The wire microstrip transmission line is similar to a standard microstrip transmission line, but with a
round conductor. Modeling approximation can be used to understand the impedance of the wire microstrip
transmission line.
Description
A wire microstrip is constructed with a round conductor suspended over a ground plane. The conductor and
ground plane are separated with a dielectric. As with the standard microstrip trace, an effective dielectric
constant is calculated because air is on one side of the trace where another dielectric is between the wire
and the ground plane.
Example
An example of a wire microstrip might most often be found in prototypes or reworked boards where a wire is
used over the top of pcb or copper clad material. If there is an insulator around the wire then this
calculator will be an estimate. Include both the pcb dielectric thickness as well as the wire insulation in
the height calculation.
Microstrip Transmission Line Models
Models have been created to approximate the characteristics of the wire microstrip transmission line.
Impedance calculation
Microstrip impedance shall be calculated according to Eq. 3 detailed above.
Effective Dielectric Constant calculation
Effective dielectric constant shall be calculated according to Eq. 1 or Eq. 2 detailed above, depending on
the value of the (d/h) ratio.
