Measurement and analysis of RF EMF exposure to 5G mobile communication base stations with beamforming

This paper reports key findings from a large-scale research study of radio frequency electromagnetic fields (RF EMF) exposure to 5G mobile communication base stations with massive MIMO, i.e. with beamforming antennas. Exposure measurements taken at 100 measurement points, systematically selected in the coverage area of ten 5G base stations in the 3.6 GHz band, resulted in maximal exposure levels between 0.2% (0.15 V/m) and 28.9% (17.6 V/m) of the ICNIRP’s 1998 reference levels (median 4.7% resp. 2.9 V/m). The instantaneous exposure levels without forced traffic ranged between 0.04% (0.03 V/m) and 1.1% (0.67 V/m) (median 0.09% resp. 0.05 V/m); the exposure levels caused by a typical use case (TV live stream at the measurement point) were only slightly higher, between 0.04% (0.03 V/m) and 1.3% (0.8 V/m) (median 0.2% resp. 0.12 V/m). The slight increase of measured field strength caused by TV streaming corresponds to a tiny increase of the downlink exposure to a person operating the user terminal in practice compared to exposure without forced traffic. The exposure dependence on the elevation angle at which the base station is seen from the measurement point observed for LTE (4G) base stations with a fixed radiation pattern has changed for 5G massive MIMO base stations. Due to the added beam steering capability in the latter, for the 5G beamforming antennas investigated, the highest exposure levels occurred at higher elevation angles compared to 4G.