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## S-Parameters in physics Magnetic Fields

Hello! I would know if it's possible plot S-parameters in the model about Magnetic Fields or it's exclusive about model Radio Frequency?

4 Replies Last Post Sep 6, 2023, 5:19 p.m. EDT

Posted: 11 months ago

Hi Igor,

S-parameters are power ratios of some kind of ports with some kind of transmission in between. How would that look like in mf in your case?

Cheers Edgar

-------------------
Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com

Posted: 11 months ago
Updated: 11 months ago

Hello Edgar! This question is because I need to simulate a system about wirelles power transfer using ressonant coils and it's will be operate in frequency around 1 MHz. Therefore, to correct avaliate about the eficiency of system, the S-parameters is going to more useful. Furthermore, with the S-parameters I can verificate if the minimum value S11 will be occur in the ressonance frequency.

Posted: 11 months ago
Updated: 11 months ago

In a transmission line system the S parameters are defined as ratios between incoming and outgoing waves. Those waves can be expressed in terms of the terminal voltages and currents. So if you have a calculation that yields terminal voltages and currents (for example, mf or es physics) you can calculate S parameters (which will be dependent on the transmission line impedance assumed). It is easy enough to calculate the S parameters in post-processing although they are not a predefined quantity in mf physics.

You can find the definitions for the waves and the S parameters in the usual textbooks or on the web.

(It is interesting that the waves are referred to as power waves despite the fact that they have the dimensions of voltage in many definitions).