Are there any publications with a numerical modeling of human body exposure to the EM waves of the mobile base station antenna for different GSM frequencies?
One of them is using Friis transmission equation combined with Finite Difference in Time Domain (FDTD) method to carry out investigation on Specific Absorption Rate (SAR).
SAR is calculated from the electric field strength, conductivity and the mass density of the material and as the distance increases electric field strength reduces. That's why the electromagnetic fields from the base stations that people are exposed to are generally much weaker than fields created by mobile phones held to the ear when making a call.
look at the papers attached. Hope it will help you.