An issue related to conductivity is the attenuation (α) of radar signals by conductive soils and overburden. This is usually quoted in decibels per meter and in the frequency range 100 to 1000 MHz is approximated as (Annan, 1991):

(22)

where

For example, over ground having a conductivity of 30 mS/m and K of 25, a typical GPR signal would be attenuated at α = 10.1 decibels/meter. A good radar system might have 100 dB of sensitivity to use in ground transmission. In this environment, its penetration would be limited to 5 meters (of two-way travel).