Coaxial Cable Impedance

Inner Diameter, d1= m
Shield Diameter, d2= m
Rel. Permittivity, e=
Insulator

Impedance, Z0= ohm
Velocity factor, vf=

Compute impedance of a coaxial transmission line cable. Velocity factor indicates reduction of wave propagation speed compared to speed of light and is only dependent on the insulator permittivity. Often foam of insulator material is used with reduced relative permittivity and increased velocity factor.

© 2011 Tom Ahola