How to analyze resistor of an RF coil?

[Jim]

I have an RF coil. Some material having strong absorption for 100MHz RF is placed
inside the coil. X", size and position of the absortive meterial is known.
How can I simulate the resistor of the RF coil at the specific frequency of 100MHz?
Thank you very much!

 

[Don Pearce]

On 21 Nov 2004 15:22:00 -0800, jmgong74@tom.com (Jim) wrote:

I have an RF coil. Some material having strong absorption for 100MHz RF is placed
inside the coil. X", size and position of the absortive meterial is known.
How can I simulate the resistor of the RF coil at the specific frequency of 100MHz?
Thank you very much!

Put a variable capacitor in series with the coil and resonate it with
the inductor at 100MHz. What remains is now only the equivalent
resistance to the lossy material. Measure this by placing the whole
thing in parallel with a 100MHz signal and seeing how much it is
reduced. Substitute fixed resistors to find the equivalent value.

d

Pearce Consulting
http://www.pearce.uk.com

 

[Jim]

Thank you both very much!
My object is to optimize the coil structure to get maximum resistor
change.

I hope I can use some simulation method like FEM, FDTD etc. to analyze
the relation of the resistor and coil structure.

Thanks again!