This article incorporates public domain material from Federal Standard 1037C. General Services Administration. Archived from the original on 2022-01-22. (in support of MIL-STD-188).
In telecommunication, ground constants are the electrical parameters of earth: electrical conductivity, σ, electrical permittivity, ε, and magnetic permeability, μ.
The values of these parameters vary with the local chemical composition and density of the Earth. For a propagating electromagnetic wave, such as a surface wave propagating along the surface of the Earth, these parameters vary with frequency and direction.