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Hello, Ivar Kjelberg, help please
Posted 23 oct. 2014, 09:24 UTC−4 Version 4.4 2 Replies
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Dear Ivar
I have attached my model so you can see it. My probe is coaxial cable excited from one port with microwave signal. the other end of the coaxial cable will go up to two layers (samples) the first sample will be air and the second sample will be a material with relative permittivity equals to 2.
First, I will fix the end port in the sample 1(AIR) and the frequency equals to 0.1 GHz and calculate the reflection coefficient (S11) at the aperture of the coaxial
Second, I will repeat the first step with frequency equals to 0.3,1 and 3 GHz and calculate the S11 at each frequency.
When I did this the S11 increases with as the frequency increases and this result is wrong because as the frequency increases the S11 should decreases. There is some thing wrong, but I could not discover it.
If this works, I will fix the frequency and make the sweep parametric to move the probe up with step of 0.01mm from the sample1 to sample 2.
I think the problem in the boundary condition.
Please solve this problem for me.
Mabrouka
I have attached my model so you can see it. My probe is coaxial cable excited from one port with microwave signal. the other end of the coaxial cable will go up to two layers (samples) the first sample will be air and the second sample will be a material with relative permittivity equals to 2.
First, I will fix the end port in the sample 1(AIR) and the frequency equals to 0.1 GHz and calculate the reflection coefficient (S11) at the aperture of the coaxial
Second, I will repeat the first step with frequency equals to 0.3,1 and 3 GHz and calculate the S11 at each frequency.
When I did this the S11 increases with as the frequency increases and this result is wrong because as the frequency increases the S11 should decreases. There is some thing wrong, but I could not discover it.
If this works, I will fix the frequency and make the sweep parametric to move the probe up with step of 0.01mm from the sample1 to sample 2.
I think the problem in the boundary condition.
Please solve this problem for me.
Mabrouka
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2 Replies Last Post 27 oct. 2014, 06:53 UTC−4
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Posted:
1 decade ago
Hi
I believe the issue is that you have no surrounding air to allow the EM field to loop around. Do not forget that magnetic and EM fields are generated by current loops and field loops and here you allow neither to develop. The EM field enter into vacuum or air = the spatial region around your device and closes it's loop there, so you need to define our model completely otherwise it will not be physical and you are missing BC
Check the EM models and do a couple of those, then you will understand
--
Good luck
Ivar
I believe the issue is that you have no surrounding air to allow the EM field to loop around. Do not forget that magnetic and EM fields are generated by current loops and field loops and here you allow neither to develop. The EM field enter into vacuum or air = the spatial region around your device and closes it's loop there, so you need to define our model completely otherwise it will not be physical and you are missing BC
Check the EM models and do a couple of those, then you will understand
--
Good luck
Ivar
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Posted:
1 decade ago
Dear Ivar
Thank you for replying, Actually, I don't understand well what I need to do with my model. Could you explain with more details please.
Do You mean I have to surround all the outer cylinder by another one which is Air?
Thanks