Specific capacitance of coaxial waveguide

A coaxial waveguide is an electrical cable consisting of a central conductor and a shield arranged coaxially and separated by an insulating material or an air gap. It is used to transmit radio frequency electrical signals. The specific capacitance of a coaxial waveguide depends on the radius of the outer conductor and the radius of the inner conductor, as well as on the permittivity of the insulator material.

specific_capacitance

capacitance of the waveguide per unit length.

Symbol:

C

Latex:

\(C\)

Dimension:

capacitance/length

absolute_permittivity

absolute_permittivity of the insulator.

Symbol:

epsilon

Latex:

\(\varepsilon\)

Dimension:

capacitance/length

outer_radius

radius of the outer conductor.

Symbol:

r_o

Latex:

\(r_\text{o}\)

Dimension:

length

inner_radius

radius of the inner conductor.

Symbol:

r_i

Latex:

\(r_\text{i}\)

Dimension:

length

law

C = 2 * pi * epsilon / log(r_o / r_i)

Latex:

\[C = \frac{2 \pi \varepsilon}{\log \left( \frac{r_\text{o}}{r_\text{i}} \right)}\]