The Messier soil model describes the variation of permittivity and conductivity with frequency. σ is conductivity, εr is relative permittivity, σ0 is conductivity at low frequencies, ε∞ is permittivity at high frequencies, ε0 is the vacuum permittivity, and f is frequency. M. A. Messier derived the equations empirically in the 1980s.
I validate ground constant curves by fitting the model to them. I also use it to extrapolate ground constants to other frequencies. σ0 and ε∞ are free parameters in both applications.
This paper compares the Messier soil model with several others.
88–108 MHz