INPUT DATA:
The calculation is by the following equation:
Comparing the formulas, it is easy to see that the characteristic impedance of a single-wire unbalanced line is half of the characteristic impedance of a two-wire balanced one, only the distance D is replaced by 2*H. This follows from the laws of electrodynamics, since a solid conductive plane is a symmetry plane for a two-wire TL.
This calculation (as well as the calculation of many other RF TL) is implemented in our Android app "Characteristic impedance", which you can download by clicking or scanning the QR code below. The app allows you to get additional parameters of a TL.
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