Help me with calculating mutual capacitance

mutual capacitance

I want to get the derivation of the equation:
Cm = [ Pi*E0*Er*L* ln(1 + 2b/c) ] / [ln(2b/a)]^2

The task is to calculate capacitance between two parallel rectangular conductors on top of an infinite ground plane insulated with a diacritic middle layer.

The two parallel rectangular conductors both have width W, length L, and thickness T. The gap between the two is G. (Equivalently the center-to-center distance between the two is C = G + W).

The middle diacritic insulation layer has depth D and diacritic constant E which is 1 for air and larger for anything else.

Can anyone please get the derivation for calculating the capacitance between the two parallel rectangular conductors. I need detailed explanation and I want to fully understand it.

You can find it in the book
Capacitance, Inductance and Crosstalk Analysis on pages 48-65 (formulae C4-7).

Can anyone do me this favour.
Thanks in advance.

Re: mutual capacitance

You want the derivative of Cm with respect to what ???
which one is the variable or variables( partial derivative) ??

Re: mutual capacitance

eltonjohn said:

You want the derivative of Cm with respect to what ???
which one is the variable or variables( partial derivative) ??

Click to expand...

Ohhh you've mistaken me.
I dont want to find the derivative of Cm.
I just want to obtain the final equation i.e. Cm = ......
and the logic why the equation is so.
I want to arrive at the final equation for Cm .

The explanantion of the equation is given in the book that I mentioned, but I dont have the access to the book.
If you could copy and paste the solution here it would be of help to me.