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EM wave transimitted in transmission line physically

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buyan

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Actually, I am always wondering how the EM wave is transmitted in the transmission line, eg. microstrip line, physcially. Is it due to the electron movements under the force from E-field and H-field? Hope someone can help to clarify.
 

A.Anand Srinivasan

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EM waves used in transmission lines are generally very high frequencied and travel along the surface of the waveguide or whatever be it... this is called skin effect and is due to electrons only....
 

mihirtronics

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well buyan,
You should know about the various dominant modes in transmission lines (TE/TM) + the type of transmission line (parallel wire/coaxial/etc). You will have a better insight!!
 

buyan

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Hi mihirtronics, I know there are different modes for different transimission lines. I know those theories and mathematics formulas too. However, I am still wondering why and how the EMwave propagate in the real world. For example, if we drop a stone into a lake, we can see the wave is propagating and water surface is different. Lookslike, there is a force to push the wave away. Similarly, if we apply a GHz signal into a microstrip line, any inside change will occur for the microstrip line?

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A.Anand Srinivasan said:
EM waves used in transmission lines are generally very high frequencied and travel along the surface of the waveguide or whatever be it... this is called skin effect and is due to electrons only....

Hi Srinivasan,
Yah, I'm talking about RF & microwave. Could you kindly explain in details about "travel along the surface of the waveguide"? how does it travel? There must be sth for it to use to travel, right? Please correct me if I am wrong.
 

A.Anand Srinivasan

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EM waves do not require a medium to travel.... but waves that we use generally have some effect on the surface of the conductor due to their high frequency...
 

buyan

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A.Anand Srinivasan said:
EM waves do not require a medium to travel.... but waves that we use generally have some effect on the surface of the conductor due to their high frequency...

Thanks for your reply. Some effect means? electrons move under the EM field? BTW, for a microstrip line, the majority of the energy propagated is in the substrate between the top metal strip and ground plan if I am not wrong. So the surface of the metal strip exposed to air shouldn't be much affected, right?
 

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surface waves can be seen in them.... Surface waves are guided by the boundary between two media. Surface waves propagate along this boundary. Surface waves can be observed at microstrip transmission lines, where the wave does not propagate along the microstrip conductor.....
 

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