model a antenna structure in hfss or other simulators u it should be same as real condition to give the best result
in here i used the HFSS techniques but for the size u can check how the SMA will connect to your antenna so u can realize the size of this u shape too easy i hope it helpful for u
Thanks, I am trying to implement a CPW line which will be fed with a probe of some kind or SMA. But it is not obvious to me how the structure in the file simulates an SMA connector. I was hoping you could elaborate?

Thanks a lot!

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