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Waht is Background Electric Field?

Mohammad Parvinnezhad Hokmabadi

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Hi Guys,

I can not understand the meaning of background electric field.
In scattered field solution, one has to specify background electric field.
What does it mean?
What is the difference between Full Field and Scattered Field study?
I appreciate guys answering my question.

Thanks,
Mohammad

3 Replies Last Post 16 janv. 2016, 21:04 UTC−5

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Posted: 1 decade ago 21 août 2014, 10:46 UTC−4
Background fileld is just the external wave in scattered field formulation.
Background fileld is just the external wave in scattered field formulation.

Mohammad Parvinnezhad Hokmabadi

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Posted: 1 decade ago 21 août 2014, 11:17 UTC−4
Thank you Pu for your answer.
Yes, that is right.
When I put port boundary and define the source, I have feeling about that. That is the incident electric field. and model is solved in full field. It is kind of easy to understand.
But, I just can not understand scattered field solution.
I read through some discussions and I figured out when we have one homogeneous medium that surrounds the main structure under study, the background field should be the same as incident field.
But when we, have two materials surrounding the structure, like two semi-infinite spaces (Air-Si), what will be the background field.
It says in discussions that it is supposed to be superposition of incident, reflected and transmitted fields.
But I can not understand that.
For example in air side of this structure we have just incident and reflected field and in Si side we have just transmitted field. So, if I want to insert superposition of those fields, comsl may consider in every background material (Ait and Si) there are those three waves. While we know that in air side we have jus incident and reflected and in Si side we have just transmitted wave.
I appreciate if you answer this.
Then I have another question when we do two step study tu put background field from the dfirst step for the second one.
Thank you Pu for your answer. Yes, that is right. When I put port boundary and define the source, I have feeling about that. That is the incident electric field. and model is solved in full field. It is kind of easy to understand. But, I just can not understand scattered field solution. I read through some discussions and I figured out when we have one homogeneous medium that surrounds the main structure under study, the background field should be the same as incident field. But when we, have two materials surrounding the structure, like two semi-infinite spaces (Air-Si), what will be the background field. It says in discussions that it is supposed to be superposition of incident, reflected and transmitted fields. But I can not understand that. For example in air side of this structure we have just incident and reflected field and in Si side we have just transmitted field. So, if I want to insert superposition of those fields, comsl may consider in every background material (Ait and Si) there are those three waves. While we know that in air side we have jus incident and reflected and in Si side we have just transmitted wave. I appreciate if you answer this. Then I have another question when we do two step study tu put background field from the dfirst step for the second one.

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Posted: 9 years ago 16 janv. 2016, 21:04 UTC−5
Hey,

Have you figured out the problem. I am also curious about it.
Hey, Have you figured out the problem. I am also curious about it.

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