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measuring absorption of material using S parameter

Posted Mar 26, 2012, 11:33 a.m. EDT Version 4.2 3 Replies

Devika Kataria Electronics Engineering
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I am trying to measure absorption of a material in a rectangular block by using formula 1-S21^2. For simulation , i have used a rectangular geometry at top of which i have Port 1 and at bottom edge Port2 .The material inside the rectangle has n=1 and k=0.5 whereas outside the rectangle is air with n=1 and k=0. I tried to verify the result using Beer's formula ie., 1-exp(-4*pi*k*d/lamda).There is discrepancy of 10%. I need to understand ,why is there discrepancy in the simulation using S parameter and the calculation using Beer's law.
3 Replies Last Post Mar 2, 2015, 7:37 a.m. EST
Alexander Kuznetsov
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Posted: 1 decade ago Mar 26, 2012, 12:46 p.m. EDT
S11^2 is reflection, S21^2 is transmission. Absorption is 1-S11^2-S21^2.
S11^2 is reflection, S21^2 is transmission. Absorption is 1-S11^2-S21^2.
Devika Kataria Electronics Engineering
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Posted: 1 decade ago Mar 31, 2012, 1:36 p.m. EDT
Thanxs Mr Alexander. I would also like to know why my answer using this formula does not match with Beer's law which says absorption=1-exp(-4*pi*k*d/lambda), k being extinction coefficient and d being distance travelled by light in medium with extinction coeff k.
Thanxs Mr Alexander. I would also like to know why my answer using this formula does not match with Beer's law which says absorption=1-exp(-4*pi*k*d/lambda), k being extinction coefficient and d being distance travelled by light in medium with extinction coeff k.
Min Song
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Posted: 10 years ago Mar 2, 2015, 7:37 a.m. EST
Hello Alexander,
Do you know how to use S-parameter to get the absorption in each layer for a 5-layers structure? I set a port in each interface between layers. Only port 1 is on with 1W incident power. What can we get from the interface ports?
Hello Alexander, Do you know how to use S-parameter to get the absorption in each layer for a 5-layers structure? I set a port in each interface between layers. Only port 1 is on with 1W incident power. What can we get from the interface ports?

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