The wire stripline transmission line is similar to a standard stripline transmission line, but with a round conductor. Modeling approximation can be used to understand the impedance of the wire stripline transmission line.
A wire stripline is constructed with a round conductor suspended between two ground planes. The conductor and ground planes are separated with a dielectric. This calculator assumes the distance between the two reference planes to be an equal distance.
The impedance Z0 of a transmission line consisting of a circular signal conductor having a diameter d and centered between parallel ground planes separated by a distance h is given by:
Eq. 1
Microstrip impedance shall be calculated according to above Eq. 1.