Reflection and transmission of signal

AI Thread Summary
To determine the percentage of a signal reflected and transmitted through a wall, key parameters include the wall's permittivity, permeability, and conductivity. These properties allow for the calculation of the wall's complex impedance, which is essential for deriving reflection and transmission coefficients. Additionally, some signal energy will be absorbed by the wall, complicating the overall assessment. A practical approach is to use a field strength meter to measure the signal's strength on either side of the wall. Understanding these factors is crucial for accurate signal attenuation analysis in various wall constructions.
anarachy
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How do I determine what percentage of a signal is reflected and what percentage goes through a wall.
I know that I am over simplifying things, but for the purpose of my project I need a simple answer to this problem.
What parameters are needed for the solution and how do we calculate this.

Thanks.
 
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What signal are you referring to, the electromagnetic waves? If so, then you need to know some properties of the wall such as permittivity, permeability, and conductivity. You can use that information to calculate the complex impedance of the wall. Then use the complex impedance to calculate the reflection and transmission coefficients.
 
Besides some of the signal passing through the wall and some of the signal reflecting from the wall, some of the signal will also be absorbed by the wall. I can understand the importance of wanting to know how much the wall attenuates the signal but I do not understand why you want to know how much signal is reflected by the wall.

The easiest thing to would be to get a field strength meter and measure how much weaker the signal is on the other side of the wall compared to the same distance without a wall. Walls vary greatly in their construction and it is impossible to generalize about the characteristics of anyone wall. Loss factors in RF are usually expressed in dB instead of percent.
 
waht said:
What signal are you referring to, the electromagnetic waves? If so, then you need to know some properties of the wall such as permittivity, permeability, and conductivity. You can use that information to calculate the complex impedance of the wall. Then use the complex impedance to calculate the reflection and transmission coefficients.

Could you may be explain a little further with an example. Or refer a paper which has a table for reflection and transmission coefficients.

Thanks
 

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