What settings should I use for Longley-Rice soil conductivity and permittivity values?
The Longley-Rice model includes inputs for soil characteristics as part of the propagation parameters. The values for soil conductivity and permittivity primarily affect lower frequency calculations, where more energy is propagated in the groundwave portion of the signal. For most VHF and higher frequency applications, the soil characteristic will have minimal effect on the predicted signal strength. The values for conductivity and permittivity are entered in the Longley-Rice propagation template. You can use the templates to create a number of different parameter sets for different conditions. The Longley-Rice documentation specifies suggested values based on the general conditions, such as “Average Ground”. The values are included in the pull down list on the template for permittivity: Likewise, suggested values are provided for conductivity: If your application of TAP requires more specific information about soil characteristics in the area under study, you can use measured values,
