Electromagnetic Exposure and Quality of Service in the Downlink of Wireless Cellular Networks

We study in this paper both the electromagnetic exposure and the quality of service perceived by the users in the downlink of wireless cellular networks. We calculate the cumulative electromagnetic radiation received at each location from the interfering base stations in a large (eventually infinite) hexagonal cellular network. We establish a lower bound of the cell radius above which the safety zone has not to be increased due to this cumulative effect compared to the situation when one accounts only for the power received from the serving base station. On the other hand, fixing some quality of service target, we calculate the minimal emitted power required to serve a given traffic demand density with cells of a given radius. This permits to see whether the operator may reduce the power emitted currently in some parts of his network without degrading the quality of service. This is particularly interesting in the perspective of a potential reduction of the regulatory exposure threshold. Thus the present study shows when and of how much can be reduced the exposure of the people without sacrificing the users quality of the service.