Reproducibility Studies of Instantaneous and 6-Minute Average Exposure Measurements Around 5G Massive-MIMO Base Stations

Measurements of RF exposure to mobile radio base stations are important for risk communication. We measured instantaneous exposure with a focus on 5G with an exposimeter on an identical route on three afternoons to study the reproducibility. Due to different walking speeds, the relationship between time and place was not identical for the measurements, so time is not suitable as a reference for comparison. When the distance walked was used as reference, accuracy problems of the exposimeter's internal GPS system occurred, resulting in a mismatch between the actual location and the GPS location. This problem was successfully corrected by using the gradient descent with momentum method. The three measurements show a variation in maximum measured exposure of up to 5.4 dB for a selected section of the route, which is reduced to 2.8 dB when averaged over 6-minute intervals, which is acceptable given typical measurement uncertainties of ±3 dB.