Electromagnetic field strength distribution in Wi-Fi signals covered areas: An experimental analysis of the variables that influence the exposure levels

The assessment of exposure to the radiation emitted by wireless devices need to take into account the complexity of WLAN networks and the quasi-stochastic nature of Wi-Fi signals. By analyzing only the maximum possible field strength and the traffic in such networks, one cannot accurately express the human exposure level. The type of transmitted information and the transmission protocol are factors that have significant influence on the field distribution in time and in amplitude. At the same transmission rate substantial differences may occur, depending on the traffic direction. All these aspects are analyzed here in different operating scenarios of WLAN devices within a network. The results of this paper show that the real electric field levels may vary between 15% and 80% of the maximum field strength - when measurements are made in the frequency domain only.