Super directive antennas for low electromagnetic field mobile communications

This paper investigates electromagnetic field (EMF) exposure in heterogeneous cellular networks, where clusters of small cells are deployed to create local hotspots inside the macro cell. In the past, most of the research has focused on mitigating inter-cell interference and reducing the network energy consumption. However, the expected dense deployment of small cells might increase the public concern on EMF, and urge novel management techniques and hardware solutions to mitigate the EMF exposure while satisfying the requirements of quality of service. Hence, we propose to integrate small cells equipped with directive antenna to reduce the required uplink power transmission at end users to limit the associated EMF exposure. We discuss the technical challenges and highlight the design options of this approach, and we present the FP7 LEXNET methodology to evaluate the daily exposure at mobile users. Finally, a preliminary performance evaluation quantifies the benefits of our solution.